Unsteady mixed convection boundary layer flow near the stagnation point on a vertical surface in a porous medium

Roslinda Mohd. Nazar, Norsarahaida Amin, Ioan Pop

Research output: Contribution to journalArticle

62 Citations (Scopus)

Abstract

The unsteady mixed convection boundary layer flow near the region of a stagnation point on a vertical surface embedded in a Darcian fluid-saturated porous medium is studied in this paper. It is assumed that the unsteadiness is caused by the impulsive motion of the free stream velocity and by sudden increase in the surface temperature. The problem is reduced to a single partial differential equation, which is solved numerically using the Keller-Box method. The small time (initial unsteady flow) as well as the large time (final steady state flow) solutions are also included in the analysis. The asymptotic behavior of the solution for small and large values of the mixed convection parameter λ is also examined when the flow becomes steady. It is shown that there is a smooth transition from the small time solution to the large time solution. It is also shown that there is an excellent agreement between the numerical and analytical solutions. The uniqueness of this problem lies on the fact that we have been able to show that in the case of steady state flow, solutions are possible for all values of λ>0 (assisting flow) and for λ<0 (opposing flow), solutions are possible only for a limited range of λ.

Original languageEnglish
Pages (from-to)2681-2688
Number of pages8
JournalInternational Journal of Heat and Mass Transfer
Volume47
Issue number12-13
DOIs
Publication statusPublished - Jun 2004

Fingerprint

Mixed convection
boundary layer flow
stagnation point
Boundary layer flow
Porous materials
convection
equilibrium flow
unsteady flow
free flow
steady flow
Steady flow
Unsteady flow
uniqueness
partial differential equations
surface temperature
Partial differential equations
boxes
Fluids
fluids
Temperature

Keywords

  • Analytical solution
  • Boundary layer
  • Flat plate
  • Mixed convection
  • Numerical solution
  • Stagnation point
  • Unsteady flow

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Energy(all)
  • Mechanical Engineering

Cite this

Unsteady mixed convection boundary layer flow near the stagnation point on a vertical surface in a porous medium. / Mohd. Nazar, Roslinda; Amin, Norsarahaida; Pop, Ioan.

In: International Journal of Heat and Mass Transfer, Vol. 47, No. 12-13, 06.2004, p. 2681-2688.

Research output: Contribution to journalArticle

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