Engine test benches are crucial instruments to perform tests on internal combustion engines. Since many factors affect tests results, an engine test bench is usually equipped with several conditioning systems (oil, water and air temperature, air humidity, etc.), in order to maintain the controlled variables to the target values, throughout the test duration. The conditioning systems are often independently controlled by means of dedicated programmable logic controllers (PLC), but a centralized model-based management approach could offer several advantages in terms of promptness and accuracy. This work presents the application of such control methodology to oil, water, and HVAC (heating, ventilating, and air conditioning) conditioning systems, where each actuator is managed coupling model-based open loop controls to closed loop actions. The main advantage of integrating the management of several actuators is that the control actions can be coordinated, similarly to what has been

Corti, Enrico, Taccioli, Michele, Ponti, Fabrizio

A Study Isolating the Effect of Bore-to-Stroke Ratio on Gasoline Engine Combustion Chamber Development

2016-01-217710/17/2016

A unique single cylinder engine was used to assess engine performance and combustion characteristics at three different strokes, with all other variables held constant. The engine utilized a production four-valve, pentroof cylinder head with an 86mm bore. The stock piston was used, and a variable deck height design allowed three crankshafts with strokes of 86, 98, and 115mm to be tested. The compression ratio was also held constant. The engine was run with a controlled boost-to-backpressure ratio to simulate turbocharged operation, and the valve events were optimized for each operating condition using intake and exhaust cam phasers. EGR rates were swept from zero to twenty percent under low and high speed conditions, at MBT and maximum retard ignition timings. The increased stroke engines demonstrated efficiency gains under all operating conditions, as well as measurably reduced 10-to-90 percent burn durations. The results were quite non-linear, with the majority of the gains achieved

Hoag, Kevin L., Mangold, Barrett, Alger, Terrence, Abidin, Zainal, Wray, Christopher, Walls, Mark, Chadwell, Christopher

A 24-hour battle of speed and EFFICIENCY

16AUTP06_0106/01/2016

At Le Mans this month, amped-up hybrid prototypes from Audi and Toyota face a revamped Porsche 919 while Ford hopes to recapture glory with its new GT-R. World endurance racing at Le Mans is no longer only about who finishes first after a grueling 24 hours, but also about winning with the greatest energy efficiency. For 2016, the Federation Internationale de L'Automobile (FIA) has tightened the fuel allowance for the top-echelon Le Mans Prototype 1 (LMP1) category in an attempt to further link racing and efficiency-and as an attempt to arrest the stunning increases in speed seen during 2015. This year, the fuel allowed per lap has been reduced by 10%, for an approximate reduction in energy per lap of about 10 megajoules (2.77 kW·h). Peak instantaneous fuel flow also is reduced by 10%.

Carney, Dan

Pushing the ICE forward, gradually

16AUTP06_0206/01/2016

Emergent technologies from BorgWarner, Eaton and Mahle aim for greater efficiency in gasoline and diesel engines. Free lunches don't exist in the quest to improve vehicle efficiency and reduce emissions. No one knows this better than powertrain engineers whose work is a constant series of tradeoffs that must be tackled if the auto industry is serious about reducing CO2. Do you want enhanced drive-cycle fuel economy? It could cost you real-world performance. You say your latest dyno tests indicate efficiency improvements through charge dilution? Well, what about the impact to specific power and torque and full-load pumping losses? These are the arcane kinds of tradeoffs the industry grapples with as it seeks effective, low-cost production engine solutions, noted Dr. Terry Alger, who directs spark-ignition R&D at the Southwest Research Institute (SwRI).

Brooke, Lindsay

Port Design Criteria for 2-Stroke Loop Scavenged Engines

2016-01-061004/05/2016

Interest in 2-stroke engines has been recently renewed by several prototypes, developed for the automotive and/or the aircraft field. Loop scavenging, with piston controlled ports is particularly attractive, but the configurations successfully developed in the past for motorbike racing (in particular, the 125cc unit displacement, crankcase pump engines), are not suitable for automotive applications. Therefore, new criteria are necessary to address the scavenging system design of the new generation of 2-stroke automobile/aircraft engines. The paper reviews the transfer ports optimization of a loop scavenged 2-stroke cylinder, whose main parameters were defined in a previous study. The optimization has been carried by means of a parametric grid, considering 3 parameters (2 tilt angles, and the focus distance), and 3 different engine speeds (2000-3000-4000 rpm, assuming a Diesel engine). A set of scavenging CFD-3d simulations have been performed by using a customized version of KIVA-3V

Mattarelli, Enrico, Rinaldini, Carlo Alberto, Savioli, Tommaso

Transient Gas Exchange Simulation and Uniflow Scavenging Analysis for a Unique Opposed Piston Diesel Engine

2016-01-108704/05/2016

To achieve more stringent exhaust emission regulations will face more and more daunting challenges nowadays. It needs more new technologies to improve the IC engine performance but needing higher costs in order to meet Euro 6 and EPA standards in USA. Recently the opposed-piston engine (OPE) has been treated as the promising product to meet these new regulations but relatively lower costing. Although two-stroke OPE owning inherent thermal efficiency and power density advantages, the inefficient scavenge efficiency appears to become the main obstacle to enhance combustion efficiency whilst reducing exhaust gas emission. For the improvement of scavenge efficiency the transient gas exchange simulation was carried out for multiple Cases here, including two intake port configurations at various back pressures in exhaust system and two port timings. The effects of exhausting back pressure, porting timing and intake port layout on scavenging and trapped air mass in cylinder all were

Changming, He, Sichuan, Xu

Development of a Third Generation Dynamic Intake Air Simulator for Single-Cylinder Test Engines

2015-01-088504/14/2015

This paper details the development of a new dynamic Intake Air Simulator (IAS) for use on single-cylinder test engines, where the gas dynamics are controlled to accurately simulate those on a multi-cylinder engine during transient or steady-state operation. The third generation of Intake Air Simulators (IAS3) continues a development of new technology in the Powertrain Control Research Laboratory (PCRL) that replicates the multi-cylinder engine instantaneous intake gas dynamics on the single-cylinder engine, as well as the control of other boundary conditions. This is accomplished by exactly replicating the intake runner geometry between the plenum and the engine intake valve, and dynamically controlling the instantaneous plenum pressure feeding that runner, to replicate the instantaneous multi-cylinder engine intake flow. The plenum pressure is controlled in this technology by means of six rotary valves, seven proportional valves, and the throttle valve system from the representative

Murphy, Mark B., Moskwa, John J.

A Study of a Highly Boosted and Efficient Downsized Ethanol Direct Injection (EDI) Engine in Two Different Configurations for the Purpose of Replacing High-Displacement Gasoline Engines

2015-01-125504/14/2015

The paper presents a layout of a highly boosted Ethanol Direct Injected (EDI) engine with extreme downsizing, which represents a powerful means to reduce emissions at reduced production costs. The substitution of high-displacement engines (2.4- or 3.0-liter) by a downsized turbocharged EDI-engine is studied. The paper describes the detailed layout of all engine hardware and in particular, the cylinder head structure including the optimized intake and exhaust manifolds as well as implemented DI injectors. The paper continues with a presentation of the experimental data obtained at the engine test rig. The paper concludes presenting a series of experimental data obtained with the downsized engine mounted in a car as a replacement for its original high-displacement engine.

Pontoppidan, Michael, Baeta, Jose G. C.

Demands on Future Timing drives - Chain and Belt in Competition

2015-01-127504/14/2015

When designing a new internal combustion engine, the choice of technology for the timing drive system is one of the key decisions that determines the overall characteristics of the engine with far reaching implications on the remaining architecture and overall packaging of the engine. For Passenger car engines there are two mainstream technologies: toothed belts and chains. Each of these offers several sub-variants, such as dry vs. wet belt, or toothed vs. roller chain. This paper examines the differences between these technologies in relation to the key engine attributes including package, cost, weight, durability, NVH and frictional losses. A quantitative evaluation is made where possible, based on data collected from recent engine development programs, backed up by literature study and data from the component supply industry. These differences are reviewed in the light of current and expected future engine development trends in order to give a basis for the engine designer to choose

Schoeffmann, Wolfgang Johann, Truffinet, Caroline, Howlett, Michael, Ausserhofer, Norbert, Zurk, Andreas

Cumulated Microslip in Component Assembly of Engine and Gearbox

2015-01-173704/14/2015

Today new automotive engine design is optimized in terms of mass. However, in terms of structural stiffness, optimizations mainly consider eigenfrequency criteria. But in assembly components with very low stiffness, cumulated microslip phenomena can occur when the structures are subject to cyclic loadings. In time and after a large number of cycles, macro-displacements can be observed between assembly components and then assembly failures will occur. Bush, plain bearing, roller bearing in conrod or in gearbox can be subject to this kind of problem. In this paper, after a short description of various mechanisms which can cause microreptation phenomena, two types of cumulated microslip occurring in the engine and the gearbox are presented. Behavior specificities will be highlighted to remind how unusual cumulated microslips are. Based on field data, it appears that the probability of both phenomena occurring is extremely low. This implies that it is not appropriate to use devices

Ligier, Jean-louis, Benoit, Mathieu, Damaz, Sylvain

Performance of Ancillary Systems of 2014+ Le Mans LMP1-H Vehicles and Optimization

2015-01-116304/14/2015

This study details the investigation into the hybridization of engine ancillary systems for 2014+ Le Mans LMP1-H vehicles. This was conducted in order to counteract the new strict fuel-limiting requirements governing the powertrain system employed in this type of vehicle. Dymola 1D vehicle simulation software was used to construct a rectilinear vehicle model with a map based 3.8L V8 engine and its associated ancillary systems, including oil pumps, water pump and fuel pump as well as a full kinetic energy recovery system (ERS). Appropriate validation strategy was implemented to validate the model. A validated model was used to study the difference in fuel consumption for the conventional ancillary drive off of the internal combustion engine in various situational tests and a hybrid-electric drive for driving engine ancillaries. Investigation showed that the implementation of hybrid ancillaries in the Le Mans circuit would achieve a 40cc fuel savings per lap over the conventional

Elias, Gabriel, Samuel, Stephen, Picarelli, Alessandro

A Study into Compression Ring Dynamics using Response Surface Methodology

2015-01-133504/14/2015

For decades the operational dynamics of the compression ring during operation, have been subject to debate [1, 2, 3, 4, 5, 6, 7]. A complex computer simulation, using Design Of Experiments (DOE) methodology, was developed to study the effect of the compression ring rotation during running-in stages. Response Surface (RS) has been used to optimize ring displacement, as function of ring mass, width and radius. The optimised surface response has been compared to used compression rings and has shown a 2% variation between calculated and measured values.

Dickinson, Matthew W., Renevier, Nathalie, Calderbank, John

A Naturally Aspirated Four Stroke Racing Engine with One Intake and One Exhaust Horizontal Rotary Valve per Cylinder and Central Direct Injection and Ignition by Spark or Jet

2015-01-0006

03/10/2015

The paper discusses the benefits of a four stroke engine having one intake and one exhaust rotary valve. The rotary valve has a speed of rotation half the crankshaft and defines an open passage that may permit up to extremely sharp opening or closing and very large gas exchange areas. The dual rotary valve design is applied to a racing engine naturally aspirated V-four engine of 1000cc displacement, gasoline fuelled with central direct injection and spark ignition. The engine is then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds, with reduced frictional losses, and with larger gas exchange areas while also improving the fuel conversion efficiency thanks to the sharpness of opening or closing events. The novelty in the proposed dual rotary valve system is the combustion chamber

Boretti, Alberto, Jiang, Shuheng, Scalzo, Joseph