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This paper deals with the Real Time Simulator concerned with entire physical values applied to the automatic climate control for the vehicle, the automatic climate controller and the temperature variation of cabin inside. The control performance is under the characteristics of HVAC system, cabin structure, thermal loads from cabin outside and control algorithm. However, one of the biggest problem with automatic climate control is that it requires a heavy cost and much time for the experimental verification. Moreover, CFD cannot afford to analyze all these values perfectly. For this reason, we solved this problem through the simplified mathematical model and the equations which are evaluated from experimental background. The main objective of this study is to develop a simulator which can replace actual vehicle test on automatic climate control thoroughly.

In this paper, we deal with the automatic climate control for Recreational Vehicle (RV). The HVAC system used for RV was composed of front side and rear side. And, the HVAC system of front side differed from that of rear side in the characteristic of HVAC system. This system was economically optimized for automatic control over 2 separated zones. The development procedure of automatic climate controller was as follows. The first stage was to derive control equation from characteristic analysis of HVAC system and the structural characteristic of vehicle interior. In the second stage, the software (S/W) was designed and programmed to operate microprocessor which calculated previously mentioned equation. Finally, the hardware (H/W) design and building were performed to operate the HVAC system with the calculation results from microprocessor. The control performance of this automatic climate control algorithm and system was evaluated by experimental method.

An upgraded multizone model is developed in order to study the effects of fuel injection characteristics on DI diesel engine soot and NOx emissions. Effects of fuel spray characteristics, the movement and evaporation of droplet, and spray wall impingement are considered. NOx emission is predicted by the extended Zeldovich mechanism and soot emission is simulated by the current soot formation and oxidation model. The multizone model can be used to calculate cylinder pressure, heat release rate, engine performance, NOx and soot emissions, etc. In this paper, the boot injection and split injection are simulated. The simulation shows that the fuel injection characteristics have significant effects on the process of engine combustion and emissions. The NOx and PM emissions from DI diesel engine can be reduced simultaneously by optimizing the shape of injection rate, especially by boot injection.

This paper is consists of two parts, which describe the development procedure of climate control algorithm for a passenger car. The first part deals with the control algorithm design, and the second part introduces control performance test. Control algorithm is evaluated through thermal balance equation of vehicle compartment. The procedure of this evaluation is verified by showing test result. In vehicle test, the remote controller, a real-time experimental system for climate control, is used. The software of remote controller is programmed by Visual C++ operating on WIN95 and the hardware is similar to a real electronic control unit of HVAC. Remote controller predicts control efficiency of HVAC system. The goal of this paper is to get the standard model of development procedure. It would contribute cost reduction and rapid development of climate control algorithm for a passenger car.

This model is developed based on the concept of Hiroyasu's multizone combustion model. It takes nozzle injection (spray) parameters, induction swirl, air and fuel composition into consideration. The models of zone velocity, air entrainment rate, fuel droplet evaporation rate, mixture combustion rate are upgraded according to the latest papers. Various parameters, such as cylinder pressure, heat release rate, NOx and soot emissions, etc. are simulated. The simulated zone velocity and spray tip penetration are compared with those computed by Hiroyasu. The simulation results show good agreement with the experimental data.

Recent advanced technologies in diesel engine FIE(Fuel Injection Equipment) allow high pressure and multiple injection to be used to reduce particulate emissions without significant penalty in NOx emission. It is also well known that diesel engine particulate matter(PM) and NOx emissions can be reduced by the exact injection rate control according to engine conditions. This study was conducted based on such engine conditions as engine speed, load, swirl ratio and solenoid pulse timing and duration. The fast solenoid valve was installed between the connecting part of nozzle and fuel line. The ball valve driven by solenoid is open after the controller generates pulse and it spills the high pressure fuel in the high pressure nozzle chamber. Fuel line pressure, injection rate, cylinder pressure and exhaust emissions were measured with the variation of control method(pulse timing and pulse duration period).