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Title: Liquid crystal visualization and computer modeling of enhanced heat transfer on a flat plate in forced convection

Abstract

This paper presents the results of an experimental and computational study of heat transfer enhancement found in the vicinity of a three dimensional block placed on a constant heat flux plate in turbulent forced convection. The experiments used thermochromic liquid crystals to visualize temperature on the surface. Photographs were taken to establish temperature contour lines at a range of velocities and a variety of block sizes and configurations. The results show heat transfer enhancement exists upstream and downstream of the blocks. The enhancement is caused by a horse shoe vortex which stagnates on the front surface of the block and then wraps around the sides. Thin blocks (narrow in the flow direction) show the best enhancement. The computer simulations used the {kappa}-epsilon turbulence model and had reasonable qualitative agreement with the experiments.

Authors:
;  [1]
  1. Union Coll., Schenectady, NY (United States). Dept. of Mechanical Engineering
Publication Date:
OSTI Identifier:
418156
Report Number(s):
CONF-960815-
ISBN 0-7918-1513-7; TRN: IM9705%%534
Resource Type:
Book
Resource Relation:
Conference: 31. national heat transfer conference, Houston, TX (United States), 3-6 Aug 1996; Other Information: PBD: 1996; Related Information: Is Part Of ASME proceedings of the 31. national heat transfer conference: Volume 9. HTD-Volume 331; Hadim, H.A. [ed.] [Stevens Institute of Technology, Hoboken, NJ (United States)]; Charmchi, M. [ed.] [Univ. of Massachusetts, Amherst, MA (United States)]; Cochran, R. [ed.] [Sandia National Labs., Albuquerque, NM (United States)]; Ramaswamy, B. [ed.] [Rice Univ., Houston, TX (United States)]; Figliola, R.S. [ed.] [Clemson Univ., Georgetown, SC (United States)]; PB: 158 p.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; HEAT TRANSFER; AUGMENTATION; EXPERIMENTAL DATA; THEORETICAL DATA; FORCED CONVECTION; TEMPERATURE GRADIENTS; FLOW MODELS; TEMPERATURE MEASUREMENT; TURBULENT FLOW

Citation Formats

Voegler, G.R., and Anderson, A.M. Liquid crystal visualization and computer modeling of enhanced heat transfer on a flat plate in forced convection. United States: N. p., 1996. Web.
Voegler, G.R., & Anderson, A.M. Liquid crystal visualization and computer modeling of enhanced heat transfer on a flat plate in forced convection. United States.
Voegler, G.R., and Anderson, A.M. 1996. "Liquid crystal visualization and computer modeling of enhanced heat transfer on a flat plate in forced convection". United States. doi:.
@article{osti_418156,
title = {Liquid crystal visualization and computer modeling of enhanced heat transfer on a flat plate in forced convection},
author = {Voegler, G.R. and Anderson, A.M.},
abstractNote = {This paper presents the results of an experimental and computational study of heat transfer enhancement found in the vicinity of a three dimensional block placed on a constant heat flux plate in turbulent forced convection. The experiments used thermochromic liquid crystals to visualize temperature on the surface. Photographs were taken to establish temperature contour lines at a range of velocities and a variety of block sizes and configurations. The results show heat transfer enhancement exists upstream and downstream of the blocks. The enhancement is caused by a horse shoe vortex which stagnates on the front surface of the block and then wraps around the sides. Thin blocks (narrow in the flow direction) show the best enhancement. The computer simulations used the {kappa}-epsilon turbulence model and had reasonable qualitative agreement with the experiments.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1996,
month =
}

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