In the present work an experimental investigation was conducted to examine the effect of combustion of biogas on the performance of hybrid biogas-diesel dual fuel engine converted from a diesel engine. With a retrofitted control system, the hybrid engine can operate either on diesel or on biogas with different CH4 concentrations. Effects of biogas composition, equivalence ratio, engine speed and pilot injection on engine performance were taken into consideration. The tests were carried out on the AVL engine test bed with APA204 dynamometer. The results show that peak of cylinder pressure and indicated engine cycle work decrease as decreasing CH4 concentration in biogas or/and as increasing engine speed. The maximum indicated engine cycle work was obtained with slightly rich mixture. With rich biogas, the hybrid biogas-diesel dual fuel engine ignited by pilot injection of 10% of rated injection can develop output power equivalent to rated power of diesel mode. But with raw biogas (CH4 concentration in biogas under 70%), power of dual fuel mode is lower than rated power of diesel mode thus an increase of pilot injection is needed to meet requirements of external load. In case of shortfall of biogas supply, the engine can be switched automatically to diesel operation. The new concept of hybrid biogas-diesel dual fuel engine is very useful in rural area. It can operate and save fossil fuel at any biogas supply conditions.
Primary Language | English |
---|---|
Journal Section | Articles |
Authors | |
Publication Date | December 1, 2015 |
Published in Issue | Year 2015 Volume: 5 Issue: 4 |