Performance optimization of preheated palm oil-diesel blends using integrated response surface methodology and analysis of variance

Abstract

Performance enhancement is one of the major research topics where researchers are focusing on various biofuels, blending ratios and optimization. Whereas previous researches have not optimized the performance of preheated palm oil (PHPO) with diesel, this research optimizes the performance of PHPO with diesel at 90°C. Investigations were made with various volume fractions i.e. 0.05, 0.1, 0.15 and 0.2 of PHPO in diesel to form O5, O10, O15 and O20, respectively. Regression modelling employing RSM is adopted to find the behavioural variation of input parameters on the performance of PHPO. Central composite rotatable designs with 31 experimental runs were conducted. Blending ratio (BR), compression ratio (CR), load and water flow were used as input parameters. Theoretical modelling was carried out to correlate the control parameters with performance parameters like brake thermal efficiency (BTE), specific fuel consumption (SFC) and exhaust gas temperature (EGT). There was an increase in BTE, decrease in SFC and EGT on increasing the load and CR. A maximum BTE of 25% was achieved by varying the CR and load from 18.5 to 20 and 7–10 kg, respectively. Regarding SFC and EGT, a 10% decrement in SFC and a 3% decrement in EGT was achieved by varying the CR from 16 to 20. All the tests with higher CR gave lower emissions for all PHPO blends. Water flow rate does not have any influence on performance. In particular, O10 blend gave better performance at maximum load with a CR 18 and was found to be a potential choice for diesel engine.