experimental investigation of the effect of compression ratio in a direct injection diesel engine fueled with spirulina algae biodiesel

Experiments have been carried out on a single cylinder, four stroke, and variable compression ratio diesel engine to investigate the effect of compression ratio on its performance, combustion and emission parameters, when it is fuelled with spirulina of 20%, 40%, 60% and 80% blend with standard diesel. the parameters that were measured comprised of performance parameters such as brake power (bp), brake thermal efficiency (bthe), brake specific fuel consumption (bsfc), mechanical efficiency, along with combustion parameters such as cylinder pressure and net heat release rate (hrr). the exhaust gas emission included carbon monoxide (co), carbon dioxide (co2), nitrogen oxides (nox) and hydrocarbon (hc). the results obtained for spirulina at compression ratios (cr) of 15, 16 and 17.5, at different loads have been compared and analyzed to that of standard diesel. after analyzing the data, it is evident that while fuelling the engine with spirulina biodiesel, there is a clear decrease in the emission of carbon monoxide, nitrogen oxides and hydrocarbons. and the performance characteristics of the engine remain unaltered. the optimum engine performance was found at higher compression ratio.