Plate Heat Exchanger CFD Simulation, ANSYS CFX

Description

Description

In this project, four solid plates are modeled while four pipes are placed at the corner of the plates. The fluid (water) flows through the pipes at the same velocity and at different temperatures (20 & 40 Celsius) in reverse directions.

The 2.5D geometry of the solution is modeled in Design Modeler software while all the solids and fluids are from one single part.

The solids are 2*2m, and their thickness is 0.1m; the pipe’s diameter and length are 0.15m and 1.1m, respectively.

The meshing process is done in ANSYS Meshing software. The elements are unstructured, while 5 layers of inflation is defined inside the pipes so that their total number is 5,096,686.

This CFD project is the 2nd episode of the ANSYS CFX Training Course.

Methodology: Plate Heat Exchanger CFD Simulation, ANSYS CFX

The simulation is independent of Time, so it has performed in steady state form. Moreover, the gravitational effects are ignored. There is convection between water and pipes and conduction phenomenon in the solids, transferring heat all over the domain. So, Conjugated Heat Transfer (CHT) was studied.

Heat Transfer is captured by Thermal Energy option and the turbulence model is k-Epsilon with Scalable Wall Function.

The Advection Scheme and Turbulence Numerics is set to High Resolution.

Results

Two-dimensional contours and vectors related to water pressure, temperature, turbulence kinetic energy, and velocity are obtained at the end of the solution procedure in CFD-Post software. As shown, water flows through the pipes in opposing directions at 20 ^oC and 40 ^oC. Mentioned amounts represent cold and hot temperatures.

Convection, which occurs between the fluid and pipe walls, is the earliest mechanism of heat transfer. Then it is the turn of conduction. Due to the conduction phenomena, heat from the water is transferred within the solid.

The figures show the temperature gradient as contour lines. It should be noted that fluid velocity is a crucial factor in how heat transfer is affected. The rate of convective heat transfer increases with the velocity of the water flow.