Journal of Applied Sciences1812-56541812-5662Asian Network for Scientific Information10.3923/jas.2001.275.282ShiraniE.H. Nasibi3200113A body fitted curvilinear coordinate system is incorporated with Beam-Warming numerical method to solve full Navier-Stokes and energy equations for laminar flow of air around three isothermal horizontal cylinders in an in-line tube bank. The effects of longitudinal and transverse pitches and Reynolds number ranged from 25 to 2500 on the flow parameters such as streamlines, surface pressure, total drag, pressure drag and friction drag coefficients and hydraulic drag around tube banks are considered. The change of longitudinal and transverse pitches and the Reynolds number affects the flow parameters. As longitudinal pitch is decreased, the wakes behind the cylinders are spread between two rows. There is an optimum value for longitudinal pitch, at which, the hydraulic drag is minimum. The drag coefficient as Reynolds number increased or as the transverse pitch increased.]]>Richard, M.B. and R.F. Warming,1976Cantwell, B. and D. Coles,1983Chen, C.K., K.L. Wong and J.W. Cleaver,1986Chen, C.J. and K.M. Obasih,1986Jang, J.Y., J.T. Lai and L.C. Liu,1998Farell, C. and J. Blessmann,1983Gowda, Y.T.K., P.A.A. Narayana and K.N. Seetharamu,1998Launder, B.E. and T.H. Massey,1978Martin, A.R., C. Saltiel and W. Shyy,1998Pulliam, T.H. and J.L. Steger,1980Song, C.C.S. and M. Yuan,1990Zukauskas, A.,1987