0
Research Papers: Porous Media

Thermofluidic Characteristics of a Porous Ventilated Brake Disk

[+] Author and Article Information
H. B. Yan

School of Energy and Power Engineering,
Xi'an Jiaotong University,
Xi'an 710049, China
e-mail: hongbinyanhb@163.com

T. Mew

School of Mechanical Engineering,
University of the Witwatersrand,
Johannesburg 2050, South Africa
e-mail: timdmew@gmail.com

M.-G. Lee

Department of Mechanical Systems Engineering,
Chonnam National University,
Gwangju 500-757, South Korea
e-mail: kkameoe@naver.com

K.-J. Kang

Department of Mechanical Systems Engineering,
Chonnam National University,
Gwangju 500-757, South Korea
e-mail: kjkang@chonnam.ac.kr

T. J. Lu

State Key Laboratory
for Mechanical Structure Strength and Vibration,
School of Aerospace,
Xi'an Jiaotong University,
Xi'an 710049, China
e-mail: tjlu@mail.xjtu.edu.cn

F. W. Kienhöfer

School of Mechanical Engineering,
University of the Witwatersrand,
Johannesburg 2050, South Africa
e-mail: frank.kienhofer@wits.ac.za

T. Kim

School of Mechanical Engineering,
University of the Witwatersrand,
Johannesburg 2050, South Africa
e-mail: tong.kim@wits.ac.za

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received October 1, 2013; final manuscript received October 15, 2014; published online November 18, 2014. Assoc. Editor: Wei Tong.

J. Heat Transfer 137(2), 022601 (Feb 01, 2015) (11 pages) Paper No: HT-13-1523; doi: 10.1115/1.4028864 History: Received October 01, 2013; Revised October 15, 2014; Online November 18, 2014

We introduce a new class of ventilated brake disk which incorporates an open cellular core: wire-woven bulk diamond (WBD). Transient and steady-state thermofluidic characteristics are presented. As reference, a commercially available pin-finned brake disk is also considered. At a braking power of 1.9 kW, representative of a medium sized truck descending a 2% gradient at a vehicle speed of 40 km/h (i.e., 200 rpm), the WBD cored brake disk reduces the overall brake disk temperature by up to 24% compared to the pin-finned brake disk. Results also reveal that in typical operating ranges (up to 1000 rpm), the WBD core provides up to 36% higher steady-state overall cooling capacity over that obtainable by the pin-finned core. In addition, the three-dimensional morphology of the WBD core gives rise to a tangentially and radially more uniform temperature distribution. Although the WBD core causes a higher pressure drop, this is balanced by the benefit of a stronger suction of cooling flow. Flow mixing in an enlarged heat transfer area by the WBD core is responsible for the substantial heat transfer enhancement. The WBD core is mechanically strong yet light while providing a substantial reduction in a brake's operating temperature.

FIGURES IN THIS ARTICLE
<>
Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 2

WBD and its integration into a ventilated brake disk: (a) fabrication of WBD and its morphology; (b) a quarter of an annular WBD core; (c) a WBD brake disk showing aerodynamic anisotropy

Grahic Jump Location
Fig. 5

Rotating test setup: (a) for transient heat transfer measurement and braking test; (b) for steady-state heat transfer measurement; and (c) test section for cooling flow rate measurement

Grahic Jump Location
Fig. 6

Measured axial velocity profiles in the circular intake duct normalized by the centerline velocity (Uc)

Grahic Jump Location
Fig. 7

Inlet flow pattern visualized by helium bubbles

Grahic Jump Location
Fig. 4

Stationary test setup for pressure drop and heat transfer measurements

Grahic Jump Location
Fig. 3

Geometric details of the pin-finned brake disk showing three periods of the core topology

Grahic Jump Location
Fig. 1

Schematics of a disk brake system: (a) components and (b) current ventilated brake disks with vanes and pin fins

Grahic Jump Location
Fig. 8

Comparison of cooling performance of both brake disks, simulating 2% gradient continuous downhill braking at a vehicle speed of 40 km/h (i.e., 200 rpm) and a braking power of 1.9 kW: (a) transient local surface temperature; (b) transient mean surface temperature; and (c) radial temperature profile

Grahic Jump Location
Fig. 9

Measured steady-state heat transfer characteristics: (a) surface temperature distribution at 1000 rpm and (b) area-averaged Nusselt number with the rotational Reynolds number

Grahic Jump Location
Fig. 10

Measured inner endwall temperature maps by the IR camera for stationary cooling (ReDh = 14,400): (a) the pin-finned disk and (b) the WBD disk

Grahic Jump Location
Fig. 11

Measured temperature profiles normalized by mean temperature: (a) azimuthal profile (III(a)) and (b) radial profile at θ = 22.5 deg (III(b))

Grahic Jump Location
Fig. 12

Measured exit radial velocity profile indicating strong flow anisotropy through the WBD core (ReDh = 14,400)

Grahic Jump Location
Fig. 13

Pressure drop characteristics for both stationary brake disks: (a) pressure drop versus coolant inlet velocity and (b) friction factor versus Reynolds number

Grahic Jump Location
Fig. 14

Pumping capacities of the both brake disks as a function of the brake disk's rotational speed

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In