About the Pipe Flow Module
What Can the Pipe Flow Module Do?
The Pipe Flow Module is intended for the modeling and simulation of flow of fluids in the pipes and channel systems, as well as compressible hydraulic transients and acoustics waves. Typical simulations yield the velocity, pressure variation, and temperature in systems of pipes and channels. Hydraulic transients resulting from a valve that is closed rapidly in a pipe network is referred to as water hammer, which can be modeled too. This module has extra functionality for computing displacements, rotations, stresses, and strains in the pipes. The module can be used to design and optimize complex cooling systems in turbines, ventilation systems in buildings, pipe systems in chemical processes, and lines in the oil and gas industry.
In common for pipes and channels that can be modeled using the Pipe Flow Module is that the pipe length is large enough so that the flow inside can be considered fully developed. Piping components such as bends, valves, T-junctions, contractions/expansions, and pumps are also available in the module.
The Pipe Flow Module includes these physics interfaces:
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The Pipe Flow interface computes the pressure and velocity field in isothermal pipe systems.
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The Heat Transfer in Pipes interface computes the energy balance in pipe systems but receives the flow field as a value or as a known solved field. Wall heat transfer to the surroundings is included.
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The Transport of Diluted Species in Pipes interface solves a mass balance equation for pipes in order to compute the concentration distribution of a solute in a dilute solution, considering diffusion, dispersion, convection, and chemical reactions.
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The Nonisothermal Pipe Flow interface is a multiphysics interface that solves the flow, pressure, and temperature simultaneously and fully coupled.
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The Reacting Pipe Flow interface is a multiphysics interface that solves the flow, pressure, temperature, and reacting species transport simultaneously and fully coupled.
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The Water Hammer interface solves rapid hydraulic transients in pipe systems, taking the elastic properties of both the fluid and pipe wall into account.
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The Pipe Acoustics, Frequency Domain interface models sound waves in flexible pipe systems, with the assumption of harmonic vibrations.
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The Pipe Acoustics, Transient interface models sound waves in flexible pipe systems with arbitrary transient variations in pressure.
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The Pipe Mechanics interface analyzes the stresses and deformations in pipes.
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The Fluid-Pipe Interaction, Fixed Geometry interface can be used to model problems where the forces from the fluid in a piping system act as structural loads.
The physics interfaces in the module define the conservation of momentum, energy, and mass of a fluid inside a pipe or channel system. The flow, pressure, temperature, and concentration fields across the pipe cross sections are modeled as cross-section averaged quantities, which only vary along the length of the pipes and channels. The pressure losses along the length of a pipe or in a pipe component are described using friction factor expressions. A broad range of built-in expressions for Darcy friction factors cover the entire flow regime from laminar to turbulent flow, Newtonian and non-Newtonian fluids, different cross-sectional geometries, and a wide range of relative surface roughness values. In addition to the continuous frictional pressure drop along pipe stretches, pressure drops due to momentum changes in components such as bends, contractions, expansions, T-junctions and valves are computed through an extensive library of industry standard loss coefficients. Pumps are also available as components.
Building a COMSOL Multiphysics Model in the COMSOL Multiphysics Reference Manual