Peak pressure analysis for modified mild steel DI diesel engines with copper-coated pistons and engine heads under dual fuel injection mode

Abstract

The current study assesses the impact of ethanol injection using a secondary injection system on thermal efficiency and engine combustion pressure. To enable observations to be made at each operating point in a progressive increasing or decreasing order, all sets of operating conditions chosen for the experiment are structured in a sequence. The engine's dual fuel mode allows it to run on various concentrations of ethanol using a separate injection system. In this experiment, the engine ran on various ethanol blends of 10%, 20%, and 30% in addition to the basic gasoline. An increase in the peak pressure with load for all fuel combinations and a decrease with dilution except at 50% load is observed in the experiments. In addition, both the oils in dual fuel mode give maximum peak cylinder pressure after the TDC, which is encouraging. The highest peak pressure of 61.21 bar at 363.53°CA, obtained with biodiesel and ethanol is less than that of neat diesel as 65.95 bar at 364.85°CA, creating no danger to the engine structure which is made of Mild steel with a copper-coated piston and cylinder head arrangement. With the increase in ethanol substitution, an improvement in efficiency is recorded for biodiesel at all loads. In addition, for the same ethanol content, biodiesel gives higher BTE than diesel under similar loading conditions. It is observed that ethanol addition has an almost similar effect on both diesel and biodiesel at all loads.