Wankel motorunda direkt püskürtmenin deneysel analizi

Wankel engine is one of internal engine types which does not have reciprocating part and transfers the combustion energy through the rotor to eccentric shaft directly. Due to this it has lower vibration than conventional reciprocating engines. Low weight and high power density are the another advantages of this engine. Of course beside any advantage there are always some disadvantages. High fuel consumption and HC emissions are the most important disadvantages of this engine. Although leakage is one of the important problems that increase the fuel consumption and HC emissions; late combustion in the trailing area of combustion chamber is another problem in this engine that contributes to increasing fuel consumption and HC Emissions. In Wankel engine, during the expansion stroke, the trailing side of the combustion chamber is always smaller than the leading side of it and this quenches fire flame and the fuel existent in here stays unburned and due to this fuel consumption and HC emissions increases. If it is possible to control the mixture in the combustion chamber, and make the mixture leaner in this area, it is possible to tackle this problem. Direct injection system and make stratified charge is the only way to do this. In this working, it is tried to control the mixture formation in the Wankel engine by using the direct injection system. Firstly, by searching in the literature, a proper place for injection is selected. Secondly, two injector having the criteria for this aim have been selected. Then, these injectors have been tested for in their flow rates, spray geometries, injection delays and effect of changing the voltage in the flow rate and injection delay. After testing the injectors, some simulations for the injection appearances have been done to see what will happen in the experiments and estimate the injection times and durations without having collision with rotor. The experiments were done in different engine speed, load and excess air ratios and the results were investigated. The best start of injection points selected and effect of changing this start points were examined. The results show that the spray coming out from PFI injectors could not be atomized in the intake side of the engine and collision with rotor is the only way to atomize and evaporate the fuel. By the way, the fuel consumption and HC emissions increased by using this method. So, to have a good atomization it is necessary to use direct injection injectors with high fuel pressures.