A modified fractional step method of keeping a constant mass flow rate in fully developed channel and pipe flows

Abstract

The objective of this paper is to present a modified fractional step method of keeping a constant mass flow rate in spatially periodic flows, because original fractional step methods do not precisely keep the mass flow rate constant in time. In the modified method, the mean and fluctuating pseudo-pressure gradients are separately obtained at each time step. This method is successfully applied to channel and pipe flows and shown to be suitable for maintaining a constant mass flow rate in time.

Influence of an anisotropic slip-length boundary condition on turbulent channel flow

“…Ref. 10). Simulations were conducted at two different Reynolds numbers Re = U δ/ν = 2810 and Re = 6250 based on the mean streamwise velocity U , the channel half-height δ and the kinematic viscosity ν, or Re τ0 = u τ0 δ/ν = 180 and Re τ0 = 360 based on friction velocity u τ0 in the reference case, which is a channel flow with standard no-slip boundary conditions on both walls.…”

Flow instability in baffled channel flow

“…In the other case, mass flux fluctuates while Dp is fixed in time. We adopted the former approach by following You et al (2000). The numerical resolution increases up to 256 Â 256 (for R B P 3) computing cells in x and y directions, respectively, as Re increases.…”

Study on improvement of compactness of a plate heat exchanger using a newly designed primary surface

“…Therefore two dimensionless parameters resulting from the normalization are derived as follows: bulk Reynolds number Re m = U m H/m and Prandtl number Pr = m/a where m and a represent kinematic viscosity and thermal diffusivity, respectively. In order to keep the mass flow rate constant in time for the present spatially periodic flow, a technique proposed by You et al [17] was adopted in the present study. In Eq.…”