Nonsimilar incompressible laminar boundary layers with magnetic field
Tóm tắt
The solution of the steady laminar incompressible nonsimilar magneto-hydrodynamic boundary layer flow and heat transfer problem with viscous dissipation for electrically conducting fluids over two-dimensional and axisymmetric bodies with pressure gradient and magnetic field has been presented. The partial differential equations governing the flow have been solved numerically using an implicit finite-difference scheme. The computations have been carried out for flow over a cylinder and a sphere. The results indicate that the magnetic field tends to delay or prevent separation. The heat transfer strongly depends on the viscous dissipation parameter. When the dissipation parameter is positive (i.e. when the temperature of the wall is greater than the freestream temperature) and exceeds a certain value, the hot wall ceases to be cooled by the stream of cooler air because the ‘heat cushion’ provided by the frictional heat prevents cooling whereas the effect of the magnetic field is to remove the ‘heat cushion’ so that the wall continues to be cooled. The results are found to be in good agreement with those of the local similarity and local nonsimilarity methods except near the point of separation, but they are in excellent agreement with those of the difference-differential technique even near the point of separation.
Tài liệu tham khảo
Cess R D 1960Trans. ASME J. Heat Transfer 82 87
Davies T V 1963Proc. R. Soc. A273 496
Dewey C F Jr and Gross J A 1967Advances in Heat Transfer (New York: Academic Press) Vol. 4 p 317
Glauert M B 1961J. Fluid Mech. 10 276
Heiser W H and Bornhorst W J 1966AIAA J. 4 1139
Hildyard L T 1972Phys. Fluids 15 1023
Marvin J G and Sheaffer Y S 1969 NASA TND-5516
Rossow V J 1957 NACA TN-3971
Schlichting H 1968Boundary Layer Theory (New York: McGraw Hill) 6th ed. p. 284
Sherman A 1961Phys. Fluids 4 552
Smith A M O and Clutter D W 1963AIAA J. 1 2062
Sparrow E M, Quack H and Boerner C J 1970AIAA J 8 1936
Sparrow E M and Yu H S 1971Trans ASME J. Heat Transfer 93 328
Terrill R M 1960Phys. Trans. R. Soc. A253 (1022) 55
Vimala C S and Nath G 1975J. Fluid Mech. 70 561