Results from direct numerical simulations for three dimensional Rayleigh-Bénard convection in a cylindrical cell of aspect ratio 1/2 and Pr = 0.7 are presented. They span five decades of Ra from 2× 10 to 2× 10. Good numerical resolution with grid spacing ∼ Kolmogorov scale turns out to be crucial to accurately calculate the Nusselt number, which is in good agreement with the experimental data b...

We construct a new numerical method for computing reference numerical solutions to the self–similar solution to the problem of incompressible laminar flow past a thin flat plate with suction–blowing. The method generates global numerical approximations to the velocity components and their scaled derivatives for arbitrary values of the Reynolds number in the range [1,∞) on a domain including the...

The optimum suction distribution which gives the longest laminar region for a given total suction is computed. The goal here is to provide the designer with a method to find the best suction distribution subject to some overall constraint applied to the suction. We formulate the problem using the Lagrangian multiplier method with constraints. The resulting non-linear system of equations is solv...

In the present work, thermo-fluidic behavior of a heat exchanger tube with conical shaped insert has been investigated help finite volume method. To enhance transfer rate, two different types roughness used in i.e. protrusion and dimple roughness. A three-dimensional computational model RNG turbulence is for simulation it performed three diameters (3 mm, 6 mm 9 mm) pitch space (120 180 both The...

The development of the boundary layer along a long thin cylinder aligned with the flow is considered. Numerical solutions are presented and compared with previous asymptotic results. Very near the leading edge the flow is given by the Blasius solution for a flat plate. However, there is soon a significant deviation from Blasius flow, with a thinner boundary layer and higher wall shear stress. L...