Influence of Nozzle Opening Pressure, Fuel Injection Timing and Compression Ratio on the Performance of Compression Ignition Engine Fueled with Biodiesel-Diesel-Butanol Blends

Biodiesel from vegetable waste can be utilized as fuel for compression ignition engine. This experimental study used biodiesel extracted from the cauliflower outer leaves and butanol from vegetable waste as property enhancer to fuel the diesel engine. This study consists of two stages: Solubility and properties test of various proportions of diesel biodiesel butanol blends to obtain an optimal fuel blend that possesses closer properties to that of diesel; followed by testing the optimal blend in a modified engine for nozzle opening pressure (180, 190, 200 and 210 bar), fuel injection timing (23, 26, 29 and 32⁰ before top dead centre) and compression ratio (16: 1, 17.5:1, 19:1 and 20.5:1). The optimal level of these parameters was attained using L16 orthogonal array and Taguchi method. Test results showed that the blend containing 40% biodiesel 20% diesel and 40% butanol can be used as fuel for diesel engine. The diesel engine was operated under 210 bar of nozzle opening pressure, 26⁰before top dead center of fuel injection timing and 19:1 of compression ratio. This optimal blend produced closer brake thermal efficiency, in-cylinder peak pressure, peak heat release rate, ignition delay, and combustion duration which were found to be similar compared to that of diesel (above 40% of rated power). The emissions produced by this blend were found lower compared to that of diesel operated at higher brake power condition (above 50% of rated power). This study enables to utilize the waste vegetables and renewable resources to fuel diesel engine and replacing the diesel to a certain extent.