Performance and emission analysis of hydrogen fueled compression ignition engine with variable water injection timing

The effect of variable water injection timing on performance and emission characteristics of hydrogen fueled compression ignition (HFCI) engine has been investigated and the results are presented in this paper. In this study, water is injected from 20 degrees BTDC to 20 degrees ATDC with injection duration of 20 degrees CA and 40 degrees CA. Hydrogen is injected at the intake port with fixed injection timing from 0 degrees CA to 40 degrees CA and constant flow rate of 5 LPM. The results indicate that water injection timing of 20 degrees ATDC and duration of 20 degrees CA has shown better engine performance due to increased gross indicated work and indicated thermal efficiency. It has also demonstrated that the lowest NOx concentrations for engine speed greater than 2500 RPM and lower EGT throughout entire speed range. Water injection timing of 20 degrees BTDC and duration of 40 degrees CA has shown the highest heat release rate and the longest ignition delay. Water injection timing of 0 degrees CA and duration of 40 degrees CA indicated that the highest O-2 and SO2 emissions throughout entire speed range. It is observed that water injection technique appears to be promising method to enhance the performance and emissions quality of HFCI engine effectively. (C) 2012 Elsevier Ltd. All rights reserved.