Case Studies > CFD
Case list
 Case 1: Cylindrical Vessel with FluidThermal Interaction
 Case 2: 2D FluidStructure Interaction
 Case 3: Fluid Flow in UShaped Vessel
 Case 4: 2D Fluid Flow
 Case 5: 3D Fluid Split and Mix
Case 1: Cylindrical Vessel with FluidThermal Interaction
Water flows through a cylindrical vessel and is heated by the heaters with contact temperature. The two heaters are represented by two "temperature" surfaces to simplify the whole model. Because of symmetry, only one quarter of the model is simulated. The inlet surface has a normal velocity with a value of 5[mm/s] defined in "Laminar Flow" physics type and has a initial temperature with a value of 20[degC] defined in "Heat Transfer in Fluids" physics type. "Temperature coupling" and "Flow coupling" are set up in "Multiphysics" analysis.
Fig 11 Schematic of cylindrical vessel with fluidthermal interaction, and the corresponding simplification

Fig 12 simulated velocity, pressure, temperature results and isotemperature surfaces

Case 2: 2D FluidStructure Interaction
This problem involves a fluidstructure interaction where the beam affects the flow path and the flow affects the beam deformation. The inlet is on the left having a normal inflow velocity, and the outlet is on the right having a zero pressure and a definition of "suppress backflow". The "Timedependent" solver with times (0 range(1.005,5e3,2)) is used to obtain the solution, in which the "Constant (Newton)" nonlinear method is applied.
Fig. 21 Schematic, mesh and simulated of 2D FluidStructure Interaction

Animation of water flow

Case 3: Fluid Flow in UShaped Vessel
Water flowing through a Ushaped vessel is simulated. Laminar flow physics type is defined for this engineering problem. The outer surface of Ushaped vessel is defined as "No slip" wall. One side is defined as the inlet with a normal inflow velocity, 1[m/s], and the other side is defined as the outlet with a pressure, 10 [Pa], and a setting of suppress backflow. The model is meshed using tetrahedral elements with "fine" mesh size. The "Timedependent" solver with a range of (0,0.025,2) is used to obtain the solution, in which the "Constant (Newton)" nonlinear method is applied.
Fig. 31 Ushaped vessel

Fig. 32 Tetrahedral mesh with "fine" mesh size

Case 4: 2D Fluid Flow
The model is to simulate 2D laminar flow using COMSOL Multiphysics. The upper and bottom lines are defined as noslip walls, and the boundary of three ellipses are defined as slip walls. The inlet is on the left having a normal inflow velocity, and the outlet is on the right having a pressure 10 psi and a definition of "suppress backflow". The "Timedependent" solver with ranges of (0,0.2,3) and (3.1,0.05,6) is used to obtain the solution, in which the "Constant (Newton)" nonlinear method is applied. Partials tracing mass are defined and released at t=3.6s.
Fig. 41 Schematic of 2D fluid flow

Animation of 2D fluid flow

Case 5: 3D Fluid Split and Mix
This example models a 3D split and combine mixer channel. A tracer fluid is introduced and mixed by multilamination. Two physics types are simulated: "Laninar flow" and "Transport of Diluted Species", which are studies in two "Stationary" steps. Two inlets have a normal inflow velocity of 1[mm/s] and one outlet has a zero pressure. One inflow has zero concentration and the other has a concentration of 1 mol/m^3.


Fig. 61 Schematic and mesh of 3D fluid split and mix

Fig. 62 Simulated results of 3D fluid split and mix
