MeshPhysicsGeometryVerification of Laminar and Validation of Turbulent Pipe Flows58:160 Intermediate Mechanics of FluidsCFD LAB 1First input the refinement ratio you will use for the “coarse”, “medium”, and “fine” meshes.“Monitor location” is used to specify the locations for line monitors (verification of axial velocity profile), click that will pop out the following window:5. ExercisesVerification of Laminar and Validation of Turbulent Pipe Flows 58:160 Intermediate Mechanics of Fluids CFD LAB 1By Tao Xing and Fred SternIIHR-Hydroscience & EngineeringThe University of IowaC. Maxwell Stanley Hydraulics LaboratoryIowa City, IA 52242-15851. Purpose The Purpose of CFD Lab 1 is to simulate steady laminar and turbulent pipe flow following the “CFDProcess” by an interactive step-by-step approach. Students will have “hands-on” experiences usingFlowLab to compute axial velocity profile, centerline velocity, centerline pressure, and friction factor.Students will conduct verification studies for friction factor and axial velocity profile of laminarpipe flows, including iterative error and grid uncertainties, and effect of refinement ratio onverification. Students will validate turbulent pipe flow simulation using EFD data, analyze thedifferences between laminar and turbulent flows, and present results in CFD Lab report.Flow Chart for ISTUE Teaching Module for Pipe Flow (red color illustrates the options you willuse in CFD Lab 1)1CoarseMediumFineAutomaticManualStructuredUnstruct-uredGeometryPhysicsMeshTotal pressuredropPost-processingWall friction forceCenterline VelocityCenterline Pressure Profiles of Axial VelocityContoursVectorsStreamlinesPipePipe RadiusPipe LengthXY plotValidationVerification BoundaryConditionsFlowPropertiesViscousModelsOne Eq.Two Eq.Density and viscosityLaminarTurbulenInviscidSAk-ek-wHeatTransfer?Incompress-ible?InitialConditionsSolveIterations/StepsConverge-ntLimitPrecisionsSingleDoubleNumerical Schemes1st orderupwind 2nd order upwindQuickSteady/Unsteady?ReportResidual2. Simulation DesignIn CFD Lab 1, simulation will be conducted for laminar and turbulent pipe flows. Iterative error and grid uncertainties will be studied. Comparison between CFD and AFD for laminar flow, and CFD and EFD for turbulent flow will be performed. The problem to be solved is that of laminar/turbulent flows through a circular pipe. Reynolds numberis 655 for laminar flow and 111,569 for turbulent pipe flow, based on pipe diameter. Since the flow is axisymmetric we only need to solve the flow in a single plane from the centerline tothe pipe wall. Boundary conditions need to be specified include inlet, outlet, wall, and axis, as willbe described details later. Uniform flow was specified at inlet, the flow will reach the fully developedregions after a certain distance downstream. No-slip boundary condition will be used on the wall andconstant pressure for outlet. Symmetric boundary condition will be applied on the pipe axis.All analytical data (AFD) for Laminar Pipe Flow and EFD data for turbulent pipe flow can bedownloaded from the class website (http://css.engineering.uiowa.edu/~me_160). 3. CFD Educational InterfaceRight after you launch FlowLab 1.2.10, the following interface will be shown. The top right cornerillustrates the CFD processes: GeometryPhysicsMeshSolveReportsPost-processing.There is also a sketch window that shows the definition of all boundary conditions and coordinates.OutletInletSymmetry AxisPipe Wall2If you close the sketch window and want to see it again, you can click <<File>><<ProblemOverview>>. You MUST save your work regularly to avoid any possible lost of your data and jobs.<<File>><<Save As>>. Then use the <<Browse>> button to locate the directory where you want tosave. It is recommended that you created your own folder in the FlowLab working directory:C:\Documents and Settings\Fluidslab\myflowlab\YOURNAME\.4. CFD ProcessStep 1: (Geometry)1. Radius of pipe (0.02619 m)2. Length of pipe (7.62 m) Click <<Create>>, after you see the pipe geometry created, click <<Next>>.Step 2: (Physics)3The Reynolds number shown in the above figure is for “laminar” pipe flow case, for “turbulent” pipeflow, the Reynolds number will be different based on the inlet velocity you specified.1. With or without Heat Transfer?Thermal effects are not considered in CFD Lab 1, turn OFF <<Heat Transfer >> button.2. Incompressible or compressibleChoose “Incompressible”, which is the default setup.3. Flow Propertiesuse the values shown in the above figure. Input the values and click <<OK>>.4. Viscous Model In CFD Lab 1, both laminar model and turbulent model (k-e) will be used, follow exercise notes forspecifications, and click <<OK>>. Note: For each simulation, you can only choose one model,either laminar model OR turbulent k-e model.45. Boundary ConditionsAt “Inlet”, FlowLab use zero gradient for pressure and fix the velocity to be 0.2 m s and 34.08 m s,for laminar and turbulent pipe flows, respectively. Use default values for “intensity” and “lengthscale”.At “Axis”, FlowLab use zero gradient for axial velocity and Pressure and specify the magnitude forradial velocity to be zero. Read all the values and click <<OK>>.At “Outlet”, FlowLab uses magnitude for pressure and zero gradients for axial and radial velocitiesand turbulent quantities. For pressure magnitude, use “0” for laminar flow and “400 Pa” for turbulentflow, click <<OK>>.5LaminarTurbulentLaminarTurbulentAt “Wall”, no-slip boundary conditions are fixed for both axial and radial velocity, gradients for othervariables are zero. For turbulent pipe flow, pipe roughness also needs to be specified, which is 2.5e-5m in this lab. Read the panel, input pipe roughness and click <<OK>>.6. Initial ConditionsUse the default setup for initial conditions.6LaminarTurbulentLaminarTurbulentLaminarAfter specifying all the above parameters, click <<Compute>> button and FlowLab will automaticallycalculate the Reynolds number based on the inlet velocity and pipe diameter you input. Note: Forturbulent pipe flow, the outlet pressure is 400 Pa, you may specify pressure magnitude in “initialcondition” to be 400 Pa to speed up convergence. Click the <<Next>>, this takes you to the nextstep,
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