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Polyamide 6(PA6)/hexagonal boron nitride(h-BN) and polyphenylene sulfide(PPS)/graphite composites have been prepared to investigate the possible usage as battery housing materials. The addition of the highly conductive filler improved thermal conductivity of polymer matrix more than 2 times. On the basis of the experimental results and intrinsic material parameters, thermal behavior in a battery pack has been monitored by computational simulation. The heat generated within a cell was readily dissipated as a highly thermal conductive aluminum(Al) was used and thus the temperature was evenly distributed over a whole package. In the case of a battery pack made of polymer or polymer composites, on the other hand, the temperature inside cell is much higher due to the accumulation of heat. The predicted heat flow behavior may be useful in selecting proper housing materials.

We used a one-dimensional monolithic catalyst model to predict the transient thermal and conversion characteristics of a dual monolithic catalytic converter with a Palladium only (Pd-only) catalyst and a Palladium/Rhodium (Pd/Rh) catalyst. Prior to the numerical investigation of the dual-catalyst converter, we modified the pre-exponential factor and activation energy of each reaction for both catalysts to achieve acceptable agreement with experimental data under typical operating conditions of automobile applications. We validated the conversion behavior of the lumped parameter model for each catalyst against different engine operating conditions. Two higher cell density substrates, Pd-only catalyst (600cpsi/3.9mil) and Pd/Rh catalyst (600cpsi/4mil), for faster light-off and improved warm-up performance are used in this study and the two monoliths has been connected without the space between monoliths.

In terms of the responsive quality of cars, reducing the vibration of car seats is very important, as this vibration is transmitted directly to the driver. Here, a sensitivity analysis method was used to reasonably reduce the vibration of car seats at minimal cost. A laboratory test was conducted under two excitation conditions: first, vibration in idle state; second, random vibration not exceeding 100 Hz. To determine the reliability of the laboratory test, the actual vibration in idle state was simulated in a multi-axial simulation table for the idle excitation environment of cars that are sensitive to even the smallest changes in the environment. The frequencies of interest were selected by adding the sums of frequency response functions measured at the 24 nodal points of interest under the two excitation conditions.

This paper presents an analytical modeling and performance analysis of the hydraulic engine mount by using bond graph method, which is becoming more common in the industry for engine vibration and noise control. It is well known that the hydraulic engine mount can provide excellent frequency and amplitude response characteristics compared to the conventional elastic rubber type one. Numerous study has been attempted up to now to explain the complex dynamic performance characteristics of this mount through a variety of analytical methods but it is not yet fully understood.

A thermal fluid flow analysis for multiflow channel(MFC) condenser for automotive air-conditioning system using HFC-134a refrigerant has been carried out. The present study has been done as a part of the work intended to develop a design tool of HFC-134a refrigerant air conditioning system for passenger vehicle by applying a steady state simulation scheme to obtain the performance optimization. Thermodynamic and flow properties of HFC-134a refrigerant and temperature profile of the air flow over the surface of MFC condenser are predicted as a function of flow channel distance using a model of finite difference method. Variations of the heat transfer rate and pressure distribution are predicted under consideration of the actual multiflow channel constructions. The results of the predicted analysis obtained from the simulation analytical model were found to be conform with the known actual operation conditions of HFC-134a condenser in passenger vehicle air conditioning system.

This paper describes real-time hardware-in-the-loop simulator using the RT-Lab, Simulink and Bikesim to simulate an each major part of electric bike system in real time. The major components of electric powered bike system consist of a PMSM fed by a 3 phase MOSFET inverter, battery and main controller. SimPowerSystem that is one of the toolbox of the Matlab/Simulink is used for modeling and simulation of power components. Each major electric component of the electric powered bike is modeled by Model-Based Design (MBD) method with Simulink. Interworking methods between software such as battery, motor/inverter, bike dynamics model and hardware such as battery, motor/inverter, power supply, electric loader are also described for real-time hardware-inthe- loop simulation based on RT-Lab and Simulink. Especially, this paper describes how to assess the performance of each component with rest of the electric parts in real time.

The optimum design process of the low-temperature condenser of a dual-loop waste heat recovery system with Rankine steam cycles for improving the fuel efficiency of gasoline automobiles has been investigated. The waste heat recovery system consists of a high-temperature (HT) loop in which water as the HT working fluid recovers waste heat only from the exhaust gas of about 700°C and a low-temperature (LT) loop in which a refrigerant as the LT working fluid recovers heat dissipation from the HT loop, and waste heat from the engine coolant of relatively low temperature. The low temperature condenser plays a role to dissipate heat from the system by condensing the low temperature loop working fluid sufficiently.

A technique to inject fault conditions into a control board of a DC-DC converter and evaluate required functionality by using a hardware-in-the-loop (HIL) simulation is presented in this paper. The power stage of a DC-DC converter and a battery are designed by Xilinx System Generator. Whole models and the special-purpose peripherals between the control board and HIL simulator are all implemented into the FPGA for fault test. The each model on FPGA has a flexible, modular and reusable structure where the designer can customize the hardware model by changing primary parameters. HIL implementation is discussed. Fault injection test based on HIL simulation is shown to explore the useful technique indispensable to validating the predefined protection algorithm at abnormal temperatures and voltages.

This paper deals with acquisition of the material properties of the thermosetting plastic reinforced with various laminating angles of carbon fibers in order to apply to structural analysis of steering system components. The laminating carbon composites are manufactured as stacking uni-direction carbon prepreg with various fiber orientations from 0 to 90 degree and applying heat and pressure by hot press. We evaluate the modulus and ultimate strength of the CFRP according to the fiber orientation through uniaxial tensile test (ASTM 3039). The composite material shows the strong anisotropic properties according to loading direction. In order to describe the material behavior accurately, the anisotropic material behavior is numerically formulated and for the verification of analysis scheme which is applied in this paper, analysis results of uniaxial tension process of composite material with various fiber orientations are compared with that obtained from the experiments.

The strict new emission regulations have resulted in the development of new techniques to meet the control of cold-start emission in various competitive ways. In this study, the dual walled air gap exhaust pipe system is developed as an effective countermeasure to reduce pollutant exhaust gas emission, particularly to reduce pollutant exhaust gas emission at cold start and idling stage, in which the catalytic converter has not reached to light-off temperature. In this study, it is shown that dual walled air gap exhaust system can shorten the time to reach to light off temperature of the catalytic converter in cold start state, and reduce the emission of Hydrocarbon (HC) significantly due to its low thermal capacity and high thermal insulation effect. In the study, a thermal analysis of the dual walled air gap exhaust pipe system has been done using the computational fluid dynamics method.