In today's modern world the internal combustion engine has a predominant role in stationary low power generation and a virtual monopoly in mobile application. It has been seen that one of the main pollutant from the exhaust is NOx. In this work we are discussing one of the method to reduce this emission by introducing water into the combustion chamber through the inlet manifold during suction stroke.
The experimental part of the work involves the fabrication of a separate water injection system consisting of pump and an injector being driven by the engine itself. Water is introduced in the inlet manifold and different performance tests like heat balance, load test and emission measurements are conducted on a Kirloskar Engine. The effect of water on different factors like Brake Thermal Efficiency, Fuel Consumption, NOx, CO, Unburned Hydrocarbon and CO2 at different load conditions is studied.
From the graphs of emission readings for different water fuel ratio (W / F) ratio it has been found that with the increase in W / F ratio there is a slight decrease in the brake thermal efficiency, a constant decrease in NOx, a negligible change in CO and a slight increase in the HC.
From the different graphs a range of optimum water fuel ratio is chosen at which it is seen that the decrease in the NOx emissions doesn't cause too much decrease in the engine efficiency.