Mathematical correlations for variation in heat release rate of a diesel engine fuelled with n-octanol blends

Authors : Mert Gülüm

Pages : 1452-1480

Doi:10.28948/ngumuh.1320921

View : 120 | Download : 112

Publication Date : 2023-10-15

Article Type : Research Paper

Abstract :The current literature reports a few papers regarding the prediction of heat release rate of a diesel engine fuelled with n-octanol blends using numerical methods. To address this gap, the main objective of the presented study is to derive correlations for estimating the variation in heat release rate of a diesel engine fuelled with diesel fuel and diesel fuel-biodiesel-n-octanol blends. For this purpose, three different ternary blends were prepared by varying the n-octanol concentration to 6% (OCT6), 8% (OCT8), and 10% (OCT10) by volume. The estimation of heat release rate was accomplished using the least-squares regression (sine, piecewise, and rational equations) and the function approximation (Padé approximation) methods. The ignition delay and peak heat release rate increased by 3.8462%, 5.9501% for OCT6; 7.6923%, 3.7125% for OCT8; and 8.9744%, 3.0755% for OCT10, respectively, compared to diesel fuel. The peak cylinder pressure of OCT6 and OCT8 was observed to be higher by 2.4378% and 1.3982%, respectively, whereas that of OCT10 was found to be lower by 1.9458%, compared to diesel fuel. Compared to the others, the suggested rational equation qualitatively and quantitatively achieved the best correlation with all experimental heat release rate data measured by both the author and some other authors.
Keywords : n Oktanol, Isı yayılımı oranı, Sinüs denklemi, Padé yaklaşımı, Parçalı denklem