Sains Malaysiana 41(10)(2012): 1263–1270

 

Aliran Genangan bagi Bendalir Mikrokutub terhadap Permukaan Mencancang yang

Telap dengan Fluks Haba Boleh Ubah

(Stagnation Flow of a Micropolar Fluid towards a Vertical Permeable Surface with

Prescribed Heat Flux)

 

W.M.K.A Wan Zaimi

Institut Matematik Kejuruteraan, Kampus Pauh Putra, Universiti Malaysia Perlis, 02000 Arau, Perlis, Malaysia

 

Anuar Ishak*

Pusat Pengajian Sains Matematik, Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

 

Received: 27 March 2012 / Accepted: 21 May 2012

 

ABSTRAK

Dalam makalah ini, masalah aliran genangan dalam bendalir mikrokutub terhadap permukaan mencancang yang telap dengan fluks haba boleh ubah dipertimbangkan. Dengan menggunakan penjelmaan keserupaan, persamaan asas yang menakluk aliran bendalir dan pemindahan haba dijelmakan kepada satu set persamaan perbezaan biasa. Persamaan yang dijelmakan tertakluk kepada syarat-syarat sempadan yang berkaitan kemudiannya diselesaikan secara berangka menggunakan kaedah tembakan. Kesan parameter sedutan/semburan fw ke atas profil halaju dan suhu serta pekali geseran kulit dan nombor Nusselt setempat diperoleh dan dibincangkan. Keputusan berangka menunjukkan bahawa penyelesaian dual wujud dalam kedua-dua aliran membantu dan aliran menentang.

 

Kata kunci: Aliran genangan; bendalir mikrokutub; mekanik bendalir; penyelesaian dual; sedutan/semburan

 

ABSTRACT

This paper deals with the stagnation flow of a micropolar fluid towards a vertical permeable surface with prescribed heat flux. By using a similarity transformation, the basic equations governing the fluid flow and heat transfer are transformed into a set of ordinary differential equations. The transformed equations subjected to the associated boundary conditions are then solved numerically using the shooting method. The effects of suction/injection parameter fw on the velocity and the temperature profiles as well as the skin friction coefficient and the local Nusselt number are obtained and discussed. The numerical results indicate that dual solutions exist in both assisting and opposing flows.

 

Keywords: Dual solutions; fluid mechanics; micropolar fluid; stagnation flow; suction/injection

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*Corresponding author; email: anuar_mi@ukm.my

 

 

 

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