Volume 23, Issue 60, July - December, 2026

Influence of ignition timing on heat transfer rate between the burned gases and the gas-side cylinder wall of a spark ignition engine

Mohammad Al-Hasan^♦

Department of Mechanical Engineering, Faculty of Engineering Technology, Al-Balqa' Applied University, Al-Salt, Jordan

^♦Corresponding Author
Mohammad Ibrahim Al-Hasan, Department of Mechanical Engineering, Faculty of Engineering Technology, Al-Balqa' Applied University, Al-Salt, Jordan

ABSTRACT

Heat transfer is one of the most important issues that must be considered when studying internal combustion engines (ICEe), due to its influence on engine operating parameters such as temperature and pressure inside the cylinder, engine brake thermal efficiency, fuel consumption, and emissions. The objective of this study was to investigate the effect of engine Ignition Timing (IT) on the heat transfer rate between the gases burned in the cylinders, and the cylinder walls of a spark ignition engine (SI). For this purpose, the engines design geometric parameters were utilized to calculate the instantaneous cylinder volume(Vg), in-cylinder pressure (Pg) and temperature ( Tg), gas-side cylinder wall temperature, and the convective heat transfer coefficient (hg) for different ignition timing of 30°, 25°, 20°,15°, and 10° before Top Dead Center (bTDC). The results show that, when the combustion process starts early during the compression stroke i.e. at an ignition timing of 30° bTDC, most of the air-fuel mixture burns before the piston reaches the TDC. Consequently the Pg , Tg ,hg and the heat transfer rate, Q(θ), reaches their maximum value at 30⁰ bTDC. However, as the ignition timing decreases up to 15° and 10° bTDC the values of the stated above parameters increase and reaches their maximum values after Top Dead Center (aTDC). Furthermore, the obtained results were compared with finding from other researcher’s, indicating that the present results are largely consistent with previously published data. Additionally, cylinder wall temperature distribution results obtained via FlexPDE software conformed to those from the analytical method, as demonstrated by the coefficient of determination, R², of 0.934, 0.926, and 0.894 for ignition timing of 10⁰, 20⁰, and 30⁰ bTDC, respectively. Thus, taking into account the aforementioned results, the best ignition timing for the engine used in this study is found to be 10° CA bTDC based on the obtained maximum values of 7.5 (MPa), 3188 (K), 576 (W⁄m2 .K), 625 (K) and 8316 (W), for Pg, Tg, hg, Tw and Q(θ), respectively.

Keywords: heat transfer, ignition timing, cylinder pressure and temperature and FlexPDE

Indian Journal of Engineering, 2026, 23(60), e13ije1731

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DOI: https://doi.org/10.54905/disssi.v23i60.e13ije1731

Published: 30 September 2026