Indexed by: Journal Papers

Date of Publication: 2014-10-02

Journal: NANOSCALE AND MICROSCALE THERMOPHYSICAL ENGINEERING

Included Journals: SCIE、EI

Document Type: J

Volume: 18

Issue: 4

Page Number: 329-353

ISSN No.: 1556-7265

Key Words: wall function; nanofluids; piston; impingement cooling; multiphase model; turbulence model

Abstract: Nanofluids exhibit interesting heat transfer enhancement capabilities that may render them good candidates for use in industrial applications. They can be used as a cooling medium to spray onto the bottom of a piston to reduce the overall heat load during the operation of an engine. However, the flow and temperature fields in an impinging jet of nanofluid are rather complex in the multiphase turbulent state. In order to accurately describe the flow and heat transfer processes in an impinging jet, the current article explores several different turbulence models and wall functions, discusses the velocity and temperature fields predicted by the single-phase model and various multiphase models, and analyzes the influence of nanoparticles on the base fluid. On this basis, the effects of physical properties, concentration, Reynolds number, and geometrical configuration on the process of impingement cooling with nanofluids are investigated. The results may provide a reliable reference for the transient spray cooling of pistons with nanofluids.