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Training / Education
2014-10-20
Vehicle functional requirements, diesel emission regulations, and subsystem thermal limits all have a direct impact on the design of a powertrain cooling airflow system. Severe duty cycles, minimal ram air, fouling, and sometimes unconventional package layouts present unique challenges to the designer. This webinar introduces many airflow integration issues and vehicle-level trade-offs that effect system performance and drive the design. The goal of this six-session webinar is to introduce engineers and managers to the basic principles of diesel cooling airflow systems for commercial and off-road vehicles. Participants will learn about vehicle/product constraints, integration issues, cooling airflow, system resistance, fans, shrouds, radiators, coolers, estimating heat rejection, thermal recirculation, and overall system performance. Basic concepts will be reinforced with examples and a cooling performance calculation of a diesel cooling system. SAE Papers 2002-01-0256, 850281, 900001 and 740691 are included as references in the course materials.
Training / Education
2014-09-25
Rapid advances have been made in the range of available designs and operational parameters as well as in the fundamental understanding of compact heat exchangers (CHEs). Since the majority of modern heat exchangers used for heating and cooling systems for vehicular applications are CHEs, keeping up to date with these advances is essential. This seminar will help you understand and be able to apply comprehensive information about the intricacies of CHE design, performance, operating problems and state-of-the-art-technology for car and truck applications.
Event
2014-09-22
WIP Standard
2014-04-16
This SAE recommended Practice is intended for use in testing and evaluating the approximate performance of engine cooling fans. This performance would include flow, pressure, and power. This flow and pressure information would then be used to estimate the engine cooling performance. This power consumption would then be used to estimate net engine power per SAE J1349. The procedure also provides a general description of equipment necessary to measure the approximate fan performance. The test conditions in the procedure generally will not match those of the installation for which cooling and fuel consumption information is desired. The performance of a given fan depends on the geometric details of the installation, including the shroud and its clearance. These details should be duplicated in the test setup if accurate performance measurement is expected. The performance at a given air density and speed also depend on the volumetric flow rate, or the pressure rise across the fan, since these two parameters are mutually dependent.
WIP Standard
2014-04-04
This SAE Aerospace Standard (AS) defines the requirements for polytetrafluoroethylene (PTFE) line, metallic reinforced, hose assemblies suitable for use in aerospace hydraulic, fuel and lubricating oil systems at temperatures between -67 °F and 450 °F for Class I assemblies, -67 °F and 275°F for Class II assemblies, and at nominal pressures up to 1500 psi. The hose assemblies are also suitable for use within the same temperature and pressure limitations in aerospace pneumatic systems where some gaseous diffusion through the wall of the PTFE liner can be tolerated.

The use of these hose assemblies in pneumatic storage systems is not recommended. In addition, installations in which the limits specified herein are exceeded, or in which the application is not covered specifically by this standard, for example oxygen, shall be subject to the approval of the procuring activity.

WIP Standard
2014-04-02
This SAE Standard covers reinforced hose, or hose assemblies, intended for conducting liquid and gaseous dichlorodifluoromethane (refrigerant 12) in automotive air-conditioning systems. The hose shall be designed to minimize permeation of refrigerant 12 and contamination of the system and to be serviceable over a temperature range of -30 to 120 °C (-22 to 248 °F). Specific construction details are to be agreed upon between user and supplier. NOTE— SAE J2064 is the Standard for refrigerant 134a hose. For refrigerant 134a use, refer to SAE J2064
WIP Standard
2014-04-02
This SAE Recommended Practice is used for establishing the compression set that could be expected to occur with engine coolant hoses under securing clamps. It seeks to reproduce the type of indentation caused by the clamps in the wall of the hose. An excessive compression set measured by this method would indicate a hose that could eventually alloy leakage of coolant past the clamps in service. This method has been found to give repeatable results in the range of 25% to 50% initial compression.
WIP Standard
2014-04-02
The Measurement of Coolant Hose task group conducted a round-robin study to determine the measuring capability of automotive suppliers and users to measure Inside Diameter (ID), Outside Diameter (OD), Wall Thickness (Wall) and wall thickness variation of hose using traditional measuring devices and techniques. Seven companies (five suppliers and two end users) participated in this testing. Based upon the round-robin study this information report will detail procedures, test measuring devices, results and recommendations.
WIP Standard
2014-04-02
The Hose Measurement Task Force conducted a round-robin study to determine the measuring capability of automotive suppliers and users to simultaneously measure the Inside Diameter (ID), Outside Diameter (OD), Wall Thickness (Wall), and Wall thickness Variation (WV) of hose using a laser-based, non-contact LOTIS QC-20 gauging device. Three (3) companies (all end users) participated in this testing with one of the three companies performing the GR&R calculations presented herein. Based upon the round-robin study this report will detail procedures, test measuring devices, results, and conclusions.
Technical Paper
2014-04-01
Youcai Liang, Gequn Shu, Hua Tian, Haiqiao Wei, Xingyu Liang, Mingru Zhao
Abstract Cogeneration system has become a valuable alternative approach for cascade waste heat recovery (WHR). In this paper, a novel electricity-cooling cogeneration system (ECCS) based on organic Rankine cycle-absorption refrigeration cycle (ORC-ARC) combined system is proposed to recover the waste heat of marine engine. ORC was adopted in the higher temperature cycle, in which alternatives D4, MDM and MM were selected as the working fluids. An ARC was adopted in the lower temperature cycle to recover the heat of the working fluid at the regenerator outlet in ORC. It aims to satisfy refrigeration requirement aboard ship, in which a binary solution of ammonia-water is used as the working pairs. Electricity output, cooling capacity, total exergy output, primary energy ratio (PER) and exergy efficiency are chosen as the objective functions. The results show that the additional cooling capacity is up to 10.9 MW, and such an ECCS has improved the exergy efficiency by 51% compared to the basic ORC.
Technical Paper
2014-04-01
Marcus Becher, Stefan Becker
Abstract This paper focuses on the applicability of numerical prediction of sound radiation caused by an axial vehicle cooling fan. To investigate the applicability of numerical methods, a hybrid approach is chosen where first a CFD simulation is performed and the sound radiation is calculated in a second step. For the acoustic simulation an integral method described by Ffowcs-Williams-Hawkings is used to predict the sound propagation in the far-field. The simulation results are validated with experiments. The corresponding setup in experiments and simulation represents an overall system which includes the cooler, the cooling fan and a combustion engine dummy. To optimize the economical applicability in terms of simulation setup and run time, different approaches are investigated. This includes the simulation of only one blade using a periodic boundary condition as compared to the whole fan geometry. In the CFD simulation an SAS-turbulence-model is applied. The results show that this is a very useful approach considering the challenges in prediction of numerical sound.
Technical Paper
2014-04-01
Matthieu De Maillard, Mehrdad Zangeneh
Abstract In many automotive highway/off-highway engine cooling applications the fan has to provide a fairly large pressure rise and operate with a large gap between the tip of the blade and the shroud surface (tip clearance). This can pose difficult design challenges. This paper presents a design process coupling 3D inverse design with a Multi Objective Genetic Algorithm (MOGA) for an axial cooling fan. The aim is to reduce the leakage loss and profile losses to improve performance. The inverse design method parameterizes the 3D shape of the axial fan with a reduced number of design parameters allowing a larger exploration of the design space in the optimization process. The methodology is applied to the design of a highway truck engine cooling fan with a tip gap of 8% of blade height. Two designs from the optimization are analyzed in detail using 3D Computational Fluid Dynamic (CFD) simulations, confirming that the design optimized for minimizing leakage losses meets the design specification.
Technical Paper
2014-04-01
Huize Li, Predrag Hrnjak
Abstract The effect of lubricant on distribution is investigated by relating the flow regime in the horizontal inlet header and the corresponding infrared image of the evaporator. Visualization of the flow regime is performed by high-speed camera. R134a is used as the refrigerant with PAG 46 as lubricant, forming foam in all flow regimes. Quantitative information including foam location, foam layer thickness is obtained using a matlab-based video processing program. Oil circulation rate effect on flow regime is analyzed quantitatively.
Technical Paper
2014-04-01
Kambiz Jahani, Sajjad Beigmoradi
The efficiency of the vehicle cooling system strongly depends on the air flow through the radiator core. The flow through the radiator core in turn depends on other panels that are in the vicinity of the radiator. In this study, the effect of geometrical change at vehicle front-end including the whole bonnet, grille and bumper area is investigated by means of Computational Fluid Dynamics (CFD). Numerical modeling is carried out by means of CAE tools. Simulations are performed for maximum power and maximum torque conditions, monitoring the mass flow rate through the radiator core and velocity contribution over the radiator face. To the velocity field of the airflow, the heat exchangers are represented as porous media and fan module is modeled utilizing Multiple Reference Frame (MRF) approach. The validity of the developed simulation capability is tested by successful comparison with the available experimental data for the base model at the given operating conditions. On studying the model with complete new front-end style, local modifications are applied incorporating adding airguide, flap and anti-recycler in order to enhance the flow distribution in the vicinity of radiator and increase the mass flow rate passing through it.
Technical Paper
2014-04-01
C. Scott Sluder, John M.E. Storey, Michael J. Lance
Abstract Fouling in EGR coolers occurs because of the presence of soot and condensable species (such as hydrocarbons) in the gas stream. Fouling leads to one of two possible outcomes: stabilization of effectiveness and plugging of the gas passages within the cooler. Deposit formation in the cooler under high-temperature conditions results in a fractal deposit that has a characteristic thermal conductivity of ∼0.033 W/m*K and a density of 0.0224 g/cm3. Effectiveness becomes much less sensitive to changes in thermal resistance as fouling proceeds, creating the appearance of “stabilization” even in the presence of ongoing, albeit slow, deposit growth. Plugging occurs when the deposit thermal resistance is several times lower because of the presence of large amounts of condensed species. The deposition mechanism in this case appears to be soot deposition into a liquid film, which results in increased packing efficiency and decreased void space in the deposit relative to high-temperature deposits.
Technical Paper
2014-04-01
Michael J. Lance, John Storey, Sam Lewis, C. Scott Sluder
Abstract All high-pressure exhaust gas recirculation (EGR) coolers become fouled during operation due to thermophoresis of particulate matter and condensation of hydrocarbons present in diesel exhaust. In some EGR coolers, fouling is so severe that deposits form plugs strong enough to occlude the gas passages thereby causing a complete failure of the EGR system. In order to better understand plugging and means of reducing its undesirable performance degradation, EGR coolers exhibiting plugging were requested from and provided by industry EGR engineers. Two of these coolers contained glassy, brittle, lacquer-like deposits which were analyzed using gas chromatography-mass spectrometry (GC-MS) which identified large amounts of oxygenated polycyclic aromatic hydrocarbons (PAHs). Another cooler exhibited similar species to the lacquer but at a lower concentration with more soot. The authors propose that lacquer deposits form when oxygenated PAHs present in the exhaust condense on the cooler walls subsequently experience nitric acid catalyzed polymerization in the presence of aldehydes.
Technical Paper
2014-04-01
Felix Regin A, Abhinav Agarwal, Niraj Kumar Mishra
Abstract Increased engine thermal load, front end styling and compact vehicle requirements have led to significant challenges for vehicle front end designer to provide innovative thermal management solutions. The front end cooling module design which consists of condenser, radiator, fan and intercooler is an important part of design as it ensures adequate heat removal capacity of radiator over a wide range of operating conditions to prevent overheating of engine. The present study describes the optimization of cooling air flow opening in the front end using CFD methodology of a typical passenger car. The predicted vehicle system resistance curve and coolant inlet temperature to the radiator are used for the selection of cooling modules and to further optimize the front end cooling opening area. This leds to the successful optimization of the front end, selection of cooling modules with significant cost savings by reducing prototype testing and design cycle time.
Technical Paper
2014-04-01
Michael J. Lance, Hassina Bilheux, Jean-Christophe Bilheux, Sophie Voisin, C. Scott Sluder, Joseph Stevenson
Abstract Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with NOx emissions standards. Exhaust gas laden with particulate matter flows through the EGR cooler which causes deposits to form through thermophoresis and condensation. The low thermal conductivity of the resulting deposit reduces the effectiveness of the EGR system. In order to better understand this phenomenon, industry-provided coolers were characterized using neutron tomography. Neutrons are strongly attenuated by hydrogen but only weakly by metals which allows for non-destructive imaging of the deposit through the metal heat exchanger. Multiple 2-D projections of cooler sections were acquired by rotating the sample around the axis of symmetry with the spatial resolution of each image equal to ∼70 μm. A 3-D tomographic set was then reconstructed, from which slices through the cooler sections were extracted across different planes. High concentrations of hydrocarbon is necessary for imaging deposits and only those coolers which exhibited large organic fractions or hydrated sulfate phases were successfully characterized.
Technical Paper
2014-04-01
Yuji Kobayashi, Kenji Yoshida, Hideaki Nagano, Itsuhei Kohri
A cooling fan is one of the primary components affecting the cooling performance of an engine cooling system. In recent years, with the increase in electric vehicles (EVs) and hybrid vehicles (HVs), the cooling performance and noise level of the cooling fan have become very important. Thus, the development of a low-noise fan with the same cooling performance is urgently required. To address this issue, it is critical to find the relation between the performance of the fan and the flow structures generated around it, which is discussed in the present paper. Specifically, a computational method is employed that uses unsteady Reynolds-averaged Navier-Stokes (URANS) coupling with a sliding mesh (SLM). Measurements of the P-Q (Pressure gain-Flow rate) characteristics are performed to validate the predictive accuracy of the simulation. Additionally, proper orthogonal decomposition (POD) is employed to analyze the unsteady data obtained by URANS calculations to reveal the typical flow structures.
Technical Paper
2014-04-01
Nikolaos Karras, Timo Kuthada, Jochen Wiedemann
Abstract The increasing importance of electric mobility results into the need for optimizing all power train components to further reduce the energy consumption of the vehicle. The aim of this study is to predict the thermal behavior and the pressure losses in water jackets of electric machines by use of CFD. The heat loss of electric machines in passenger cars is sufficient to let its components reach critical temperatures. For this reason, the optimization of heat dissipation plays an important role. The goal of efficient heat dissipation is a high heat transfer coefficient. At the same time, the pressure loss should be low in order to reduce the required power of the pump. Flow simulations can help to evaluate different water jacket concepts in an early stage of development. In this work, the validation of flow simulations in water jackets is based on measurements of a simplified geometry with constant boundary conditions. Afterwards, a coupled flow simulation of Exa PowerFLOW® and Exa PowerTHERM® is set up with the boundary conditions adopted from the measurements.
Technical Paper
2014-04-01
Vinod Kumar Srinivasa, Renjith S, Biswadip Shome
Abstract Increasing demands on engine power to meet increased load carrying capacity and adherence to emission norms have necessitated the need to improve thermal management system of the vehicle. The efficiency of the vehicle cooling system strongly depends on the fan and fan-shroud design and, designing an optimum fan and fan-shroud has been a challenge for the designer. Computational Fluid Dynamics (CFD) techniques are being increasingly used to perform virtual tests to predict and optimize the performance of fan and fan-shroud assembly. However, these CFD based optimization are mostly based on a single performance parameter. In addition, the sequential choice of input parameters in such optimization exercise leads to a large number of CFD simulations that are required to optimize the performance over the complete range of design and operating envelope. As a result, the optimization is carried out over a limited range of design and operating envelope only. In this paper, a Design of Experiments (DoE) based CFD approach has been used to optimize the fan and fan-shroud design of a cooling pack system.
Technical Paper
2014-04-01
Wilko Jansen, Joe Amodeo, Edward Tate, Zhongzhou Yang
Abstract In a tiered cooling pack, the airflow through the individual heat exchangers is determined by the package and aperture lay out. Each heat exchanger rejects heat as a function of the internal coolant flows, the cooling airflow and the air temperature. In a typical automotive cooling pack, the cooling airflow will be non-uniform in velocity and temperature due to fans, aperture geometry, exterior flows, heat exchangers and recirculation. In a drive cycle, these boundary conditions will change with vehicle operating conditions like vehicle speed, engine speed, ambient temperature, and altitude. These non-uniform conditions on the cooling pack can lead to significant errors when uniform boundary conditions are assumed in a transient simulation. This error is commonly corrected using vehicle test data. A predictive approach, which eliminates the need for correlation vehicle testing, is presented. This methodology uses a full vehicle airflow simulation in PowerFLOW to determine boundary conditions at the entrance and exit of the cooling package at stabilized operating conditions.
Technical Paper
2014-04-01
Hideo Yoshida, Hiroyuki Nakayama, Yukio Mizukoshi, Yasuyuki Asahara
Abstract This paper reports about a trial for miniaturization of an air-cooled inverter integrated with motor, which is realized by reduction of the total volume of smoothing capacitor. An integrated system prototype was constructed with a disk-shaped inverter positioned at the rear end of the motor. We examined the possibility of using a ceramic capacitor, which features a higher heat-resistance temperature, lower internal resistance and higher capacity density than a film capacitor. At the same level of capacitance, the volume of a ceramic capacitor is less than one-half that of a film capacitor, enabling the size of the smoothing capacitor to be reduced to approximately one-fifth that of the currently used device. A suitable circuit configuration and physical layout of distributed smoothing capacitors and corresponding power device modules are proposed and demonstrated.
Technical Paper
2014-04-01
Cornelius Pfeifer
Abstract Automotive manufacturers are looking for ways to reduce the CO2 emissions of their vehicle fleet. Increasingly, OEMs are focusing on intelligent air flap systems, which enable high cooling capacity through maximum air flow when they are in an open position. In a closed position, they reduce drag and the time necessary to bring the engine up to operating temperatures. Electric vehicles like the Tesla S benefit from Röchling's Active Grille Shutters (AGS) with a total of four independently controlled flap systems and the new generation of actuators. The module extends the driving range through improved aerodynamics and ensures optimized battery cooling and temperature control. Maximum benefit can be achieved if the controlled air flap systems are mounted right in the front to optimize aerodynamics. While adaptive air flap systems are increasingly used to improve aerodynamics today, they can be a key component of a future thermoacoustic engine encapsulation. This presentation is giving an overview about the current active grille shutter systems as well as a prospect for further CO2 reduction when integrated into a thermoacoustic engine encapsulation.
Technical Paper
2014-04-01
Xu Song, John Myers, Scott Sarnia
The Low Temperature Cooling (LTC) system is commonly developed for secondary cooling function requirements, such as forced induction air cooling, and HEV power electronics module cooling. The large heat transfer capacity of coolant allows for very compact water-cooled heat exchangers to be installed remotely for better underhood aerodynamic characteristics and more compact packaging design. An integrated LTC loop developed on a Hyundai 2.0L Turbo Charged vehicle extends a traditional WCAC (Water-cooled charged air cooler) application to include a water-cooled condenser (WCOND) module. Unlike other published LTC system design approaches, this research project emphasizes underhood airflow improvement strategy and focuses on heat transfer efficiency. This paper discusses the integrated LTC loop configuration, Low Temperature Radiator (LTR) design, coolant flow control, and others. The LTC system prototype design allowed vehicle performance data to prove that a simplified front end cooling module package allows better airflow cooling efficiency.
Technical Paper
2014-04-01
Michael Bassett, Jonathon Hall, Marco Warth, Andreas Eilemann, Christian Merkle
Abstract In a typical plug-in hybrid electric vehicle (PHEV) installation, there exist multiple, potentially separate, cooling circuits. These circuits may have individual cooling/heating requirements or they may have common aspects. Opportunities exist for combining circuits for series applications for cost, weight and efficiency benefits. However, careful consideration must be paid to the compatibility of these circuits both in terms of temperature range requirements, but also in terms of the thermal loading of the systems on the cooling circuits. This paper presents details of a cooling system for a PHEV demonstrator recently completed by MAHLE Powertrain. The opportunities for the integration of several cooling circuits, including the cabin heating, ventilation and air-conditioning (HVAC) system, to optimise the system from a cost, package-space and weight perspective are discussed. Furthermore, the opportunities for the pre-conditioning and operating strategies for the complete cooling/heating system, from a holistic vehicle efficiency perspective, are also briefly outlined.
Technical Paper
2014-04-01
Ivan Arsie, Andrea Cricchio, Vincenzo Marano, Cesare Pianese, Matteo De Cesare, Walter Nesci
This paper deals with modeling and analysis of the integration of ThermoElectric generators (TEG) into a conventional vehicle, specifically aimed at recovering waste heat from exhaust gases. The model is based on existing and commercial thermoelectric materials, specifically Bi2Te3, having ZTs not exceeding 1 and efficiency below 5%, but a trade-off between cost and performance that would be acceptable for automotive applications. TEGs operate on the principle of thermoelectric energy conversion via Seebeck effect, utilizing thermal gradients to generate electric current, with exhaust gases at the hot side and coolant at the cold side. In the simulated configuration the TEG converters are interfaced with the battery/alternator supporting the operation of the vehicle, reducing the energy consumption due to electrical accessories and HVAC. Heat exchanger models for steady-state solutions have been simulated to estimate the actual temperature of hot and cold sides, as a function of vehicle operation and TEG configuration.
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