Browse Topic: Heat exchangers

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A fluid-structure- interaction based methodology to evaluate aero-thermal performance of deformable air guides2026-26-0364To be published on 01/16/2026
An air guide in a car directs fresh air onto the Heat Exchangers (HXs) to facilitate efficient thermal management. It is of paramount importance that the air guide creates a proper sealing and prevents any leakage of the incoming fresh air. It is achieved in two ways – 1) In the design condition, the air guide is manufactured in a way so that it overlaps/intersects with the surrounding components 2) the air-guide is made flexible with a highly elastic rubber seal at the edge. When the air-guide is assembled, the rubber portion of the air-guide deforms to produce a proper fit leading to a sealed air-intake pathway. At high-speed condition as well as high airflow conditions by the radiator fan during idling/stationary, like DC charging – incase of BEV, etc., the air guide encounters high pressure. Being elastic and flexible, these conditions make the air guide susceptible to deformation with potential leakage of incoming air. Digital evaluation of the air guide deformation at different
GADASU, RAVISHASTRI, CHOUDHURY, SATYAJIT, Umesh, Acharya Vaibhav, Kumar, Saravanan, Yenugu, Srinivasa, Zander, Daniel, Beesetti, Siva, Hattarke, Mallikarjun
Aircraft and Aircraft Engine Fuel Pump Low Lubricity Fluid Endurance TestARP1797B (Current)11/26/2025
This procedure is intended to apply to fuel pumps. This procedure will be defined in terms of recommended test fluid, test setup, test conditions, and test method. This procedure may be used for other fuel system components, by testing in conjunction with the pump, which normally supplies the component inlet flow, or a substitute test pump of similar capacity. This procedure may be used, with variations in test conditions and test fluid for performing pump evaluation tests. Tests at progressively increasing pump speeds and pressures will provide design limitation data. Alternate test periods on a test pump and another pump, of a design for which actual service durability is known, will provide useful comparison data.
AE-5B Aircraft and Engine Fuel and Lubricant Sys Components
Performance Analysis of Graphene-Coated Heat Pipe Heat Exchangers for Automobile Exhaust Cooling and Purification2025-01-500601/23/2025
This research investigates the development of a heat pipe heat exchanger coated with graphene for cooling and purification of automobile exhausts. The heat exchanger directly affects the performance of the engine because proper heat dissipation and transfer can improve engine performance, reduce fuel consumption, and decrease the emission. Moreover, this effect is much more noticeable on coated heat pipes because of the enhanced thermal conductivity and mechanical properties of the graphene films. A heat null emitted by internal combustion engines was used in the experimental setup to test the thermal performance, cooling efficiency, and purification efficiency of the newly designed in-house exhaust simulation system where the new heat pipes were inserted. The results of the experiment show that the heat pipes have very high thermal performance as the efficiency of the heat pipes was calculated to be around 85%. Furthermore, the temperature decrease over the surfaces of the heat
Karthigairajan, M., Seeniappan, Kaliappan, Balaji, N., Natrayan, L., Sheik, Salman Basha, Ravi, D.
Modeling of Air Spring Dynamical Characteristics using Fractional Derivative Model and Thermal Hysteresis2025-01-004505/05/2023
Air springs are one of the most common used groups of vibration isolators and their dynamical characteristics are extensively studied. One of the main challenges of modeling of air spring dynamical characteristics is to model for hysteresis characteristics of air spring. Hysteresis characteristics of air spring are contributed by friction and viscosity of rubber bellow and by thermal hysteresis of compressed air inside air spring. In this paper, dynamic behaviors of air spring are modeled and analyzed. Firstly, force versus displacement data are obtained by the tests under static, harmonic and random excitations. Secondly, a nonlinear model is presented to capture the measured air spring’s behaviors. The model is consisted of Berg’s friction and fractional derivative model to describe rubber bellow behaviors and heat exchange model to describe thermal hysteresis of air. Furthermore, the proposed model parameters are identified using finite element model and test data. Finally, the air
Xia, Zhao
Noise analysis and optimization of thermal management integrated module2025-01-008105/05/2023
Abstract：The thermal management integration module is a multifunctional integrated component. The thermal management integration module includes water pumps, flow channel plates, brackets, sensors, etc. However, due to the large range of speed changes, the water pump will generate a wide range of frequency excitation. This excitation will cause the integrated module to vibrate and generate noise. This article studies and analyzes an integrated module that generates noise. An integrated module of a certain new energy vehicle is used as an example. Firstly, a vehicle experiment was conducted. It was found that the noise came from the integrated module. And then use finite element method to analyze the causes of noise generation. Based on the characteristics of multiple integrated module components, high integration degree, and complex structure. This article simplifies components such as brackets, heat exchangers, sensors, etc. And they are replaced by centralized quality points
XU, shenao
Design of Hybrid Air Conditioning System Using Phase Change Material for Commercial Sleeper Vehicles2022-28-044811/09/2022
Many road accident happens due to fatigue & deprive sleep of drivers. Many times driver use AC system for their quick thermal comfort during night with engine ON. This scenario is very critical from human's safety & vehicle functionality point of view. This also consumes additional 10-15% of fuel requirements in AC running condition. So, to address social problems of driver's sleep & pollution free environment by reducing the use of fossil there is a need of alternative techniques for air cooling which works during engine OFF condition. Various alternatives options for air cooling have been reviewed & extensive evaluations are mapped on the various performance parameters. Based on this the phase change material technology can be easily adopted due to its packaging flexibility. Phase change material (PCM) technology available in the market since decades for the use of storing the thermal energy. Perhaps the use of PCM material in controlled manner in not fully known for longer period of
Shalgar, Sandeep, Nagarhalli, Prasanna V, BEDRE, PALLAVI, SRIVASTAVA, SARVESH, Tupe, Akshay
Design Optimization and Thermal Simulation of a Plate Type Heat Exchanger (“Chiller”) for EVs Applications2022-28-044111/09/2022
The rapid evolution of electric vehicles (EVs) has considerably forced the automotive industry to design compact & highly efficient heat exchangers due to lower temperature applications. The plate type heat exchangers (Also known as "Chillers" in automotive industry) are one of the most important components in EVs thermal management systems. It is a type of heat exchanger, which uses metallic plates arranged like a staggered sandwiched structure to exchange heat between two working fluids. The heat transfer between the plates occurs due to highly compact structural design as compare to any conventional heat exchangers. The chiller is having very large surface area, which is exposed to the working fluids as the distribution happens all across the plates. The chillers are more suitable design for transferring heat between ranges of working fluids pressure varying from low to high pressures. Various types of welded, semi-welded plate heat exchangers are available. The working fluids flow
Suman, Saurabh, Kushwah, Yogendra Singh, SHUKLA, ANKIT, Singh, Shobhit Kumar
Proposed Standards And Methods For Leak Testing Lithium-Ion Battery Packs Using Glycol-based Coolant With Empirically Derived Rejection Limits2022-01-084803/29/2022
Lithium-ion batteries are a highly suitable energy source for many applications, particularly in the automotive sector due to their high energy density and low self-discharge rate. During the production of battery cells, rapid detection of leaks is essential to achieve necessary lifetime service-life and safety requirements. Once assembled into packs, whether made of prismatic, cylindrical or pouch cells, packs must be cooled by common automotive thermal management systems, for example those employing engine coolant and radiator, and in which manufacturers must prevent various leak-producing defects that affect durability, longevity and safety Two types of cooling systems are used in automobiles, an active variant in which refrigerant, compressor, evaporator and heat exchanger are used to operate the air conditioning system, or a passive variant with a cooling medium, typically a water/glycol mixture, and a heat exchanger cooled by ambient air. While good industry standards are
Wetzig, Daniel, Blaufuß, Marc
Flexible Reduced Order Modelling Applied to the Performance Optimization of a Catalytic Range Extender for Electric Vehicles2022-01-071803/29/2022
A major inhibitor to large scale adoption of battery electric transportation systems is their single-charge range. For passenger vehicles, limited charging infrastructure gives rise to range anxiety, whereas for commercial fleets, the higher cost of such vehicles still outweighs the gains from better overall efficiency and tax concessions. One way to mitigate such barriers is through the inclusion of a range extender in the drive train. These devices take on different forms, but generally offer improvements in the critical customer requirements of power-to-weight ratio and overall running cost. Delta-Cosworth have developed a catalytic range extender based on a recuperated Brayton cycle. This system comprises a rotating shaft on which are mounted a centrifugal compressor (φ 89.5 mm), a radial turbine (φ 106 mm), and an electric machine with an inverter to capture the net shaft power. Between the compressor and turbine, a heat exchanger raises the air temperature to 650°C followed by a
Mason, Alexander
Multiple Heat Exchangers for Automotive Systems – A Design Tool2022-01-020503/29/2022
A single radiator cooling system architecture has been widely applied in ground vehicles for safe equipment (e.g., engine block, electronics, and motors) temperature control. The introduction of multiple smaller heat exchangers provides additional energy management features and alternate pathways for continued operation in case of critical subsystem failure. Although cooling performance is often designed for maximum thermal loads, systems typically operate at a fraction of the peak values for most of their life cycle. In this project, a two-radiator configuration with variable flow rates and valve positions has been mathematically modelled and experimentally validated to study its performance feasibility. A multi-node resistance-capacitance thermal model was derived using the ε-NTU approach with accompanying convective and conductive heat transfer pathways within the system. This engineering model provides an analytical description of the system behavior that can be leveraged for
Syed, Zaker, Miller, Richard, Wagner, John
Modelling of a Transient VCRS and Virtual Optimal Charge Determination for Automobiles2021-28-025510/01/2021
Experimental research on the Vapor Compression Refrigeration System (VCRS) used in automobiles and other air conditioning systems is abundant in literature but it comes with inherent problems like the cost of the setup, time consumption, and tediousness of the process. Therefore, the objective of this study is to develop the fully-fledged transient or dynamic model of R134a based VCRS and further utilize it to virtually determine the optimal refrigerant charge quantity. The Simulink model developed in this work is an integration of physics-based mathematical models for each component (compressor, heat exchangers, and expansion valve), working together in a cycle where the compressor dictates the transient process. A sample simulation has been performed by taking 5 bar as the initial pressure of suction and discharge tanks and the steady state results (Discharge pressure, suction pressure, refrigerant mass flow rate, superheat and subcool temperatures) obtained. The results are found to
Bhala, Parth, ghosh, Anirban, Dixit, Manas, Gokavarapu, Srikar, Shangar Ramani, Vagesh
Advanced developments in solid desiccant coated heat exchangers and their potential applications2021-28-014209/15/2021
To meet the increasing thermal comfort requirements in recent times, applying a solid desiccant coated heat exchanger (SDCHE) air-conditioning system is one of the thrust areas of focus due to its energy efficiency benefits. Fixed stationary bed and rotary wheel desiccant systems are being used widely for dehumidification. In these systems, the increase in the relative humidity of intake process air increases the adsorption heat release from the desiccant, and the desiccant’s temperature increases due to the lower heat transfer efficiency. This effect reduces the COP of these systems since the desiccant adsorption capacity is inversely proportional to the desiccant’s temperature. To overcome the limitations of the fixed stationary beds and rotary wheel desiccant dehumidifiers, SDCHE is a suitable technology for standard vapor-compression air conditioners. These heat exchangers can deliver combined heat and mass transfer between the process air and the working fluid. The process air can
Muthu, Selvaraji, N, Sekarapandian, KANNAIYAN, Ashok, ARIVUKKARASU, Hariprasath
Method of improvement of air flow uniformity to reduce the evaporator frosting of a passenger car2021-28-014809/15/2021
For an efficient automotive HVAC system it is very essential to ensure uninterrupted and consistent airflow and temperature at the vent exit to help achieve the comfortable cabin space. This certainly requires temperature sensor to position at lowest possible temperature on heat exchanger and uniform flow distribution over it. However the uneven distribution of airflow on evaporator entry face leads to lowest temperature and sometimes goes undetected. This causes the condensate to get freezed and then frosting occurs at the core surface. Eventually a substantial portion of evaporator face gets choked and gradually airflow reduces and evaporator exit air temperature shoots up. Hence it is very important to prevent the frosting on evaporator core so to have uninterrupted airflow and adequate cooling in the passenger compartment. The present paper investigates the reasons for frosting occurring in one of the hatchback vehicle in bench test. The investigation consists of conducting anti
SEN, ANIT, SEN, SOMNATH, Parayil, Paulson, Goel, Arunkumar
The Role of Prototype/Test Systems in Next-Generation C5ISR DevelopmentTBMG-3825412/01/2020
Providers of C5ISR solutions often focus on the powerful deployable computer systems that provide superior performance capability. But to get to that end-design, there were prototyping/test systems that played a critical role in their development. It’s an important time for development systems as the military moves to more advanced modular open standard systems. This includes the SOSA/HOST/CMOSS efforts over the OpenVPX architecture, wideband testing via programable software defined radios (SDRs), and much more.
High-Performance, Lightweight, Easy-to-Fabricate Heat ExchangerTBMG-3819412/01/2020
Thermoelectric generator systems require high-performance hot-side and cold-side heat exchangers to provide the temperature differential needed to transfer thermal energy while withstanding temperatures up to 650 °C. Because the hot-side heat exchangers must have a high heat flux, they are often made of metals such as stainless steel or Inconel alloys.
Why Heat Exchanger Manufacturers Need to Rethink Design and FabricationTBMG-3822512/01/2020
Wherever oil, fuel, or electronics are located in a commercial or defense aircraft, spacecraft, or UAV, there’s likely a heat exchanger nearby. Some heat exchangers channel fuel stored in aircraft wings to cool the hot oil that lubricates the power system— as well as preheat the fuel on its way to the engines. Gearboxes produce an excess amount of heat that needs to be dissipated. And the increasing amount of electronics in modern aircraft must be precisely maintained at safe temperatures to function properly.
Getting to the ‘Core’ of AV Thermal Management20AVEP11_0511/01/2020
Data-gobbling processors require new cooling solutions - and the AV industry needs standards, says a veteran engineer. The universal understanding of autonomous vehicle safety is one of the most critical keys to broad adoption of self-driving technology. For AVs, what is “safe enough?” This understanding predicates the complement of sensors on the vehicle, which dictates the software and compute requirements, which allows for commoditization of the hardware. It's a domino effect. Quantifying or qualifying what is a “safe” autonomous platform requires industry-wide standards. When they are established, the rest will follow: sensor package requirements, computing requirements, commoditized hardware. Finally there is the real opportunity - the economization of AV manufacturing.
Shaw, Jim
Design and Analysis of Helical Baffled Shell and Tube Heat Exchanger Using Numerical Method2020-28-036209/25/2020
The ideology behind the project is to change the helical angle of the baffles that are attached to the heat exchanger so that it increases the flow rate of high viscous fluids. Thermo-water powered effectiveness examinations were done on five trisection helical confound heat exchangers with unmistakable tendency edges, puzzle shapes or contact examples, and one segmental astound heat exchanger (SEG). Examinations of thermo-water powered in general execution were performed on five trisection helical perplex warmness heat exchangers with exceptional tendency edges, confound shapes or association examples, and one segmental puzzle warmness heat exchanger (SEG). A relative assessment of three regions bewilder plans with tendency edges of 10 degree (10°S), 15 degree (15°S), and 20 degree (20°S); an oval confound conspire with a tendency edge of 15 degrees (15°E), and a hub cover area perplex plot with a tendency edge of 20 degrees (20°D) become executed. Nearby pictures had been built to
PERUMAL VENKATESAN, ELUMALAI, MASILAMANI, NAMBIRAJ, JAYADAS, JAYAKAR, Shajahan, Mohamed Iqbal, Murugesan, Parthasarathy, Varadharajan, Hariharan
The Use of CuO Nanoparticles as Additive to the Engine Coolant2020-01-223609/15/2020
Cooling is one of the most important processes conditioning proper operation of combustion engines. The development of the higher-power engines entails greater thermal loads, in which in turn require an increased cooling. The use of nanofluids (NFs) with admixture of metallic or nonmetallic nanoparticles (NPs) promises a potential platform for miniaturization of heat exchangers and/or lower energy consumption. This is attributed to an extended surface area related to NPs in the fluid, which allows for increase of thermal conductivity and a considerable increase of the heat transfer coefficient of the fluid with NPs. Their thermo-physical properties, such as particle size, stability, viscosity, dispersion, heat dissipation efficiency, zeta potential and thermal conductivity and also their behavior under different amount in the base fluid are systematically investigated from the point of view of the choice of the best candidate for coolant applied in modern engines. The CuO NPs turn out
Siczek, Krzysztof, Wozniak, Marek, Rylski, Adam
The Numerical Study on the Effect of CuO Nanoparticle Additive into SI Engine Coolant on the Engine Power2020-01-203209/15/2020
The goal of the study was to investigate the effect of different amounts of the CuO nanoparticles used as additive in the coolant on the power and efficiency of the analyzed SI engine. The temperature gradients in the engine body and its components were obtained using the elaborated model of the heat exchange in engine cooled with different fluids. The simplified model of combustion was used to estimate the temperature and power values generated during the combustion process in the engine under given load and speed values. The efficiency of the engine was estimated using the model taking into account various resistances generated during the operation of a given type of engine. The obtained changes in the engine power and efficiency resulted from the changed composition of the engine coolant were presented.
Siczek, Krzysztof, Wozniak, Marek, Diaconu, Mihai, Dima, Georgiana, Ion, Luiza, Bica, Ionela
Numerical Investigations on Heat Transfer and Flow Characteristics of Climate Control Systems in Electric Vehicles2020-28-001004/30/2020
Earth's surface temperatures would increase from 2.90 C to 3.40 C by the year 2100 due to global warming, leads to conceivable calamitous effects on human livelihoods, livestock, ecosystems and biodiversity. Overall globally several policies were made to reduce the carbon dioxide emission and other greenhouse gases. The transportation sector is one of the prominent sources of carbon dioxide emissions. On account of the significant emissions caused by conventional buses, migrating to electric buses which have zero tailpipe emissions for public transport fleets is essential. Taken into consideration of the energy density of traction batteries, and cost, energy utilized for HVAC applications should be optimized. Heat transfer and flow characteristics in the condenser and the evaporator zone of climate control system for electric buses were numerically studied and compared with experimental results. Grid independence and turbulence studies were carried out to develop the CFD methodology
Radha, Mahendravarman, S, Vijayaraghavan, D, Govindaraj, Radha, Mahendravarman, S, Vijayaraghavan, D, Govindaraj
Parametric Analysis of Impact of Geometrical Parameters on Thermal Performance in Compact Heat Exchangers2020-28-002504/30/2020
Compact heat exchangers are extensively used in the automotive sector, especially in engine cooling and passenger cabin cooling. Considering the evolution of compact heat exchangers from the past several years, development on the compactness has grown up rapidly with the market demand. In line with the futuristic view, it has become mandatory to optimize their thermal performance along with compactness, manufacturing feasibility and durability requirement. The present work investigates the impact of various geometrical parameters of tube & fin design on the heat transfer coefficient and pressure drop. The parametric study determines the most optimized core matrix by considering the manufacturing constraints using mathematical & analytical modeling. The system is mathematically modeled and then simulated to estimate the heat transfer rate, weight, free flow area, wetted area, etc. The output parameters are normalized with respect to the existing product performance benchmark and the
Nawani, Rachit, Suman, Saurabh, Kushwah, Yogendra Singh
Effect of Variable Geometry Fin in Automotive Condenser using Analytical and CFD Approach2020-28-002804/30/2020
Due to stiff competition among the Original Equipment Manufacturer (OEM's), the Comfort, Fuel efficiency & Safety are the key factors that drive the vehicle business, from that context Air Conditioning for a car plays a pivotal role in the area of comfort of the passengers and fuel efficiency point of view. In addition, condenser plays a pivotal role in Power train cooling system & air conditioning system. Therefore, it is a big challenge for the automotive engineer to propose an innovative design that can improve the thermal performance of Condenser without not compromise the package size. Also, it's a challenge for the OEM's to select the optimal heat exchanger from the supplier basket during the design phase of product development cycle. The objective of this paper to focus on analytical calculation or frame work was developed using excel tool considering the variable geometry of fin which includes louver pitch, louver angle and louver length in a multi-pass condenser. Further this
Anandan, Ram
UDM Tip Temperature Control using Thermosyphon Principle2020-28-004004/30/2020
In today’s automobile industry where BS6 is posing a high challenge and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and meeting challenging engineering requirement. Thus, the frugal engineering comes into the picture. An important technology that has come into highlight in recent years is the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other. The Flow through the UDM is maintained by changing Temperature (hence density) of the fluid at one end using the force airflow. The main objective of the
Solomon, Samson, Thiyagarajan, Rajesh, Khan, Parvej
Adaptation of Subcool Condenser for An Air Conditioning System Employing An Internal Heat Exchanger.2020-28-002604/30/2020
Recently, the use of air conditioning systems is growing rapidly due to increasing global temperatures. Considering enormous growth in the application of the air conditioning system, there is an urgent need to improve design, performance, and efficiency thereof. For example, the air conditioning systems that are being used these days are required to provide improved efficiency per unit of power consumed, and they are also required to have a smaller form factor as compared to conventional air conditioning systems. Therefore, a lot of modern air conditioning systems employ components such as internal heat exchangers, thermal expansion valves and forth to improve their performance while having a small form factor. In this study a condenser is adapted to be used for an air conditioning system employing an internal heat exchanger. Wherein the condenser subcool area is in a optimized range of a frontal condenser area; and a free flow area within the plurality of tubes of the subcool region
Suman, Saurabh, Kushwah, Yogendra Singh, maske, Suraj
Laboratory Testing of Vehicle and Industrial Heat Exchangers for Heat Transfer and Pressure Drop PerformanceJ1994_202004 (Current)04/28/2020
This SAE Recommended Practice is applicable to all heat exchangers used in vehicle and industrial cooling systems. This document outlines the tests to determine the heat transfer and pressure drop performance under specified conditions. This document has been reviewed and revised by adding several clarifying statements to Section 4.
Cooling Systems Standards Committee
Enhancement of Heat Exchanger Performance Using Oscillating Flow2020-01-094304/14/2020
In this research work, the heat transfer enhancement by using oscillatory flow of the thermal fluid between cold and hot reservoir has been analyzed both theoretically and using simulation methods. The main objective of this study is to examine the feasibility of a system working under oscillatory flow conditions compared to its steady flow counterpart. The principle of incrementing thermal diffusion over molecular diffusion by establishing oscillatory flow has been utilized in this case. The system has been designed and the effect of the flow condition has been analyzed using ANSYS Fluent k-epsilon model. The effect of change in the magnitude and frequency of oscillation on local Nusselt number has been computed. The observed increment in the Nusselt number by increasing the amplitude and frequency of the fluid has been bolstered by analytical calculation. A comparison in the heat transfer of a system working under oscillating and a steady flow conditions has been generated to
Rajagopalan, Haripriya, Premchandra Tavorath, Adhithiya, Pol, Sakshi, Dhamangaonkar, Pradyumna, Rajagopalan, Haripriya, Premchandra Tavorath, Adhithiya, Pol, Sakshi, Dhamangaonkar, Pradyumna
Transient Simulation of Heat Exchangers with Phase Change Material2020-01-015604/14/2020
Heat exchangers with Phase Change Material (PCM) are finding more energy storage applications for both Internal Combustion Engine Vehicles (ICEVs) and Electric Vehicles (EVs). These applications include cold storage evaporators for stop-start cars, thermal storage system for EV cabin heating and cooling, and other Heating, Ventilation, and Air Conditioning (HVAC) and Power Train Cooling (PTC) peak load shaving applications. The energy stored in a PCM heat exchanger is typically charged/discharged using refrigerant, coolant, or air, depending on the system design of different applications. Due to the low thermal conductivity of state-of-art PCM, the PCM heat exchangers generally rely on aluminum fins to enhance the speed of charging and discharging of the stored energy. Different fin shape, height and density will result in different PCM freezing/melting rate. In this paper, two different fin designs (folded-sine-wave fin and off-set-strip fin) are simulated with Computational Fluid
Xia, Yanping, Wolfe, Edward, Craig, Timothy
3-Dimensional Numerical Simulation on CuO Nanofluids as Heat Transfer Medium for Diesel Engine Cooling System2020-01-110904/14/2020
CuO-water nanofluids was utilized as heat transfer medium in the cooling system of the diesel engine. By using CFD-Fluent software, for 0.5%, 1%, 3% and 5% mass concentration of nanofluids, 3-dimensional numerical simulation about flow and heat transfer process in the cooling system of engine was actualized. According to stochastic particle tracking in turbulent flow, for solid-liquid two phase flow discrete phase, the moving track of nanoparticles was traced. By this way, for CuO nanoparticles of different mass concentration nanofliuds in the cooling jacket of diesel engine, the results of the concentration distribution, velocity distribution, internal energy variation, resident time, total heat transfer and variation of total pressure reduction between inlet and outlet were ascertained. It is proved by simulation results that nanofluids as heat transfer medium can evidently enhance diesel engine heat transfer capability, when the concentration of nanoparticles increases, the
Yang, Shuai, Yang, Xiaolin, Liu, Haifeng, Li, Xiuyuan
Adaptive sampling in the design space exploration of the automotive front end cooling flow2020-01-014904/14/2020
Adaptive sampling in the design space exploration of the automotive front end cooling flow (Author)Venkata Krishna Mohan Chagarlamudi, FCA NA - mohan.chagarlamudi@fcagroup.com, (Co-Author) Arturo Guzman FCA NA - arturo.guzman@fcagroup.com, (Co-Author) Mark Doroudian FCA NA - mark.doroudian@fcagroup.com, (Co-Author) Dr. Malik KAYUPOV Dassault Systemes Simulia Corp - malik.kayupov@3ds.com One of the key inputs 1-D transient simulation takes is a detailed front end cooling flow map. These maps that are generated using a full vehicle 3D CFD model require expensive computational resources and time. This paper describes how an adaptive sampling of the design space allowed the reduction of computational efforts while keeping desired accuracy of the analysis. The idea of the method was to find a pattern of DOE sampling points for 3D CFD simulations that would allow a creation of an approximation model accurate enough to predict output parameter values in the entire design space of interest
Chagarlamudi, Venkata KrishnaMohan, Doroudian, Mark, Kayupov, Malik, Guzman, Arturo
A Lumped-Parameter Thermal Model for System Level Simulation of Hybrid Vehicles2020-01-015004/14/2020
Commercial vehicle electrification is a path to meeting stringent fuel consumption and emission targets. Considering extended operations in different applications, the powertrain components need to be selected and sized together with the cooling system to ensure consistent performance and longer product life. In order to maintain the interactions between subsystems in the optimization routines, multi-physics models should be utilized. A simplified thermal network model is developed in this work for hybrid powertrain cooling systems based on the analogy between heat transfer and current flow equations. The assumption of a lumped system is valid for these components as the conductive heat transfer is much higher than convective heat transfer (Biot number <0.1). The energy equations are solved to calculate component temperatures in state space form, whereas, in literatures, detailed object-oriented 1-D models are mainly used for this purpose. This approach reduces simulation setup time
Caicedo Parra, Dina, Ramakrishnan, Kesavan, Farrell, Lisa, Narula, Manik, Sill, Patrick, Benjamin, Jithin
Thermal Performance Augmentation of Automobile Radiator Using Water-Based Al 2 O 3 and CuO Nanofluid as a Coolant2020-01-134004/14/2020
An engine cooling system in a vehicle engine is a must, which carries away unutilized heat produced in the engine cylinder. However, usage of low thermal conductivity engine coolant limits the ability of the cooling system to extract the heat, which ultimately results in difficulties in maintaining the compact size of the cooling system. Also, increasing the cooling rate by conventional technologies i.e. providing fins and microchannel has already reached their limits. Researchers are thus focusing on immersing and analyzing new types of cooling fluids in recent days. In the present study, the thermal performance of two different nanofluids, Al2O3 and CuO in a flat tube automobile radiator has been studied. Experimental results have been obtained for 0.02% volume concentration of both Al2O3 and CuO nanofluid, and water as coolants. A numerical model considering the ε-NTU method is also developed using MATLAB code. The analytical results are validated with experimental results. Further
Maisuria, Mahendrakumar, Rathod, Manishkumar K., Parmar, Akashkumar Pravinbhai
Rear Axle Heat Exchanger Utilization of Engine Coolant for Reduced CO2 Emissions and Fuel Consumption2020-01-141104/14/2020
This paper describes the design, development, and operation of a rear axle dual-shell heat exchanger on a RAM 1500 Light Duty truck. This system has been proven to increase fuel economy and reduce exhaust emissions, particularly CO2 on the EPA Cold City schedule. Through heat transfer math models, the energy conversion strategy will be explored. A PUGH analysis associated with concept selection is included. To refine the hardware and develop a control strategy prior to testing, a portable flow cart was developed to assess system performance and to correlate the multi-node heat transfer model. Bench testing focused on the durability and functional aspects of integrating the dual-shell axle cover with the axle and coolant delivery system through a comprehensive design and validation plan. Vehicle testing included various fuel economy and emissions related driving schedules to quantify the benefits.
Schumaier, Timothy, Bartlett, Matthew, Laugen, Alex, Scott, Timothy, Singh, Jasbir, Sopko, Jay, Troy, Paul
Utilization of bench testing in vehicle thermal system development for extreme cold ambient condition2020-01-139004/14/2020
Automotive thermal systems are becoming complicated each year. The powertrain efficiency improvement initiatives are driving transmission and engine oil heaters into coolant network design alternatives. The initiatives of electrified and autonomous vehicles are making coolant networks even more complex. The coolant networks these days have many heat exchangers, electric water pumps and valves, apart from typical radiators, thermostat and heater core. Some of these heat exchangers including cabin heaters deal with very small amount of coolant flow rates at different ambient conditions. This paper describes how viscosity can be a major reason for simulation inaccuracy, and how to deal with it for each component in the coolant network. Both experimental and computational aspects have been considered in this paper with wide range of ambient temperatures. Methods have been proposed to handle these issues in the simulation phase at the early phase of automotive thermal system development
Khandaker, Masuma, Uddin, Ahmed, Sanikal, Vijay, Fuad, Kaji, Lindquist, Craig, Baker, Gary, Rahman, Sadek
Thermal Considerations for IncubatorsTBMG-3641904/01/2020
Incubators, used for cell and tissue cultivation in hospital and laboratory settings, grow and maintain cell and tissue samples under controlled conditions for hours, weeks, or even months. They create the ideal environment for cell and tissue sample growth by maintaining optimum levels for temperature, humidity, carbon dioxide, and oxygen. Precision control of these factors enables research and experimental work in industries where cell culture is vital.
Accounting Thermal Exchanges in Coanda Effect2020-01-002603/10/2020
An exhaustive model of Coandã effect has not been defined, and fundamental questions are still open. One of them is the influence of convective heat exchange on Coandã adhesion. This paper presents an even preliminary numerical study of this problem. It analyses the behaviour of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface. It approaches the problem by a set of CFD simulations, analyses previous hypotheses, which are based on Prandtl number, and evidences the need for a model that account Reynolds number. The performed simulations are still not sufficient for an exhaustive comprehension of Coandã effect in the presence of heat exchange phenomena. It allows producing some consideration that may help future scientific work in toward a better comprehension of these phenomena. In particular, it verifies the importance of Reynolds number, because it is intrinsic in the adopted model, with good accordance with CFD data
Trancossi, Michele, Pascoa, Jose
EFFECT OF DEAN NUMBER ON HEAT TRANSFER CHARACTERISTICS FOR SQUARE CHANNEL HELICAL COIL SUB-COOLED CONDENSER2019-32-059701/24/2020
Attribute to high heat transfer rate and less complexity, the Helical coil sub-cooled condenser (HCSCC) can provide the most innovative and unique application for the air conditioning system. In the case of automobiles, reduction in air-conditioning load may diminish the vehicular emission, and power consumption as the air-conditioning load is the most power-consuming components after the engine load. Moreover, to solve the problem, we focus on the helical type heat exchanger. It may play a vital role in reducing the weight and increase the performance of the small engine because of the compact structure and lighter weight. The compressor unit is the most vital component of the refrigeration cycle, but the condenser unit is also one of the most critical devices, and the author tried to reduce the power consumption by enhancing the performance of the condenser. The crucial point of this study is to use HCSCC, which exemplify the effect of subsequent flow generation inside the fluid, and
Singh, Hardeep, Washiashi, Junya, Liu, Jun, Ichiyanagi, Mitsuhisa, Suzuki, Takashi
Mathematical Model of Heat-Controlled Accumulator (HCA) for Microgravity Conditions01-13-01-000101/20/2020
It is reasonable to use a two-phase heat transfer loop (TPL) in a thermal control system (TCS) of spacecraft with large heat dissipation. One of the key elements of TPL is a heat-controlled accumulator (HCA). The HCA represents a volume which is filled with vapor and liquid of a single working fluid without bellows. The pressure in a HCA is controlled by the heater. The heat and mass transfer processes in the HCA can proceed with a significant nonequilibrium. This has implications on the regulation of TPL. This article presents a mathematical model of nonequilibrium heat and mass transfer processes in an HCA for microgravity conditions. The model uses the equations of mass and energy conservation separately for the vapor and liquid phases. Interfacial heat and mass transfer is also taken into account. It proposes to use the convective component k for the level of nonequilibrium evaluation. The experiments were carried out in microgravity conditions for the estimation of the k value
Gennadiy Olexandrovich, Gorbenko, Polina Sergeevna, Koval, Konstantin Sergeevich, Yepifanov, Pavlo Grigorovich, Gakal, Rustem Yusufovich, Turna
Q&A: A Shape-Morphing, Self-Healing Soft CompositeTBMG-3578801/01/2020
Carmel Majidi, Professor of Mechanical Engineering at Carnegie Mellon University, and his team has developed a material with a unique combination of high electrical and thermal conductivity, with actuation and self-repair capabilities that are unlike any other soft composite.
Transport Method Boosts Capacity of Heat ExchangersTBMG-3572312/01/2019
Turbulent heat exchange is a method of heat transport widely used in heating, ventilation, and air conditioning (HVAC) systems. Adding a readily available organic solvent to common water-based turbulent heat exchange systems can boost their capacity to move heat by 500%. Other methods for increasing heat flux — nanoparticle additives or other techniques — have achieved about 50% improvement.
Reducing winter range loss for electric trucks19TOFHP12_0212/01/2019
Researchers at the Austrian Institute of Technology have developed an air exchange system that's capable of reducing heat load by 37% in real-world tests. Battery-electric vehicle (BEV) range loss from winter use of PTC (positive temperature coefficient) heating has become a source of major concern as the industry works to make EVs a mainstream choice. Addressing this particular problem area with an economically viable solution was deemed a worthwhile effort by the Austrian Institute of Technology (AIT), which is jointly owned by the Austrian government and the Federation of Austrian Industries. A fleet test of electric delivery trucks is underway on European roads. The AIT project, results of which were presented at the recent SAE Thermal Management Systems Symposium (TMSS), began by noting a 20% loss in range at −15°C (+5°F) from the heating system. AIT set a target of recovering 25% of that loss, primarily with the use of a ventilation module. Available reference data (at −10°C/+14
Weissler, Paul
Energy Recovery Rate from an Electric Air-Cycle System under the Cruising Altitude and Speed2019-01-190509/16/2019
A new electric air-cycle system of aircrafts is investigated focusing on energy recovery from the exhaust air. The working fluid of air has the higher energy level in the cabin than in the outside during the cruise because the outside air is at low pressure and low temperature. In the system, by setting a recovery turbine behind the cabin, the discharged energy can be collected, although the working fluid through the system has been only discharged from the cabin into the outside. We perform a thermodynamic cycle-analysis, where the temperature, pressure, entropy, etc. are calculated at each position of the cycle by considering the two pressure ratios of the compressors as variable parameters to show T-s diagram. In addition, we obtain an energy recovery rate of the recovery energy to the necessary power for the electric compressor. The energy recovery rate is roughly estimated 40-80% under the reasonable practical operating conditions.
Adachi, Takahiro, Seki, Naoki, Oyori, Hitoshi, Muraoka, Mikio
CFD Modeling of Compact Heat Exchangers for I.C. Engine Oil Cooling2019-24-017909/09/2019
This work describes the development of a computational model for the CFD simulation of compact heat exchangers applied for the oil cooling in internal combustion engines. Among the different cooler types, the present modeling effort will be focused on liquid-cooled solutions based on offset strip fins turbulators. The design of this type of coolers represents an issue of extreme concern, which requires a compromise between different objectives: high compactness, low pressure drop, high heat-transfer efficiency. In this work, a computational framework for the CFD simulation of compact oil-to-liquid heat exchangers, including offset-strip fins as heat transfer enhancer, has been developed. The main problem is represented by the need of considering different scales in the simulation, ranging from the characteristic size of the turbulator geometry (tipically μm - mm) to the full scale of the overall device (typically cm - dm). Therefore, the developed modeling approach is based on a multi
Della Torre, Augusto, Montenegro, Gianluca, Onorati, Angelo, Khadilkar, Sumit, Icarelli, Roberto
Heat Transfer Analysis of Catalytic Converters during Cold Starts2019-24-016309/09/2019
The transient heat transfer behavior of an automotive catalytic converter has been simulated with OpenFOAM in 1D. The model takes into consideration the gas-solid convective heat transfer, axial wall conduction and heat capacity effects in the solid phase, but also the chemical reactions of CO oxidation, based on simplified Arrhenius and Langmuir-Hinshelwood approaches. The associated parameters are the results of data in literature tuned by experiments. Simplified cases of constant flow rates and gas temperatures in the catalyst inflow have been chosen for a comprehensive analysis of the heat and mass transfer phenomena. The impact of inlet flow temperatures and inlet flow rates on the heat up characteristics as well as in the CO emissions have been quantified. A dimensional analysis is proposed and dimensionless temperature difference and space-time coordinates are introduced. Using this suitably modified coordinates, for the case of negligible axial solid conduction, computed solid
Papetti, Viola, Dimopoulos Eggenschwiler, Panayotis, Della Torre, Augusto, Montenegro, Gianluca, Onorati, Angelo, Koltsakis, Grigorios
Combustion Gas Heat ExchangerTBMG-3489708/01/2019
Two very challenging problems facing the U.S. and the world are energy security and global climate change, largely due to dependence on fossil fuels. Cost-effective technologies have been developed that are capable of substantial energy savings through improved energy efficiency.
Machining Capabilities Enhance Space-Related ProgramsTBMG-3473607/01/2019
Insaco Quakertown, PA
Performance of Additive Manufactured Stacks in a Small Scale Thermoacoustic Heat Engine2019-01-153406/05/2019
Thermoacoustic heat engines (TAHEs) are external combustion engines primarily designed to convert thermal power into acoustic power and, eventually, into mechanical, electric or other forms of high grade power. TAHEs rely on the presence of a porous core, often referred to as “stack”. A temperature gradient is established along the porous core and quasi-adiabatic heat exchanges occur between the solid walls of the pores and the surrounding gaseous medium undergoing pressure fluctuations. The internal geometry of the stack has tremendous impact on the efficiency of thermal-to-acoustic power conversion. In this study, the selective laser melting (SLM) has been used to produce stacks. The SLM is an additive manufacturing (AM) technique designed for 3D metal printing. It is based on high power- density laser which melts and fuses metallic powders together. Three sets of stacks, provided with different hydraulic radii and internal geometries, have been produced. Each set is constituted by
Auriemma, Fabio, Holovenko, Yaroslav
An Innovative Electric Motor Cooling System for Hybrid Vehicles - Model and Test2019-01-107604/02/2019
Enhanced electric motor performance in transportation vehicles can improve system reliability and durability over rigorous operating cycles. The design of innovative heat rejection strategies in electric motors can minimize cooling power consumption and associated noise generation while offering configuration flexibility. This study investigates an innovative electric motor cooling strategy through bench top thermal testing on an emulated electric motor. The system design includes passive (e.g., heat pipes) cooling as the primary heat rejection pathway with supplemental conventional cooling using a variable speed coolant pump and radiator fan(s). The integrated thermal structure, “cradle”, transfers heat from the motor shell towards an end plate for heat dissipation to the ambient surroundings or transmission to an external thermal bus to remote heat exchanger. A complete lumped parameter numerical modelling was implemented to estimate the thermal behavior of the corresponding electric
Shoai Naini, Shervin, Huang, Junkui (Allen), Miller, Richard, Wagner, John R., Rizzo, Denise, Sebeck, Katherine, Shurin, Scott
Development of a Correlation for Predicting Condensation Heat Transfer Coefficients for Refrigerant HFO-1234yf2019-01-015004/02/2019
Author has developed a correlation to predict condensation heat transfer coefficients for refrigerant condensation in an automotive parallel flow condenser. This is a first correlation in the open literature for HFO-1234yf to predict heat transfer coefficients for an automotive condenser. The system refrigerant mass flowrate was varied from 180 to 475 kg/hr; inlet refrigerant qualities from 1 to exit qualities of 0. The tests were conducted at an average condenser saturation temperature of 50°C and the oil circulation ratio was maintained at 3%.
Mathur, Gursaran D.
Metal 3D Printing for Complex Heat ExchangersTBMG-3415404/01/2019
Renishaw West Dundee, IL
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