Analyzing Factors Affecting Gross Indicated Efficiency When Inlet Temperature Is Changed

Research output: Contribution to journalArticle


Observations from engine experiments indicates that the gross indicated efficiency (GIE) increases when the inlet temperature (Tinlet) is lowered. The change in Tinlet affects several important factors, such as the heat release profile (affecting heat and exhaust losses), working fluid properties, combustion efficiency and heat transfer losses. These factors all individually contributes to the resulting change in GIE. However, due to their strong dependency to temperature it is not possible to quantify the contribution from each of these parameters individually. Therefore, a simulation model in GT-power has been created and calibrated to the performed engine experiments. With simulations the temperature dependency can be separated and it becomes possible to evaluate the contribution to GIE from each factor individually. The simulation results indicate that the specific heats of the working medium are the largest contributor. Heat transfer and combustion efficiency are also important factors but are not as significant as the effect from specific heats.


External organisations
  • Volvo Group Trucks Technology
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Energy Engineering
Original languageEnglish
Article number2018-01-1780
Number of pages19
JournalSAE Technical Papers
Publication statusPublished - 2018 Sep 10
Publication categoryResearch

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Nhut Lam, 2019, Energy Sciences, Lund University. 262 p.

Research output: ThesisDoctoral Thesis (compilation)

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Related projects

Per Tunestål, Nhut Lam, Kenan Muric & Bengt Johansson

Swedish Energy Agency

2013/01/01 → …

Project: ResearchCollaboration with industry

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