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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.

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.

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.

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.

In this study a new model is proposed for turbulent premixed combustion in a spark-ignition engine. An independent transport equation is solved for the mean reaction progress variable in a propagation form in KIVA-3V. An expression for turbulent burning velocity was previously given as a product of turbulent diffusivity in unburned gas, laminar flame speed and maximum flame surface density. The model has similarity with the G equation approach, but originates from zone conditionally averaged formulation for unburned gas. A spark kernel grows initially as a laminar flame and becomes a fully developed turbulent flame brush according to a transition criterion in terms of the kernel size and the integral length scale. Simulation of a homogeneous charge pancake chamber engine showed good agreement with measured flame propagation and pressure trace. The model was also applied against experimental data of Hyundai θ-2.0L SI engine.

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.

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.

A preliminary study was conducted to develop an automotive thermal energy storage unit for reduction in emissions and for increase in occupants comfort in winter. To prevent thermal storage performance degradation of the thermal storage media some additives were mixed with the base material Bariumhydroxide-octahydrated(Ba(OH)2·8H2O), and offers promising degradation-resist characteristics. The thermal energy storage unit was then optimally designed based on parameter study and empirical analysis. A comparison was made with a commercially available heat battery. Peak power of the developed thermal energy storage unit was about three times higher than that of the existing one.

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.