For proper, design the junction of piping systems in power plants and process industries.
The cold fluid at 200C flows into the pipe through a large inlet and mixes with a warmer fluid at 400C that enters through a smaller inlet located at the elbow.
The CFD setup:
1- Model used: viscous model, k-epsilon (2eq), k-epsilon standard, enhanced wall treatment with energy model.
2- Boundary condition:
· For cold fluid inlet temp. 200C, inlet velocity 0.4m/s, turbulent intensity 5%, and hydraulic diameter 100mm (larger Diameter).
· For hot fluid inlet temp. 400C, inlet velocity 1.2m/s, turbulent intensity 5%, and hydraulic diameter 25mm (smaller Diameter).
· For outlet pressure gauge =0, and total pressure for Backflow method, and normal to boundary.
3- Solver: steady flow, pressured based and absolute velocity formation.
4- Solution method: Simple scheme, Green-guess node based discretization, 2nd order for pressure and 2nd order upwind for momentum and energy, also 1storder upwind for turbulence kinetic energy and dissipation rate.
5-Residuals are setup to10^-5 for all equation (energy, momentum, and turbulent stresses)