Tuncer, ErdalDogan, BattalSandalci, TarkanErol, Dervis2025-01-212025-01-2120221742-82971742-8300https://doi.org/10.1504/IJEX.2022.125523https://hdl.handle.net/20.500.12587/24690In this study, performance and exhaust emissions were examined experimentally at different engine loads (25%, 50%, and 75%) at a constant speed of 1,500 rpm using pure diesel before modifications and pure natural gas (NG100) after modifications. Furthermore, experimental studies were conducted under 2 normal-1 skipped cycle (2N1S) and 3 normal-1 skipped cycle (3N1S) conditions using pure natural gas as a fuel in a converted spark-ignition engine. In the present study, energy and exergy analyses were performed using the performance and exhaust emission values obtained from experiments. As a result of the energy analysis, effective thermal efficiency values of 39.46% and 34.37% were found in diesel and natural gas fuels, respectively, at an engine load of 75% without cycle skipping. It was observed that the effective thermal efficiency value reached the maximum value of 35.99% in case of cycle skipping in natural gas and at an engine load of 50%.eninfo:eu-repo/semantics/closedAccessnatural gas; skipped cycle; pollutant emissions; energy analysis; exergy analysisArticle39217319410.1504/IJEX.2022.1255232-s2.0-85140954466Q3WOS:000853402700004Q4