Title: A new method for optimum selection of two-stage turbocharger for heavy duty diesel engine
Authors: Sepehr Sanaye; Shahram Sedghi Ghadikolaee; Seyed Ahmad Akbari Moghadam
Addresses: School of Mechanical Engineering, Energy Systems Improvement Laboratory, Iran University of Science and Technology, Narmak, Tehran 16844, Iran ' School of Mechanical Engineering, Energy Systems Improvement Laboratory, Iran University of Science and Technology, Narmak, Tehran 16844, Iran ' School of Mechanical Engineering, Energy Systems Improvement Laboratory, Iran University of Science and Technology, Narmak, Tehran 16844, Iran
Abstract: For selecting an optimum two-stage turbocharger, a new approach is proposed here which uses thermodynamic and turbomachinery modelling, genetic algorithm (GA) optimisation technique and GT-Power software. In the primary step, the optimum high pressure (HP) and low pressure (LP) turbochargers were selected by minimising an objective function (the sum of losses in compressors and turbines). Design parameters in the optimisation procedure were geometrical and aerodynamic parameters of compressors and turbines. The final step consisted of adding control valves to achieve the optimal engine performance at various engine speeds. In this step, brake specific fuel consumption (bsfc) was the objective function which was minimised. Based on the results of optimum value of design parameters in the final step, HP and LP turbochargers were reselected with 9.2% increase in brake power and 2.4% decrease in bsfc as the mean values in comparison with a single-stage turbocharger for a specific studied engine.
Keywords: two-stage turbocharging; control valve position; genetic algorithms; optimisation; heavy duty diesel engines; vehicle turbocharging; turbocharger selection; thermodynamic modelling; turbomachinery modelling; thermodynamics; engine performance; engine speeds; brake specific fuel consumption; geometrical parameters; aerodynamic parameters; compressors; turbines.
DOI: 10.1504/IJHVS.2015.070416
International Journal of Heavy Vehicle Systems, 2015 Vol.22 No.1, pp.42 - 72
Received: 29 Aug 2014
Accepted: 19 Dec 2014
Published online: 05 Jul 2015 *