Universiti Teknologi Malaysia Institutional Repository

Variable geometry mixed flow turbine for turbochargers: an experimental study

Rajoo, Srithar and Botas, Ricardo Martinez (2008) Variable geometry mixed flow turbine for turbochargers: an experimental study. International Journal of Fluid Machinery and Systems, 1 (1). pp. 155-168. ISSN 1882-9554 online

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Official URL: http://www.jstage.jst.go.jp/browse/ijfms/_vols

Abstract

This paper investigates a variable geometry (VG) mixed flow turbine with a novel, purposely designed pivoting nozzle vane ring. The nozzle vane ring was matched to the 3-dimensional aspect of the mixed flow rotor leading edge with lean stacking. It was found that for a nozzle vane ring in a volute, the vane surface pressure is highly affected by the flow in the volute rather than the adjacent vane surface interactions, especially at closer nozzle positions. The performance of the VG mixed flow turbine has been evaluated experimentally in steady and unsteady flow conditions. The VG mixed flow turbine shows higher peak efficiency and swallowing capacity at various vane angle settings compared to an equivalent nozzleless turbine. Comparison with an equivalent straight vane arrangement shows a higher swallowing capacity but similar efficiencies. The VG turbine unsteady performance was found to deviate substantially from the quasi-steady assumption compared to a nozzleless turbine. This is more evident in the higher vane angle settings (smaller nozzle passage), where there are high possibility of choking during a pulse cycle. The presented steady and unsteady results are expected to be beneficial in the design of variable geometry turbochargers, especially the ones with a mixed flow turbine

Item Type:Article
Uncontrolled Keywords:variable geometry turbocharger, mixed flow turbine, steady flow and pulsating flow
Subjects:T Technology > TJ Mechanical engineering and machinery
Divisions:Mechanical Engineering
ID Code:8477
Deposited By: Norshiela Buyamin
Deposited On:05 May 2009 00:31
Last Modified:02 Jun 2010 01:55

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