Visual Journal of Technical and Vocational Education

Visual Journal of Technical and Vocational Education

Using the response surface methodology to analyze the effect of fuel injection pressure on lambda, ignition advance and exhaust emissions in the SI engines

Document Type : Original Article

Authors
1 Department of Agriculture Engineering, National University of Skills(NUS), Tehran, Iran
2 Department of Mechanical Engineering, National University of Skills(NUS), Tehran, Iran
3 Department of Physical Education and Sport Sciences, Dr. Shariati Faculty of Physical Education, National University of skills(NUS),Tehran,Iran=
10.48301/vjtve.2026.516331.1110
Abstract
In gasoline engines, the fuel delivery system is one of the most precise and critical components. The design of fuel pathways, pumps, filters, and related features directly impacts fuel pressure a key parameter for combustion performance. In this study, in order to evaluate the combustion parameters and exhaust emissions of a gasoline engine, the effect of fuel injection pressure on lambda (ratio between the actual air-fuel ratio and the stoichiometric air-fuel ratio), ignition advance and exhaust emissions of the engine has been investigated using the response surface method. The test results indicated that the amount of Lambda, ignition advance, CO and HC increased with decreasing the fuel injection pressure. The highest values of Lambda, ignition advance and CO at 5000 rpm with fuel injection pressure of 2.4 bar was measured as 1.044, 37° and 0.88%, respectively. The highest value of CO2 gas was recorded at 1000 rpm with fuel injection pressure of 3.5 bar at 14.8%. The lowest amount of HC emission was reported at 5000 rpm engine and with fuel injection pressure of 3.5 bar as 86 ppm. The results of this study showed that fuel pressure in a gasoline engine is an effective parameter in engine performance and emissions. The study showed that proper design and maintenance of the fuel system maintain optimal fuel pressure, improve engine performance, and reduce exhaust emissions. This plays a key role in reducing air pollution in metropolitan areas
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Articles in Press, Accepted Manuscript
Available Online from 20 April 2026

  • Receive Date 03 June 2025
  • Revise Date 30 November 2025
  • Accept Date 20 April 2026