Validation of Gasoline Surrogates Through Thermodynamic Analysis of Spark-Ignition Engine

Abstract

The investigation aims to evaluate the impacts of commercial gasoline and gasoline surrogates on energy and exergy efficiencies in a spark-ignition (SI) engine. In this investigation, a new approach for formulating next-generation gasoline surrogates is investigated through testing these surrogates in a multi-cylinder SI engine. Energy and exergy analyses were carried out using the primary reference fuel-methylcyclohexane (PRF-MCH) blend (82.88% iso-octane + 9.16% n-heptane + 7.96% methylcyclohexane), primary reference fuel with 1,2,4-trimethylbenzene (PRF-1,2,4-TMB) blends (76% iso-octane + 9% n-heptane + 15% 1,2,4-trimethylbenzene and 61% iso-octane + 9% n-heptane + 30% 1,2,4-trimethylbenzene), and commercially available gasoline (gasoline) in an SI engine. The engine investigation results show that the PRF-MCH blend is a promising surrogate to reproduce the gasoline fuel engine characteristics such as combustion and emission characteristics of gasoline fuel. The detailed experiments were executed at the SI-engine speed conditions of 1500 rpm and 2500 rpm. It is found that PRF-MCH blend energy-exergy efficiencies are comparable to commercially available gasoline. It can also be concluded that engine testing in terms of energy-exergy analyses for proposed gasoline surrogates provides a qualitative and quantitative understanding of combustion behavior, emission characteristics, assessment of the effectiveness, and useful work potential gasoline surrogates.