Compressible Pipe Flow with Friction and Gravity

Numerical Studies of Unsteady Friction in Transient Pipe Flow

In this thesis, unsteady friction in transient pipe flow is given a closer look. The common quasi-steady friction model and two one-dimensional convolution-based models, developed by Zarzycki and Vardy & Brown, are considered. A quasi-two-dimensional approach to the water hammer problem is also derived, where the pipe friction is related to the near-wall behavior of the velocity profile. The mo...

Turbulent bubbly flow in pipe under gravity and microgravity conditions

Large eddy simulation of compressible turbulent pipe flow with heat transfer

A compressible finite volume formulation for large eddy simulation (LES) of turbulent channel flows was extended to solve the turbulent flows in pipes and annular passages. A general finite volume scheme was developed based on conservation equations in Cartesian coordinates with non-Cartesian control volumes. A dual-time stepping approach with time derivative preconditioning was employed and ti...

Turbulence Intensity and the Friction Factor for Smooth- and Rough-Wall Pipe Flow

Abstract: Turbulence intensity profiles are compared for smoothand rough-wall pipe flow measurements made in the Princeton Superpipe. The profile development in the transition from hydraulically smooth to fully rough flow displays a propagating sequence from the pipe wall towards the pipe axis. The scaling of turbulence intensity with Reynolds number shows that the smoothand rough-wall level de...

Numerical Study On Local Entropy Generation In Compressible Flow Through A Suddenly Expanding Pipe

This study presents the investigation of the local entropy generation in compressible flow through a suddenly expanding pipe. Air is used as fluid. The air enters into the pipe with a turbulent profile using 1/7 th power law. The simulations are extended to include different expansion ratios reduced gradually from 5 to 1. To determine the effects of the mass flux, φ′ ′ , the ambient heat transf...