Sains Malaysiana 47(5)(2018): 1069–1076 
                  http://dx.doi.org/10.17576/jsm-2018-4705-25 
                      
              
                 
              
              Effects of Thermal
                Radiation on Mixed Convection Flow over a Permeable Vertical Shrinking Flat
                Plate in an Oldroyd-B Fluid
                
              
              (Kesan Sinaran Terma pada Aliran Olakan Campuran terhadap Plat Rata Telap Menegak Mengecut dalam Bendalir Oldroyd-B)
                
              
              
                 
              
              KOHILAVANI NAGANTHRAN1*, ROSLINDA NAZAR1 & IOAN POP2
                
              
              
                 
              
              1School of Mathematical Sciences, Faculty
                of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
                
              
              
                 
              
              2Department
                of Mathematics, Babeş-Bolyai University, R-400084
                Cluj-Napoca, Romania
                
              
              
                 
              
              Diserahkan: 14
                September 2017/Diterima: 12 Disember 2017
                
              
              
                 
              
              
                 
              
              ABSTRACT
                
              
              This study offers the
                numerical solutions for the problem of mixed convection stagnation-point flow
                along a permeable vertical flat plate in an Oldroyd-B
                fluid. The present investigation considers the effects of thermal radiation and
                heat generation/absorption in the fluid flow. The similarity transformation
                simplifies the complex model and the bvp4c function generates the numerical
                solutions according to the variations in the governing parameters. A higher
                degree of shrinking hastens flow separations. The dual solutions are visible in
                the range of buoyancy opposing flow. The results from this study may be useful
                for the scientist to understand the behaviour of the
                dilute polymer solutions in the industrial applications, for example, the drag
                reduction in pipe flows.
                
              
              
                 
              
              Keywords: Mixed
                convection; Oldroyd-B fluid; stability analysis;
                shrinking plate; stagnation-point flow 
                  
                
              
                 
              
              ABSTRAK
                
              
              Kajian ini memberikan penyelesaian berangka bagi masalah aliran titik genangan olakan campuran sepanjang plat rata telap menegak dalam bendalir Oldroyd-B. Kajian ini mempertimbangkan kesan sinaran terma dan penjanaan/penyerapan haba dalam aliran bendalir. Penjelmaan keserupaan mempermudahkan model kompleks dan fungsi bvp4c menghasilkan penyelesaian berangka mengikut variasi parameter menakluk. Darjah pengecutan yang lebih tinggi mempercepatkan pemisahan aliran. Penyelesaian dual boleh dilihat dalam julat aliran menentang apungan. Keputusan daripada kajian ini boleh digunakan oleh saintis untuk memahami tingkah laku larutan polimer cair dalam aplikasi perindustrian, contohnya pengurangan seretan dalam aliran paip.
                
              
              
                 
              
              Kata kunci: Aliran titik genangan; analisis kestabilan; bendalir Oldroyd-B; olakan campuran; plat mengecut
                
              
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              *Pengarang untuk surat-menyurat;
                email: kohi_kk@yahoo.com