Sains Ma1aysiana 33(1): 15-27 (2004)                                                                          Pengajian Kuantitatif/

                                                                                                                                        Quantitative Studies

Unsteady Mixed Convection near the Forward Stagnation

Point of a Two-Dimensional Symmetric Body

Prescribed with a Constant Wall Heat Flux

Roslinda Nazar

School of Mathematical Sciences

Faculty of Science & Technology

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

Ioan Pop

Faculty of Mathematics

University of Cluj

R-3400 Cluj, CP 253, Romania

ABSTRAK

Dalam makalah ini, kajian terhadap masalah aliran lapisan sempadan olakan campuran tak mantap berhampiran titik genangan ke depan bagi suatu jasad simetri dua dimensi dengan kadar fluks haba yang seragam dibincangkan.  Tujuan utama kajian ini adalah untuk mengenal pasti situasi di mana penyelesaian dual bagi aliran keadaaan mantap boleh ditentukan, apabila aliran menentang berlaku. Di samping itu, dalam kajian ini juga didapati bahawa terdapat peralihan yang licin dari aliran awal tak mantap (bagi masa yang pendek) ke aliran akhir mantap (bagi masa yang panjang).

ABSTRACT

The unsteady mixed convection boundary layer flow near the forward stagnation point of a two-dimensional symmetric body prescribed by a uniform heat flux rate is studied in this paper.  The main aim of the investigation is to identify situations in which dual solutions for the steady-state flow can be determined when the flow is opposing.  It is also shown that there is a smooth transition from the unsteady initial flow (short time) to the final steady state flow (large time).

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