Performance of diesel engine run on hydrogen as supplementary fuel

A study was conducted to assess the percent diesel replacement by hydrogen on a Kirloskar make 10 hp four stroke compression ignition engine using hydrogen as supplementary fuel. It was found that up to 60% of diesel could be replaced by hydrogen at 60% of rated brake load, beyond which excessive knocking started. At 80% of rated brake load, only 30% of diesel could be replaced by hydrogen beyond which excessive knocking started. At rated load, only 10% of diesel could be replaced by hydrogen beyond which the engine gave excessive black smoke. This might be due to incomplete burning of diesel and hydrogen due to shortage of air supply. At 60% of rated brake load, the flow rate of hydrogen was 12.82,21.72,29.10,38.71,47.50 and 76.58 lpm when 10,20,30, 40,50 and 60 per cent diesel was replaced by hydrogen, respectively. At 80% of rated brake load, the flow rate of hydrogen was 15.09, 23.83 and 36.74 lpm when 10, 20 and 30 per cent diesel was replaced, respectively. At 100% and 110% of rated brake load, the flow rate of hydrogen was 16.53 and 19 lpm respectively at 90% diesel. From the long duration test, it was found that at 60% of rated brake load, replacement of diesel by 40% hydrogen was smoother and the power of the engine did not fall even after two hours of running. Thus, the diesel engine can be run on 60% diesel + 40% hydrogen at 60% of rated brake load without any detrimental effects.