Library Subscription: Guest
International Heat Transfer Conference 13
Graham de Vahl Davis (open in a new tab) School of Mechanical and Manufacturing Engineering, University of New South Wales, Kensington, NSW, Australia
Eddie Leonardi (open in a new tab) Computational Fluid Dynamics Research Laboratory, School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, Australia 2052

ISSN Online: 2377-424X

ISBN CD: 1-56700-226-9

ISBN Online: 1-56700-225-0

LOCAL HEAT TRANSFER MEASUREMENTS AND NUMERICAL ANALYSIS IN THE COOLING PASSAGE OF THE VENTILATED DISC BRAKE WITH HELICALLY FLUTED SURFACES

page 12
DOI: 10.1615/IHTC13.p22.400
Get accessGet access

ABSTRACT

Local Nusselt numbers in the cooling flow passage of the automobile disc brake with helically fluted surfaces are presented. The flat surface in the flow passage is modified to the helically fluted surface for the purpose of enhancing the heat transfer rate, thereby reducing the thermal stress and deformation in the disc brake. Thermochromic liquid crystals and shroud-transient technique are used to measure spatially-resolved surface temperature distributions, which are used to deduce local Nusselt numbers. The Reynolds number Re ranges from 30,000 to 70,000, the helix angle θ is fixed at 45° and the dimensionless streamwise distance z/d ranges from 1.5 to 4.5. The results show that in general, local Nusselt numbers monotonically decrease with a distance away from both windward and leeward crests of the helical flute and reach a minimum value near its valley for all Re's and z/d's tested. The local Nusselt numbers on the helically fluted grooves are maximum 51.6 to 93.7% higher than values measured on the flat surface. The heat transfer enhancement magnitudes become more pronounced with smaller Re and z/d. The largest enhancement occurs at the windward side of the helical flute at z/d = 1.5 and Re=30,000. It is also found that at Re=30,000 the average Nusselt numbers on the helically fluted surface are maximum 37% higher than those on the flat surface. The numerical results show that 10 cycles braking, the temperatures with helically fluted surface are maximum 44.3%, 36.8%, 36.6% lower than those with the flat surface in the inlet, the center, the outlet, respectively.

Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections Prices and Subscription Policies Begell House Contact Us Language English 中文 Русский Português German French Spain