THERMAL ENTRANCE REGION HEAT TRANSFER FOR RECTANGULAR DUCTS OF VARIOUS ASPECT RATIOS AND PECLET NUMBERS

Abstract

In this investigation the thermal entrance region problem is solved for flow in rectangular ducts of various aspect ratios and for various Peclet numbers. The assumptions under which the problem is solved are steady, fully developed laminar velocity profile, constant fluid properties of viscosity, density, specific heat and thermal conductivity, constant wall temperature, and a uniform inlet fluid temperature. Included in the solution are axial conduction and viscous dissipation. The method of B. G. Galerkin is used to formulate an approximate series solution of the problem. The data presented include bulk mean temperature, local Nusselt number, and the ratio of the local heat-transfer rate to the long wall to the local heat-transfer rate to the short wall. It is concluded that for low Peclet numbers, neglecting the axial conduction term leads to considerable error in the solution.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1969
Accession Number
AD0693564

Entities

People

  • J. R. Dewitt
  • W. T. Snyder

Organizations

  • Arnold Engineering Development Complex

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Abstracts
  • Air Force
  • Aspect Ratio
  • Boundaries
  • Classification
  • Conductivity
  • Dissipation
  • Eigenvalues
  • Energy
  • Equations
  • Flow
  • Heat Transfer
  • Laminar Flow
  • Pressure Gradients
  • Specific Heat
  • Thermal Conductivity
  • Viscosity

Readers

  • Combustion and Flow Dynamics.
  • Fluid Dynamics.