Heat release rate and engine vibration correlation to investigate combustion propensity of an IDI engine run with biodiesel (MME) and methanol additive as an alternative to diesel fuel

Abstract

An experimental investigation was carried out to study the combustion pressure, heat release rate and cylinder vibration of an Indirect Diesel Injection (IDI) engine fueled with Mahua methyl ester (MME) along with methanol additive blends. A four-stroke single-cylinder IDI engine was used for this investigation. A comparative study was conducted using diesel, MME and methanol additive blends of MME on an IDI engine. Substantial improvement can be observed from the net heat and cumulative heat release rate plots in which 3% additive blend reached the performance of diesel fuel and the corresponding cylinder vibration plots indicated smoother combustion for the above blend. This envisages that above blend reduces the heterogeneity of combustion to greater extent and ensures judicious sharing of combustion within the chambers leading to better torque conversion and lesser possibility of leakage of biodiesel into the crank case at higher loads of the engine. Five additive blends of methanol in MME were tested, the blending ratios of 1/99%, 2/98%, 3/97%, 4/96% and 5/95% additive methanol is added to MME, and five discrete part load conditions viz. No Load, 0.77 kW, 1.54 kW, 2.31 kW and 2.70 kW loads without gear box and clutch assembly ensuring stable engine operation.