Flow resistance of curved square pipes with rough surfaces.

Prediction of turbulent flow in curved pipes

A finite-difference procedure is employed to predict the development of turbulent flow in curved pipes. The turbulence model used involves the solution of two differential equations, one for the kinetic energy of the turbulence and the other for its dissipation rate. The predicted total-velocity contours for the developing flow in a 180’ bend are compared with the experimental data. Predictions...

Turbulent flow in smooth and rough pipes.

Recent experiments at Princeton University have revealed aspects of smooth pipe flow behaviour that suggest a more complex scaling than previously noted. In particular, the pressure gradient results yield a new friction factor relationship for smooth pipes, and the velocity profiles indicate the presence of a power-law region near the wall and, for Reynolds numbers greater than about 400x103 (R...

Mathematical modeling of hydraulic resistance in pipes with rough walls

Study patterns of flow in pipes with rough walls can be considered relevant, as the use of rough surfaces is a method of heat transfer. In the theoretical study of heat transfer processes in heat exchangers and devices used in various fields of technology, it is very important to know the basic laws of flow in rough pipes in turbulent regime. Flow patterns for rough pipes differs from the behav...

ricci flow of negatively curved incomplete surfaces

We show uniqueness of Ricci flows starting at a surface of uniformly negative curvature, with the assumption that the flows become complete instantaneously. Together with the more general existence result proved in [10], this settles the issue of well-posedness in this class.

Frequency-dependent viscous flow in channels with fractal rough surfaces