Development and Verification of CFD Program by Central Difference Calculus for Incompressible Fluid

(Application to turbulence analysis)

Abstract

It was found that the Reynolds stress included in the Navier-Stokes equation of motion generated a negative quantity of ∇u→ . By canceling out this generated amount, a solution method that satisfied the following conditions was established.

1.Solutions satisfied the Navier-Stokes equation of motion

2.Solutions roughly satisfied the law of conservation of mass

3.Solutions did not diverge even if there were disturbances

Using this method, the turbulent tube friction coefficient of a smooth circular tube could be obtained. It was possible to show that the lower limit of the critical Reynolds number was 2300. Additionally, the method could be applied to analyze the flow around bluff bodies at high Reynolds numbers.