In this paper a finite-difference-based lattice Boltzmann method for curvilinear coordinates is proposed in order to improve the computational efficiency and numerical stability of a recent method [R. Mei and W. Shyy, J. Comput. Phys. 143, 426 (1998)] in which the collision term of the Boltzmann Bhatnagar-Gross-Krook equation for discrete velocities is treated implicitly. In the present method,...

in this paper, analysis of fluid flow and heat transfer over the bank of tubes is considered. k-ω sst model is applied for simulation of turbulent flow. in this paper, the improvement of efficiency of a bundle of circular tubes by changing the shape of the cross section of one row of the pipes to the elliptical cross section as an innovative plan is considered. as know, friction factor in turbu...

in this study, flow characteristics through symmetric stenosis artery are investigated. the shape of eccentricity for stenotic flows is limited by circular-cross sections and plaques are usually assumed as to be oriented concentrically. thegoverningequationsaretheusualnavier-stokesequationsandare numericallysolved by using finite volumemethod in arbitrary orthogonal curvilinear coordinates. in ad...

When depth of flow past a river bridge exceeds opening under the bridge, the flow under the bridge becomes pressurized. The water is directed downward and under the bridge deck, causing increase in velocity and shear stress on the bed thereby increasing bed scour. This is termed as Pressure Flow Scour. The present study investigates the phenomenon of pressure flow scour resulting from a submerg...

the momentum equation in the kinematic wave model is a power-law equation with two parameters. these parameters, which relate the discharge to the flow area, are commonly derived using manning’s equation. in general, the values of these parameters depend on the flow depth except for some special cross sections. in this paper, improved estimates of the kinematic wave parameters for circular chan...