Browse Topic: Crankshafts

Items (270)

The increasing popularity of e-bikes, especially pedelecs, has led to a growing interest in consideration of e-bike cycling. To achieve a deeper understanding on the process of e-bike cycling and in particular the effects on the rider it can be instrumental to use simulation methods. In this context, the e-bike drive system and its function are of central importance for e-bikes. Therefore, this work proposes a functional modeling of the powertrain of an e-bike with a mid-drive motor, considering legal constraints and support functionalities. The model incorporates the mechanical transmission between pedals, motor, and crank shaft, allowing for a detailed analysis of the e-bike’s performance. Additionally, the support mechanism is depicted, where an electric motor amplifies the rider’s pedaling torque. The electrical behavior of the motor, energy consumption, and battery state of charge are also integrated into the model. This comprehensive approach aims to provide a generic

Rauch, Yannick, Kettner, Maurice, Kriesten, Reiner

Optimization of HEV Vehicle’s Engine Modulated Noise

2025-01-008405/05/2023

One 1.5L Miller-cycle turbocharged four cylinder gasoline hybrid engine is installed on a certain hybrid vehicle. When accelerating at low to medium speeds with a small throttle, there is a "da da" knocking noise inside the car, which seriously affects the overall sound quality of the vehicle. By analyzing the vibration and noise data of the engine, it was found that the frequency of the abnormal knocking sound is 200-1000Hz, which presents a half order characteristic in the time domain, that is, one knocking occurs when the engine crankshaft rotates twice. Through Hilbert demodulation analysis of the vibration data in the problem frequency range, it was found that the knocking noise was modulated in the frequency domain, with a modulation frequency of half of the crankshaft rotation frequency. By building a fully flexible multi-body dynamic model of a hybrid powertrain and inputting the engine's cylinder pressure excitation, the combustion excitation is coupled with mechanical

dan, Kong

Numerical Study of an I4 Engine Oil Ejection During an Accidental Cap-off Running Condition for Two Baffle Designs

2022-01-047203/29/2022

Three-dimensional transient numerical simulations are conducted to mimic the operating conditions of a four-cylinder internal combustion engine running without its engine-oil cap on. Navier-Stokes equations are solved together with the multiphase Volume of Fluid (VOF) model and the k-ϵ turbulence model. The engine crank shaft is mechanically connected to two cam shafts through a chain, which operates below the oil-cap open boundary. A baffle is located between the chain and the oil-cap opening to minimize oil spills. The chain geometry and dynamics are captured accurately through volume remesh and conformal mapping techniques. The motion of the four pistons, crank shaft, and two cam shafts is also considered. Retaining all these mechanical and geometrical details in the simulations is essential to obtain accurate oil ejection results. The crank shaft rotates at 1200 RPM and the study is conducted for two different baffle designs. Experimental results indicate a steady-state oil

Jorda Juanos, Albert, Schlautman, Jeff, Parsons, Neal, Pandey, Ashutosh

Multi-Dimensional CFD Studies of Oil Drawdown in an I4 Engine

2022-01-047303/29/2022

A computational study based on unsteady Reynolds Averaged Navier Stokes that resolves the gas-liquid interface was performed to examine the unsteady multiphase flow in a 4 cylinder Inline (I-4) engine. In this study, the rotating motion of the crankshaft and reciprocating motion of the pistons were accounted for to accurately predict the oil distribution in various parts of the engine. Three rotational speeds of the crankshaft have been examined: 1000, 2800, and 4000 RPM. Of particular interest is to examine the mechanisms governing the process of oil drawdown from the engine head into the case. The oil distributions in other parts of the engine have also been investigated to understand the overall crankcase breathing process. Results obtained show the drawdown of oil from the head into the case to be strongly dependent on the venting strategy for the foul air going out of the engine through the PCV system. Results also show the dynamic holdup of oil in the steady operation to be

Pandey, Ashutosh, Schlautman, Jeff, Nichani, Varun

Design Challenges & Solution in Modifying Compact 4-Stroke Diesel Engine while Adapting D-Cycle Technology

2022-01-072503/29/2022

This paper reviews application of 2-Stroke D-Cycle (i.e. Differential Stroke) technology to compact tractor 4-Stroke 2.7L 4-Cylinder CRS (Common Rail System) Naturally aspirated (NA) Diesel engine for improving efficiency & power. The study considers design challenges that are presented for accommodating D-cycle technology in engine. The paper also covers resolving those challenges with established technical solutions. Study focuses on modifying conventional compact 4-stroke diesel engine with the intention of keeping design changes minimal for incorporating differential stroke technology. Designing of vertically splitting lightweight piston crown which can smoothly engaged and separated from main piston body without any impact, stem rod which connects piston crown with rocker arm, hollow connecting rod and rocker arm which is actuated by additional camshaft in addition to present camshaft. Lubrication of additional camshaft is done by extending existing oil galleries. Gear train

Telshinge, Pravin, Paulraj, Lemuel

Study of Friction Reduction Potential in Light- Duty Diesel Engines by Lightweight Crankshaft Design Coupled with Low Viscosity Oil

2020-37-000606/23/2020

Over the last two decades, engine research has been mainly focused on reducing fuel consumption in view of compliance with more stringent homologation cycles and customer expectations. As it is well known, the objective of overall engine efficiency optimization can be achieved only through the improvement of each element of the efficiency chain, of which mechanical constitutes one of the two key pillars (together with thermodynamics). In this framework, the friction reduction for each mechanical subsystem has been one of the most important topics of modern Diesel engine development. The present paper analyzes the crankshaft potential as contributor to the mechanical efficiency improvement, by investigating the synergistic impact of crankshaft design itself and oil viscosity characteristics (including new ultra-low-viscosity formulations already discussed in SAE Paper 2019-24-0056). For this purpose, a combination of theoretical and experimental tools have been used to design an

Mafrici, Salvatore

Study of the Effects of Oil Supply and Piston Skirt Profile on Lubrication Performance in Power Cylinder Systems

2019-01-236412/19/2019

In internal combustion engines, the majority of the friction loss associated with the piston takes place on the thrust side in early expansion stroke. Research has shown that the Friction Mean Effective Pressure (FMEP) of the engine can be reduced if proper modifications to the piston skirt, which is traditionally barrel-shaped, are made. In this research, an existing model was applied for the first time to study the effects of different oil supply strategies for the piston assembly. The model is capable of tracking lubricating oil with the consideration of oil film separation from full film to partial film. It is then used to analyze how the optimized piston skirt profile investigated in a previous study reduces friction. It was found that the profile is able to maintain a larger amount of lubricant between the lower part of the piston skirt and the cylinder liner during compression stroke, thereby generating more hydrodynamic pressure, instead of asperity contact pressure, to balance

Meng, Zhen, Ahling, Sebastian, Tian, Tian

Nondestructive Measurement of Residual Strain in Connecting Rods Using Neutrons

05-12-03-001810/15/2019

Abstract Increasing the strength of materials is effective in reducing weight and boosting structural part performance, but there are cases where the residual strain generated during the process of manufacturing of high-strength materials results in a decline of durability. It is therefore important to understand how the residual strain in a manufactured component changes due to processing conditions. In the case of a connecting rod, because the strain load on the connecting rod rib sections is high, it is necessary to clearly understand the distribution of strain in the ribs. However, because residual strain is generally measured by using X-ray diffractometers or strain gauges, measurements are limited to the surface layer of the parts. Neutron beams, however, have a higher penetration depth than X-rays, allowing for strain measurement in the bulk material. The research discussed within this article consists of nondestructive residual strain measurements in the interior of connecting

Ikeda, Tomohiro, Jeffery, Bunn R., Fancher, Christopher M., Motani, Ryuta, Matsuda, Hideki, Okayama, Tatsuya

Effect of Injector Cone Angle and NTP on Performance and Emissions of BS6 Engine

2019-28-010810/11/2019

The combustion phenomenon of diesel engines has got a very major impact on the performance and exhaust emission levels. Several important factors like engine components design, combustion chamber design, Exhaust gas recirculation, exhaust after treatments systems, engine operating parameters etc. decide the quality of combustion. The role of fuel injector is crucial on achieving the desired engine performance and emissions. Efficient combustion depends on the quantity of fuel injected, penetration, atomization and optimum timing of injection. The nozzle through flow, cone angle, no of sprays and nozzle tip penetration are the factors which lead to the selection of perfect injector for a given engine. This paper focusses on the selection of the best fit injector suiting the BS6 application on evaluating the performance and emission characteristics. Injectors used were with varying cone angles and NTP. The nozzle tip protrusion of the injectors were varied by changing the sealing washer

Muthusamy, Anbarasu, Shangar Ramani, Vagesh, Sinha, Pranav Kumar

Numbering System for Single Diameter Drills

J2122_201910 (Current)10/09/2019

This SAE Recommended Practice provides a systematic method for the identification of single diameter drills. It is intended to assist in the cataloging and supplying of these tools. NOTE 1— Caution must be taken when assigning codes for designators to prevent specifying drills that cannot be physically or economically manufactured. NOTE 2— In particular without limitation, SAE disclaims all responsibility for the accuracy or completeness of information contained within this report if the standards of this report are retrieved, combined, or used in connection with any software.

Motor Vehicle Council

Ford ‘cranks’ it up with another big V8 for Mustang

19AUTP09_1109/01/2019

When Ford introduced the Mustang Shelby GT350 in 2015, it was the pinnacle of Mustang-ness thanks to its 5.2-L DOHC “Voodoo” V8 that featured a flat-plane crankshaft design to enable sky-high revs (the GT350's 8200-rpm redline is one reason Ferrari has long specified flat-plane V8s) and a rollicking 526 hp at 7,500. Then there's the exotic “rip” exhaust note unique to flat-plane V8s. But contemporary musclecar development times seemingly are as quick as their ever-dropping 0-to-60 mph runs-and before Ford released the Shelby GT350, its SAE-certified 526 hp already had been eclipsed by the 707-hp supercharged 6.2-L Hemi V8 in the Dodge Challenger SRT Hellcat and later the 797-hp Hellcat Redeye. Prior to all this, GM's Chevrolet started the hyper-power frenzy by generating 650 hp from the supercharged 6.2-L OHV V8 launched for the 2012 Camaro ZL1.

Visnic, Bill

Evaluation and Selection of Turbocharger Meeting BS6 Emission Norms for 1.99l Engine

2019-26-005801/09/2019

Migration to BS6 emission norms from BS4 levels involves strenuous efforts involving advanced technology and higher cost. The challenging part is on achieving the stringent emission norms without compromising the engine fuel economy, performance and NVH factors. Selection of hardware and attaining an optimal behaviour is therefore vital. This article focuses on the evaluation of three different configuration of turbochargers for the same engine to meet the BS6 emission norms and performance. The turbocharger samples used measure the same compressor diameter with varying trim ratios. Simulation and testing of turbochargers ensured positive results for confirmation of the system. Parameters like low speed torque, smoke and compressor efficiency were evaluated and analysed for all configurations. The safe limits of surge and choke regions of all the compressors were also studied and verified. Influence of varying compressor trim on the performance and emissions were examined thoroughly in

J, Giftson, Muthusamy, Anbarasu, Shangar Ramani, Vagesh, Bhachchu, Gurtej, R, Sivasubramamanian, Anand, M, K, Arun

Limitations of Two-Stage Turbocharging at High Flight Altitudes

03-11-05-003409/17/2018

High-altitude long-endurance (HALE) unmanned aerial vehicles (UAVs) are used for high flight altitudes, which enable low drag and fast flight with minimal fuel consumption. Two-stage turbocharging is necessary to sustain sea-level power at high flight altitudes. In this study, the limitations of two-stage turbocharging at high flight altitudes typical for HALE UAVs are analyzed for the first time. The obtained results show that the minimum available engine power increases as the altitude rises. This will limit the ability of the aircraft to descend rapidly. Furthermore, at high altitudes, if a lower operating point is required for a fast descent, further recovery to full power for climbing or cruising could be unavailable. In the latter cases, a lower altitude must be reached before full power would be available again. A basic algorithm for the assessment and analysis of the limitations of UAV engines with two-stage turbochargers operating at high altitudes is suggested.

Fass, Yehuda, Tartakovsky, Leonid

DRIVE – TYPE XV ENGINE ACCESSORY - DESIGN STANDARD FOR

AS20005A (Current)07/16/2018

E-25 General Standards for Aerospace and Propulsion Systems

Comparative Studies of Different VGT Designs on Performance and Smoke of CRDe Engine

2018-28-007407/09/2018

Diesel engines have occupied a significant position in passenger car applications in the present automotive sector. Turbochargers find a very prominent role in diesel engines of all applications in order to achieve desired power and better fuel economy. Gaining higher torque at lower engine speeds with low smoke levels is a very tough task with fixed geometry turbochargers due to availability of lower air mass resulting in higher smoke emissions. Variable geometry turbochargers are capable of providing better torque at lower speeds and reduced smoke emissions on Common Rail Diesel engines. The Variable Geometry Turbocharger types used in this study are straight profile nozzle vanes (sample A) and curved profile nozzle vanes (sample B). The curved profile vanes as seen in sample B results in reduced variation of circumferential pressure distortions. Curved blade profile vane sample results in better low speed torque along with reduced fuel consumption and smoke emissions when compared

Shangar Ramani, Vagesh, Muthusamy, Anbarasu, Bahl, Sachin, Ramanathan, Hariharan, Halbe, Vasudeo Ganesh

PROPELLER SHAFT END, FLANGED TYPE - NO. 1, 2, 3, 4, 5, & 6

AS127E (Current)05/07/2018

E-25 General Standards for Aerospace and Propulsion Systems

Influence of Miller Cycles on Engine Air Flow

03-11-02-001104/18/2018

The influence of the intake valve lift of two Miller cycles on the in-cylinder flow field inside a DISI engine is studied experimentally since changes of the engine flow field directly affect the turbulent mixing and the combustion process. For the analysis of the impact of the valve timing on the general flow field topology and on the large-scale flow structures, high-speed stereo-scopic particle-image velocimetry measurements are conducted in the tumble plane and the cross-tumble plane. The direct comparison to a standard Otto intake valve lift curve reveals evidently different impacts on the flow field for both Miller cam shafts. A Miller cycle that features late intake valve closing shows a flow field comparable to the standard Otto valve timing and a tumble vortex of strong intensity can be identified. Hence, turbulent mixing is as sufficient as for the standard Otto valve timing, although the Miller cycle intake valve timing leads to a pressure reduction of approximately 20%. In

Braun, Marco, Klaas, Michael, Schröder, Wolfgang

Integrated Exhaust Rocker Arm Lost Motion Compression Release Engine Brake with Novel Reset Mechanism for Heavy Duty Diesel Engines

2018-01-038104/03/2018

A new compression release engine brake system has been developed which utilizes the well-known lost motion idea along with an entirely new valve resetting mechanism. The engine brake is fully integrated into the exhaust rocker arm, making it highly compact. The novel reset mechanism provides a pressure sensing reset timing which optimizes engine brake performance and valve train stress at all engine speeds. Hydraulic system simulation studies were performed to first verify the concept on paper. Once acceptable performance was predicted, physical prototypes were produced. The Cummins ISL 8.9 L engine was chosen as a proof of concept platform due to its availability and its factory engine brake option. The factory engine brake gives a data set for comparison while validating this new technology. All targets for engine brake function were achieved, and a substantial increase in performance was demonstrated.

Batcheller, Devin, Taylor, Kody

Resonance Charging Applied to a Turbo Charged Gasoline Engine for Transient Behavior Enhancement at Low Engine Speed

2017-24-014609/04/2017

Upcoming regulations and new technologies are challenging the internal combustion engine and increasing the pressure on car manufacturers to further reduce powertrain emissions. Indeed, RDE pushes engineering to keep low emissions not only at the bottom left of the engine map, but in the complete range of load and engine speeds. This means for gasoline engines that the strategy used to increase the low end torque and power by moving out of lambda one conditions is no longer sustainable. For instance scavenging, which helps to increase the enthalpy of the turbine at low engine speed cannot be applied and thus leads to a reduction in low-end torque. Similarly, enrichment to keep the exhaust temperature sustainable in the exhaust tract components cannot be applied any more. The proposed study aims to provide a solution to keep the low end torque while maintaining lambda at 1. The tuning of the air intake system helps to improve the volumetric efficiency using resonance charging effects

Raimbault, Vincent, Migaud, Jerome, Chalet, David, Bargende, Michael, Revol, Emmanuel, Montaigne, Quentin

Effect of Improvements on Crankshaft Pin Grinding and Superfinishing Processes

2017-01-032103/28/2017

This case study describes improvements to the pin grinding and superfinishing processes for a 900-mm long, 60-kg forged crankshaft used in a six-cylinder diesel engine. Machining vibrations caused by the eccentricity of the mass of the pins in relation to the journals increase the difficulty of achieving a stable and capable process. Through analysis of the crankshaft and connecting rod assembly, an opportunity is identified to improve the pin profile along its 30-mm length. Based on measurements, it is found that, owing to variations of the order of 5 μm, the pin profile (nominally flat) may vary between a concave and a convex shape. Process improvements are focused on the grinding profile. The amplitude of the grinding profile is established between 0 and 5 μm, tending toward a convex shape. The practical implementation of the proposed improvements involves the imposition of a greater restriction on the extent of the grinding profile to 3.5 μm. The improvements are based on changes

Bastos, Silvio César

Critique of Torsional Vibration Damper (TVD) Design for Powertrain NVH

2017-26-021701/10/2017

Crank train torsional vibration is an important aspect for design and development of Powertrain for NVH refinement and durability. Crank train torsional vibration parameters like angular acceleration of flywheel or twist, depends upon various design parameters like geometry of crankshaft, mass of flywheel, stiffness of clutch, mass of pulley etc. It also depends upon engine operating conditions like engine speed, engine load, combustion peak pressure and combustion pressure variation etc. Most of these parameters are decided by engine power, torque, engine architecture and packaging constraints. Addition of torsional vibration damper (TVD), which works on the principle of tuned dynamic absorber, is commonly deployed design solution to control the torsional vibrations as well as stresses (to improve durability of crank train) induced in crank train assembly at specified modal frequency. This paper is critique study, which emphasizes on importance of accurate tuning of TVD frequency to

Yadav, Arvind Kumar, Birari, Mayur, Bijwe, Vilas, Billade, Dayanand

Mechanisms for Achieving Non-Sinusoidal Waveforms on Stirling Engines

TBMG-2614901/01/2017

The current state-of-the-art Stirling engines use sinusoidal piston and displacer motion to drive the thermodynamic cycle and produce power. Research performed at NASA Glenn has shown that non-sinusoidal waveforms have the potential to increase Stirling engine power density, and could possibly be used to tailor engine performance to the needs of a specific application. However, the state-of-the-art Stirling engine design uses gas springs or planar springs that are very nearly linear, resulting in a system that resonates at a single frequency. This means that imposing non-sinusoidal waveforms, consisting of multiple frequencies, requires large forces from the drive mechanism (either the alternator or the crank shaft). These large forces increase losses, and increase the size and requirements of the control system. This innovation aims to reduce the external forcing requirements by introducing internal mechanical components that provide the forces necessary to achieve the desired

In-Situ Measurement and Numerical Solution of Main Journal Bearing Lubrication in Actual Engine Environment

2016-01-089404/05/2016

A simple method is frequently used to calculate a reciprocating engine’s bearing load from the measured cylinder pressure. However, it has become apparent that engine downsizing and weight reduction cannot be achieved easily if an engine is designed based on the simple method. Because of this, an actual load on a bearing was measured, and the measured load values were compared with a bearing load distribution calculated from cylinder pressure. As a result, it was found that some of actual loads were about half of the calculated ones at certain crank angles. The connecting rod’s elastic deformation was focused on as a factor behind such differences, and the rod’s deformation due to the engine’s explosion load was studied. As a result, it was found that the rod part of the engine’s connecting rod was bent by 0.2 mm and became doglegged. Additional investigation regarding these findings would allow further engine downsizing. In this paper, the authors mainly report that an actual load on

Matsumoto, Kenji, Harada, Hironori, Ono, Yuki, Mihara, Yuji

New Approaches for Reducing Crankshaft Vibrations in a Lightweight and Fuel-Efficient Engine

2016-01-105704/05/2016

To achieve lightweight, low friction and fuel efficient engine, the crankshaft is required to be designed lightweight, small-diameter shaft, long stroke. In this case, vibration of the crankshaft is increased by reduction of shaft stiffness. The conventional way of dealing with this increased vibration used to be to add an inertia mass ring or a double mass damper. Such an approach, however, increases weight, making the balance of weight reduction and vibration reduction less readily achieved. This paper therefore reports on how the main factors causing crankshaft vibration to increase in the shaft with reduced stiffness were clarified. Based on that clarification, efforts were made to reduce crankshaft vibration without increasing the weight of the crankshaft system. Measurement and analysis were used to analyze crankshaft vibration during operation. This showed that the main factors in the increase of vibration in a crankshaft with reduced stiffness are the coupled modes of

Miyazawa, Masaya, Mochizuki, Kei, Takashi, Kondo

Directional Mahalanobis Distance and Parameter Sensitivities

2016-01-028904/05/2016

Mahalanobis Distance (MD) is gaining momentum in many fields where classification, statistical pattern recognition, and forecasting are primary focus. It is a multivariate method and considers correlation relationships among parameters for computing generalized distance measure to separate groups or populations. MD is a useful statistic in multivariate analysis to test that an observed random sample is from a multivariate normal distribution. This capability alone enables engineers to determine if an observed sample is an outlier (defect) that falls outside the constructed (good) multivariate normal distribution. In Mahalanobis-Taguchi System (MTS), MD is suitably scaled and used as a measure of severity in abnormality assessment. It is obvious that computed MD depends on values of parameters observed on a random sample. All parameters may not equally impact MD. MD could be highly sensitive with respect to some parameters and less sensitive to some other parameters. Knowledge of

Chinta, Balakrishna

Development of a High Speed Laser Induced Fluorescence (HSLIF) System in a Single Cylinder Engine for Oil Transport Studies

2016-01-064204/05/2016

Understanding oil transport mechanisms is critical to developing better tools for oil consumption and piston skirt lubrication [1]. Our existing Two-Dimensional Laser Induced Fluorescence (2DLIF) system with an acquisition rate of 1 frame every one or two cycles was proven to be effective to display oil accumulation patterns and their evolution over many cycles in the piston ring pack system [2,3,4]. Yet, the existing system is unable to resolve instantaneous oil flow patterns in the piston-liner interface. In this work, a high-speed LIF system was developed. After a number of iterations the finalized high speed LIF system includes a 23 W, 100 kHz, 532 nm laser and a high speed camera capable of 100,000 FPS at 384 × 264 pixel resolution. After each component was selected, optimization of the quality of images taken from the system began. Each component in the optical system was tested for improvement of image quality; such components include: camera lens, beam expander, beam splitter

Zanghi, Eric, Tian, Tian

Fugine as Single-Point Compression Engine based on Supermulti-Jets Colliding with Pulse: Combustion Test of Second Prototype Engine with Strongly-Asymmetric Double-Piston System

2015-01-196409/01/2015

We proposed a new compressive combustion principle for an inexpensive and relatively quiet engine reactor that has the potential to achieve incredible thermal efficiency. The high efficiency can be achieved with colliding supermulti-jets that create complete air insulation to encase burned gas around the chamber center. We developed a small prototype engine system for gasoline, which has a strongly-asymmetric double piston and the supermulti-jets colliding with pulse. In this report, we will show combustion experimental results at startup and at steady state operation. We obtained exhaust temperature over 100 degree Celsius and pressure data, which imply auto-ignition occurrence of gasoline.

Naitoh, Ken, Shirai, Tomoya, Tanaka, Masato, Nojima, Yoshiyuki, Hashimoto, Taiki, Hasegawa, Kenya, Kojima, Kentaro, Kihara, Takahiro

An Approach for Prediction of Motorcycle Engine Noise under Combustion Load

2015-01-224406/15/2015

In this paper the approach to predict engine noise under combustion forces is presented. This Methodology is divided into three stages: 1. Multi body dynamic (MBD) Simulation to determine excitation forces 2. Vibration analysis of engine under combustion load 3. Acoustic analysis of engine to predict Sound Pressure Level (SPL). Important parts of motorcycle engine with single cylinder are considered as flexible bodies for MBD simulation. It is necessary to accurately model crankshaft ball bearing for capturing the accurate transmissibility of combustion forces from crankshaft to casings. In this work crankshaft ball bearing is modeled with 6×6 stiffness matrix. It provides coupling between radial, axial and tilting deflections of bearing and it also allows moment transfer from crankshaft to casing. It helps to predict the realistic forces at bearings. Forces predicted from MBD simulation are applied to engine FE model for carrying out vibration analysis. Predicted vibration response of

Mohite, Ulhas, Bhatia, Niket, Bhavsar, Prashant

Diesel Combustion Noise Reduction by Controlling Piston Vibration

2015-01-166704/14/2015

It has been required recently that diesel engines for passenger cars meet various requirements, such as low noise, low fuel consumption, low emissions and high power. The key to improve the noise is to reduce a combustion noise known as “Diesel knock noise”. Conventional approaches to reduce the diesel knock are decreasing combustion excitation force due to pilot/pre fuel injection, adding ribs to engine blocks or improving noise transfer characteristics by using insulation covers. However, these approaches have negative effects, such as deterioration in fuel economy and increase in cost/weight. Therefore, modification of engine structures is required to reduce it. We analyzed noise transfer paths from a piston, a connecting rod, a crank shaft to an engine block and vibration behavior during engine operation experimentally, and identified that piston resonance was a noise source. In order to absorb resonant energies caused by vertical movement of the piston, we have designed new piston

Kanda, Yasunori, Mori, Tsunehiro

Scuffing Test Rig for Piston Wrist Pin and Pin Bore

2015-01-068004/14/2015

In practice, the piston wrist pin is either fixed to the connecting rod or floats between the connecting rod and the piston. The tribological behavior of fixed wrist pins have been studied by several researchers, however there have been few studies done on the floating wrist pin. A new bench rig has been designed and constructed to investigate the tribological behavior between floating pins and pin bore bearings. The experiments were run using both fixed pins and floating pins under the same working conditions. It was found that for fixed pins there was severe damage on the pin bore in a very short time (5 minutes) and material transfer occurs between the wrist pin and pin bore; however, for the floating pin, even after a long testing time (60 minutes) there was minimal surface damage on either the pin bore or wrist pin.

Zhang, Rong, Zou, Qian, Barber, Gary, Zhou, Ben, Wang, Yucong

Improvement of the Startability with Reverse Stroke Intake Devices for a Motorcycle Engine

2014-32-010711/11/2014

This paper proposes a novel engine starter system composed of a small-power electric motor and a simple mechanical valve train. The system makes it possible to design more efficient starters than conventional systems, and it is especially effective to restart engines equipped with idling stop systems. Recently, several idling stop systems, having intelligent start-up functions and highly-efficient generate capabilities have been proposed for motorcycles. One of challenges of the idling stop systems is the downsizing of electric motors for starting-up. However, there are many limitations to downsize the electric motors in the conventional idling stop systems, since the systems utilize the forward-rotational torque of the electric motors to compress the air-fuel mixture gas in the cylinders. Our studies exceeded the limitations of downsizing the electric motors by mainly using the engine combustion energy instead of the electric energy to go over the first compression top dead center

Masuda, Takahiro, Sakai, Kouji, Yamaguchi, Yuki, Kaku, Jun-ichi, Nagasaka, Hirobumi

Two Small Prototype Engines Developed based on Pulsed Supermulti-Jets Colliding: Having a Potential of Thermal Efficiency Over 60% with Satisfactory Strength of Structure

2014-32-009911/11/2014

In our previous reports based on computations and fluid dynamic theory, we proposed a new compressive combustion principle for an inexpensive and relatively quiet engine reactor that has the potential to achieve thermal efficiency over 50% even for small combustion chambers having less than 100 cc. This can be achieved with colliding supermulti-jets that create complete air insulation to encase burned gas around the chamber center. We originally developed two small prototype engine systems for gasoline. First one with one rotary valve for pulsating intake flow and sixteen nozzles of jets colliding has no pistons. Next, we developed the second one having a strongly-asymmetric double piston system with the supermulti-jets colliding, although there are no poppet valves. The second prototype engine can vary point-compression strength due to the supermulti-jets and homogeneous compression level due to piston, by changing phase and size of two gears. A motoring test done for evaluating the

Naitoh, Ken, Ikoma, Daiki, Sagara, Hiroki, Tamura, Taro, Hashimoto, Taiki, Nojima, Yoshiyuki, Tanaka, Masato, Kojima, Kentaro, Hasegawa, Kenya, Nakai, Takuya, Nonaka, Shouhei, Kubota, Tomoaki

Measurement and Validation of Two Wheeled Vehicle Single Cylinder Engine Unbalance Force Calculation on the Crankshaft

2014-32-006111/11/2014

Ride comfort, driving stability and drivability are vital factors in terms of vehicle performance and customer satisfaction. Crankshaft unbalance is a source for the vibration that reduces the vehicle performance and it needs to be controlled to some extent such that the vehicle performance will be improved. The IC engine is made up of reciprocating and rotating parts. They produce unbalance forces during their operation and produces vibration in Vehicle. The vibration reduction will be possible by minimizing these unbalance forces and by optimizing the crankshaft of the two wheeled vehicle engine design. Many researches were made to find the causes for the vibration and to reduce it. But still there is a research gap on the testing and simulation of engine components (crankshaft, connecting rod and piston assembly). In this study, an attempt is made to represent the engine vibrations and its isolation to provide a gate way for the future work on it. This study shows the various steps

Subbu, Rama, Anthony Samy, Baskar, Sharma, Piyush Mani, Mahendiran, Prasanna

Design Guidelines of the Single-Point Auto-Ignition Engine based on Supermulti-Jets Colliding for High Thermal Efficiency and Low Noise: Obtained by Computational Experiments for a Small Strongly-Asymmetric Double-Piston Engine

2014-32-010011/11/2014

An inexpensive, lightweight, and relatively quiet engine reactor that has the potential to achieve thermal efficiency over 50% for small engines was proposed in our previous reports, which is achieved with colliding supermulti-jets that create air insulation to encase burned gas around the chamber center, avoiding contact with the chamber walls and piston surfaces. The colliding of pulse jets can maintain high pressure ratio for various air-fuel ratios, whereas traditional homogeneous compression engines due to piston cannot get high pressure ratio at stoichiometric condition. Emphasis is also placed on the fact that higher compression in this engine results in less combustion noise because of encasing effect. Here, a small prototype engine having supermulti-jets colliding with pulse and strongly-asymmetric double-piston system is examined by using computational experiments. Pulse can be generated by the double piston system of a short stroke of about 40mm. Computations at some loads

Naitoh, Ken, Okamoto, Takuma, Kubota, Tomoaki, Yamagishi, Kan, Nojima, Yoshiyuki, Tamura, Taro

Development Of Fugine Based on Supermulti-Jets Colliding with Pulse: Leading to Stable Plug-Less Start and Improvement of HCCI with Satisfactory Strength of Structure

2014-01-263910/13/2014

In our previous reports based on computational experiments and fluid dynamic theory, we proposed a new compressive combustion principle for an inexpensive, lightweight, and relatively quiet engine reactor that has the potential to achieve incredible thermal efficiency over 60% even for small combustion chambers having less than 100 cc. This level of efficiency can be achieved with colliding supermulti-jets that create complete air insulation to encase burned gas around the chamber center, thereby avoiding contact with the chamber walls, including the piston. We originally developed an actual prototype engine system for gasoline. The engine has a strongly-asymmetric double piston and the supermulti-jets colliding with pulse, although there are no poppet valves. The number of jets pulsed for intake and exhaust is eight, while both of bore and stroke are about 40mm. The present prototype engine can widely vary point-compression strength due to the supermulti-jets and mechanical

Naitoh, Ken, Hasegawa, Kenya, Kubota, Tomoaki, Hashimoto, Taiki, Nojima, Yoshiyuki, Tanaka, Masato, Kojima, Kentaro

Physical Theory of the Single-Point Auto-Ignition Engine Based on Supermulti-Jets Colliding with Pulse: Leading to Thermal Efficiency over 60% at Various Engine Speeds and Loads of Automobiles

2014-01-264010/13/2014

This paper proposes a new compressive combustion principle for an inexpensive, lightweight, and relatively quiet engine reactor that has the potential to achieve incredible thermal efficiency over 60% even for small engines having strokes shorter than 100mm, whereas eco-friendly gasoline engines for today's automobiles use less than 35% of the supplied energy for work on average. This level of efficiency can be achieved with colliding supermulti-jets that create air insulation to encase burned gas around the chamber center, thereby avoiding contact with the chamber walls, including the piston. Emphasis is also placed on the fact that higher compression results in less combustion noise because of the encasing effect. We will first show that numerical computations done for two jets colliding in line quantitatively agree with shock-tube experiment and theoretical value based on compressible fluid mechanics. Next, computations for colliding of many pulse jets distributed with point

Naitoh, Ken, Kojima, Kentaro, Okamoto, Takuma, Yamagishi, Kan, Tamura, Taro, Ishida, Kouichi, Nonaka, Shouhei

Unsteady Three-Dimensional Computational Experiments of the Single-Point Auto-Ignition Engine Based on Semispherical Supermulti-Jets Colliding with Pulse for Automobiles

2014-01-264110/13/2014

Supercomputer simulations substantiate a high potential of the new compressive combustion principle based on supermulti-jets colliding with pulse, which was previously proposed by us and can maintain high compression ratio for various air-fuel ratios. An original governing equation extended from the stochastic Navier-Stokes equation lying between the Boltzmann and Langevin equations is proposed and the numerical methodology based on the multi-level formulation proposed previously by us is included. For capturing instability phenomena, this approach is better than direct numerical simulation (DNS) and large eddy simulation (LES). A simple two-step chemical reaction model modified for gasoline is used. A small engine having a semispherical distribution of seventeen jets pulsed is examined here. Pulse can be generated by a rotary plate valve, while a piston of a short stroke of about 65mm is also included. Computations from 2,000 rpm to 20,000rpm at some loads for the present engine

Naitoh, Ken, Yamagishi, Kan, Nonaka, Shouhei, Okamoto, Takuma, Tanaka, Yoshiaki

Effect of Swirl/Tumble (Tilt) Angle on Flow Homogeneity, Turbulence and Mixing Properties

2014-01-257910/13/2014

In this work, the effect of swirl to tumble ratio on homogeneity, turbulence and mixing in a generic heavy duty Diesel engine during compression, is investigated using Large-Eddy Simulations. The main conclusion is that the relative importance of dilatation (relative volume change) increases whereas the effect of tumble breakdown decreases with the swirl to tumble ratio. In detail, we show that an increase in tumble raises the peak turbulence level and shifts the peak to earlier crank angles, which in turn leads to higher dissipation. Moreover, maximum turbulence level at top dead center is obtained for a combination of swirl and tumble rather than for pure tumble. Furthermore, it is observed that the peak turbulent kinetic energy displays levels three times greater than the initial kinetic energy of the tumble motion. Thus, energy is added to the flow (turbulence) by the piston through generation of vorticity by vorticity-dilatation interaction. Also, the intermediate swirl/tumble

Söder, Martin, Prahl Wittberg, Lisa, Lindgren, Bjorn, Fuchs, Laszlo

Application of Vacuum Assisted Carbide Dispersion Carbonitriding to Connecting Rods

2013-32-908210/15/2013

In four-cycle single-cylinder motorcycle engines, high Hertzian stress is generated on and beneath the big-end surface of the connecting rod. If the surface strength would be improved, the diameter of the big-end could be made smaller, making the entire engine smaller and lighter. Therefore, application of carbide dispersion carbonitriding using a vacuum furnace (hereinafter referred to as “vacuum CD carbonitriding”) on the big-end surface was investigated. Vacuum CD carbonitriding was carried out by three processes. The first was a CD carburizing process. This process is done to obtain granular cementite, but in order to avoid decreasing the strength, it is necessary to prevent the formation of coarsened cementite at the grain boundary. The second process was a refining process. This process is done for the purpose of refining the prior austenite grain size. The third process was a carbonitriding process. This process is done for the purpose of increasing hardness in the vicinity of

Kubota, Tsuyoshi

Study of the Motion of Floating Piston Pin against Pin Bore

2013-01-121504/08/2013

One of the major problems that the automotive industry faces is reducing friction to increase efficiency. Researchers have shown that 30% of the fuel energy was consumed to overcome the friction forces between the moving parts of any automobile, Holmberg et al. [1]. The interface of the piston pin and pin bore is one of the areas that generate high friction under severe working conditions of high temperature and lack of lubrication. In this research, experimental investigation and theoretical simulation have been carried out to analyze the motion of the floating pin against pin bore. In the experimental study, the focus was on analyzing the floating pin motion by using a bench test rig to simulate the floating pin motion in an internal combustion engine. A motion data acquisition system was developed to capture and record the pin motion. Thousands of images were recorded and later analyzed by a code written by MATLAB. In the simulation, friction and lubrication analysis for

Abed, Ghassan, Zou, Qian, Barber, Gary, Zhou, Ben, Wang, Yucong, Liu, Yuchuan, Shi, Fanghui

DRIVE - TYPE XV ENGINE ACCESSORY - DESIGN STANDARD FOR

AS20005 (Historical)

11/01/2012

E-25 General Standards for Aerospace and Propulsion Systems

PROPELLER SHAFT END, FLANGED TYPE - NO. 1, 2, 3, 4, 5, & 6

AS127D (Historical)

11/01/2012

E-25 General Standards for Aerospace and Propulsion Systems

3D CFD Analysis of the Influence of Some Geometrical Engine Parameters on Small PFI Engine Performances - The Effects on Tumble Motion and Mean Turbulent Intensity Distribution

2012-32-009610/23/2012

In scooter/motorbike engines coherent and stable tumble motion generation is still considered an effective mean in order to both reduce engine emissions and promote higher levels of combustion efficiency. The scientific research also assessed that squish motion is an effective mean for speeding up the combustion in a combustion process already fast. In a previous technical paper the authors demonstrated that for an engine having a high C/D ratio the squish motion is not only not necessary but also detrimental for the stability of the tumble motion itself, because there is a strong interaction between these two motions with the consequent formation of secondary vortices, which in turn penalizes the tumble breakdown and the turbulent kinetic energy production. The present paper starts with the development of a theoretical model which will be applied to different engine classes demonstrating how the relative importance of the tumble and squish varies changing the typical design parameters

Falfari, Stefania, Bianchi, Gian Marco, Nuti, Luca

Perkins

12OFHD0503_0105/03/2012

Insights into sustainability: Environmental, economic, and/or societal goals for a successful, and long-lasting, off-highway industry. - Sustainability matters The environmentalist Jonathon Porritt usefully defined sustainability as, “The capacity for continuance into the long-term future.” On that basis all businesses need to consider the question of sustainability since if there's no future, there's no business. Sustainability can take many guises apart from the obvious environmental one. There are also the economic and cultural facets to take into account.

Basely, Nigel

The Study of Friction between Piston Ring and Different Cylinder Liners using Floating Liner Engine - Part 1

2012-01-133404/16/2012

The objective of this work was to develop an experimental system to support development and validation of a model for the lubrication of two-piece Twin-Land-Oil-Control-Rings (hereafter mentioned as TLOCR). To do so, a floating liner engine was modified by opening the head and crankcase. Additionally, only TLOCR was installed together with a piston that has 100 micron cold clearance to minimize the contribution of the skirt to total friction. Friction traces, FMEP trend, and repeatability have been examined to guarantee the reliability of the experiment results. Then, engine speed, liner temperature, ring tension, and land widths were changed in a wide range to ensure all three lubrication regimes were covered in the experiments. It was found that for each different ring land design, the measured instantaneous friction coefficient under different engine speed, liner temperature, and ring tension can roughly collapse to the same Stribeck curve, which indicates that the modified system

Liao, Kai, Chen, Haijie, Tian, Tian

Recycling of Used Up Crankshaft Grinding Wheels

2012-01-106004/16/2012

For sustainability in automobile manufacturing, recycle, reuse, and repair of used up cutting tools is now an established process. Although many types of tools were designed for one time use and then throw, an increasing awareness of the impact on the natural resources have made manufacturers to put some of these back to use or sell it back to suppliers who have put up a mechanism to extract the elements e.g. Tungsten and use it for manufacturing of new tools. There are many ways in which cutting tools can be recycled. Be it by reshaping a used up throwaway type tool [1], by redesigning of a tool holder for the use of unused cutting edges [2] or reusing short length drills that are used in making of long oil holes in crank case, cylinder head, cam shaft or connecting rods [3]. This paper demonstrates successful use of used up crankshaft grinding wheels. These used up grinding wheels can be reformed and used for grinding of many other automobile parts that require a new grinding wheel

Datar, Surendra

An Efficient Multi-Body Approach Modeling Elastohydrodynamic Friction in Drive Systems

2012-01-091704/16/2012

Chain drives are used in powertrains for the kinematic coupling of the cam shaft, the ancillary units and the balancing shafts with the crank shaft. Advantages of chain drives are their high load carrying capacity along with increased durability whilst simultaneously being maintenance-free. A crucial issue in the drive is the optimization in regard of friction, further improving efficiency, reducing exhaust emission and abrasive wear. Modeling friction in drive systems requires precise description of the whole system dynamics. High-frequency oscillations occurring in the chain strands cause numerical problems in the friction computation. As a remedy, regularized friction curves are often used, being however not able to correctly determine all friction configurations and requiring a tradeoff between accuracy and computational efficiency. Another challenge is the sensitivity of the coefficient of friction to many factors among which are kinematic and kinetic quantities, lubricant

Filippi, Markus, Ulbrich, Heinz

The Use of Dynamic Simulation of Flow in the Design of Intake Manifolds

2011-36-008310/04/2011

In general, the design of intake manifold (IM) for Otto cycle engines starts with one-dimensional (1D) gas dynamics simulation which is used to define its main characteristics. The use of unsteady CFD (Computer Flow Dynamics) methodology can provide additional information not captured in 1D method, allowing a greater optimization of the IM geometry. Due to dynamic boundary conditions involved, this type of analysis increases significantly the results making the compilation more difficult and time consuming (1). This paper presents a methodology for unsteady simulation where qualitative results may provide a direction at an early stage in the design process. Examples and practical results already implemented are discussed to guide designers through IM development.

de Campos, Rui B., Simões, Thiago A.

LES Calculations of a Four Cylinder Engine

2011-01-083204/12/2011

A full 3D Large Eddy Simulation (LES) of a four-stroke, four-cylinder engine, performed with the AVBP-LES code, is presented in this paper. The drive for substantial CO₂ reductions in gasoline engines in the light of the global energy crisis and environmental awareness has increased research into gasoline engines and increased fuel efficiencies. Precise prediction of aerodynamics, mixing, combustion and pollutant formation are required so that CFD may actively contribute to the improvement/optimization of combustion chamber, intake/exhaust ducts and manifold shapes and volumes which all contribute to the global performance and efficiency of an engine. One way to improve engine efficiency is to reduce the cycle-to-cycle variability, through an improved understanding of their sources and effects. The conventional RANS approach does not allow addressing non-cyclic phenomena as it aims to compute the average cycle. LES on the other hand is particularly well suited to study unsteady flow

Laget, Olivier, Reveille, Benjamin, Martinez, Lionel, Truffin, Karine, Habchi, Chawki, Angelberger, Christian

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