Effects of combustion efficiency on a Dual cycle

Osman Azmi Ozsoysal*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

25 Citations (Scopus)


This paper studies a Dual cycle model containing irreversibilities coming exclusively from expansion and compression processes. It is assumed that any fraction of the fuel's chemical energy can not fully released inside the engine because of the incomplete combustion. Utilizing the combustion efficiency is found to be more useful to realize the cycle feasibility. Amount of the released energy from fuel into the cylinder restricts the compression ratio. It is presented how the upper limit of compression ratio is evaluated by means of using some constraints for realizing a Dual cycle. Valid ranges of the constraints given in literature seriously affect the feasibility of cycle. Developed mathematical model leads to a qualitative understanding of how engine loss can be reduced. Thermal efficiency-work curves cannot have a closed loop shape because there is a close relationship between the fuel energy, air-fuel mass ratio, combustion efficiency, maximum cycle temperature and the heat losses into the cylinder wall. If these are all omitted, while heat losses are determined independently without establishing any relationship between the released fuel energy, the thermal efficiency versus work curves will just be able to have a closed loop shape. This is the original perspective and contribution of paper.

Original languageEnglish
Pages (from-to)2400-2406
Number of pages7
JournalEnergy Conversion and Management
Issue number9
Publication statusPublished - Sept 2009


  • Air-fuel ratio
  • Combustion efficiency
  • Fuel conversion efficiency
  • Irreversible Dual cycle
  • Waste energy


Dive into the research topics of 'Effects of combustion efficiency on a Dual cycle'. Together they form a unique fingerprint.

Cite this