Engine management for air conditioning systems utilizing exhaust gas heat

摘要

Vehicle air conditioning systems utilizing engine exhaust gas heat could be a promising technology. However, the exhaust gas heat and temperature can be insufficient for the systems at light load conditions such as idle and slowdown. This paper proposes a combination of wide range retardation of spark timing and throttle valve opening for increasing exhaust gas heat at light load conditions. The results by evaluation with Japanese 10-15 driving mode shows this technique increases the exhaust gas heat at light load conditions with smaller deterioration in fuel consumption than elevating the engine speed. Characteristics of efficiency factors with the technique were also analyzed in detail.