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An evaporator which is one of important components of the automobile air conditioning system has been developed on the view point of increasing heat transfer coefficient and decreasing fluid pressure loss. To employ new configuration of refrigerant side heat transfer tube surface could improve heat transfer coefficient by 2.6 times of smooth surface heat transfer coefficient. A distribution adjustment pipe and optimized arrangement of heat transfer tubes were applied to achieve uniform refrigerant flow distribution. We tried to minimize the increase of refrigerant side pressure caused by employing turbulizers inside the heat transfer tubes. We studied on thermo-fluidic behavior experimentally and developed new high performance evaporator.

Lean combustion in spark-ignition engines has long been recognised as a means of reducing both exhaust emissions and fuel consumption. However, problems associated with cycle-by-cycle variations in flame initiation and development limit the range of lean-burn operation. An experimental investigation was undertaken in order to quantify the effects of spark energy released and initial flame kernel growth on the cyclic variability of IMEP and crank angle at which 5% mass fraction was burned in a Honda VTEC-E, stratified-charge, pentroof-type, single-cylinder, optically accessed, spark-ignition engine. Simultaneous CCD images of the flame at the spark plug were acquired from two orthogonal views (one through the piston crown and one through the pentroof) on a cycle-by-cycle basis during the first 40 crank angle degrees after ignition timing, for isooctane port injection at an air to fuel ratio of 22, engine speed of 1500 RPM, 30% volumetric efficiency and 40° crank angle spark advance.