Experimental investigation of performance and emission characteristics in a variable compression ratio diesel engine using partly cold exhaust gas recirculation (EGR) method

In diesel engines, NOx formation is a highly temperature dependent phenomenon and takes place when the temperature in the combustion chamber exceeds 2000 K. Therefore in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control. One simple way of reducing the NOx emission of a diesel engine is exhaust gas recirculation (EGR) method. A heat exchanger arrangement is provided for obtaining different EGR methods. The performance parameters were studied with and without exhaust gas recirculation of different methods with 2 litre per minute to 8 litre per minute of EGR. The recycled exhaust gas lowers the oxygen concentration in the combustion chamber and increases the temperature of intake charge which lowers the flame temperature and leads to lower NOx formation. Compression ratio is one of the important parameters which influence the performance of the Direct Injection Diesel engine. The main aim of this work is to carry out experimental investigation to establish the performance and emission of variable compression ratio diesel engine using different quantities of partly cold EGR on exhaust gas temperatures. The Effect of EGR is which in turn reduces the NOx and increases the performance characteristics at the compression ratio of 17:1.