Tutorial Collection Efficiency Calculation And Running-Free PDF

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Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,In this tutorial you will learn. How to couple EWF model with Eulerian multiphase approach to create film. Use of EWF model to determine collection efficiency. How to model particle stripping, How to see particles separated or stripped from film. Prerequisites, This tutorial is written with the assumption that you have completed Tutorial 1 from the. ANSYS FLUENT 14 0 Tutorial Guide and that you are familiar with the ANSYS FLUENT. navigation panels and the menu structure Therefore some steps in the setup and solution. procedure will not be shown explicitly,Preparation. 1 Copy the files NACA 0012 msh film accretion c to the working folder. 2 Use FLUENT 14 Launcher to start the 3DDP version of ANSYS FLUENT. Setup and Solution,Stage1 Solution of Multiphase flow.
In this section we will be discussing the setup and solution of flow of air water droplets. mixture over the wing surface We will use Eulerian multiphase approach to model this flow. Step 1 Mesh,1 Read the mesh file NACA 0012 msh,File Read Mesh. 2 Change the view,Display Views Front,3 Display Mesh on symmetry plane. Display Mesh sym 1,a Zoom in as shown in below figure. b Give name as view1 and click save, Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Fig 1 Mesh distribution in sym 1.
Step 2 General Settings,1 Check the mesh,a General Check. ANSYS FLUENT performs various checks on the mesh and reports the. progress in the console Pay attention to the minimum volume reported and. make sure this is a positive number, Note Warning for high aspect ratio cells is because of very fine mesh near the wing. surface to resolve the boundary layer This warning can be ignored. Step 3 Models,1 Setup Multiphase Model,Models Multiphase Edit. a Select Eulerian under model,b Click OK to close the Multiphase Model. 2 Enable the Energy Equation,Models Energy Edit,a Click ok to close the Energy panel.
Click ok in the information dialogue box, Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,3 Select the Standard k epsilon turbulence model. Models Viscous Edit,a Select k epsilon 2 eqn,b Ensure that Standard under k epsilon Model. c Ensure Standard Wall Functions under Near Wall Treatment. Step 4 Materials,1 Change the material properties,Materials Air Create Edit. a Change density to ideal gas,b Click Change Create.
2 Add water liquid, a Click Fluent Database to open the Fluent Database Materials panel. b Select water liquid h2o l from the Fluent Fluid Material list. c Click Copy and close the Fluent Database Materials and Materials panel. d Change the Name to water liquid eulerian, Note This will allow choosing same water liquid material for DPM Phase in. later stage,e Change Chemical Formula to h2o l e,f Click Change Create. g Click Yes to overwrite,h Close the Material Panel. Step 5 Phases,1 Set Phase 1 Primary Phase,Phases Phase 1 Primary Phase Edit.
a Change the name to air,b Select Phase Material as air. c Click OK to close the Primary Phase dialogue box. Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,2 Set Phase 2 Secondary Phase. Phases Phase 2 Secondary Phase Edit,a Change the name to water liquid eulerian. b Select Phase Material as water liquid eulerian,c Change the diameter to 1 6e 05. d Click OK to close the Secondary Phase dialogue box. Step 6 Boundary Conditions,Boundary Conditions, 1 Set the boundary conditions for mixture phase at far field 1 zone.
Boundary Conditions far field 1,a Ensure that Pressure inlet is selected. b Select Mixture under Phase,c Click edit and set the following values. Parameters Values,Gauge Total Pressure Pa 11809 64. Supersonic Initial Gauge Pressure Pa 0,Direction Specification Method Direction Vector. Turbulence Specification Method Intensity and Viscosity Ratio. Turbulence Intensity 1,Turbulent Viscosity Ratio 5.
d Click OK to close the Pressure inlet panel, 2 Set the boundary conditions for air phase at far field 1 zone. Boundary Conditions far field 1,a Select air under Phase. b Click edit,Parameters Values,X Component of Flow Direction 0 9961947. Y Component of Flow Direction 0 0871557,Z Component of Flow Direction 0. Total Temperature K 309 6, Note You have to go to Thermal tab to set Total Temperature.
Tutorial Collection efficiency calculation and running wet and run. back analysis on wing, 3 Set the boundary conditions for water liquid eulerian phase at far field 1 zone. Boundary Conditions far field 1,c Select water liquid eulerian under Phase. d Click edit,Parameters Values,X Component of Flow Direction 0 9961947. Y Component of Flow Direction 0 0871557,Z Component of Flow Direction 0. Total Temperature K 309 6,Volume Fraction 1e 06, Note You have to go to Multiphase tab to set Volume Fraction.
4 Set the boundary conditions for mixture phase at far field 2 zone. Boundary Conditions far field 2,a Ensure that Pressure inlet is selected. e Select Mixture under Phase,f Click edit and set the following values. Parameters Values,Gauge Pressure Pa 0, Turbulence Specification Method Intensity and Viscosity Ratio. Turbulence Intensity 1,Turbulent Viscosity Ratio 5. g Click OK to close the Pressure inlet panel, 5 Set the boundary conditions for air phase at far field 2 zone.
Boundary Conditions far field 2,e Select air under Phase. f Click edit,g Set Backflow Total Temperature to 300 K. h Click OK to close the panel, 6 Set the boundary conditions for water liquid eulerian phase at far field 2 zone. Boundary Conditions far field 2,i Select water liquid eulerian under Phase. j Click edit, Tutorial Collection efficiency calculation and running wet and run.
back analysis on wing,k Set Backflow Total Temperature to 300 K. l Set Backflow Volume Fraction to Zero,7 Check Boundary Conditions for other zones. a Ensure that symmetry is selected for sym 1 and sym 2. b Ensure that wall is selected for wing lower and wing upper. Step 7 Solution Methods,Solution Methods,1 Set Solution Methods. a Set the following under solution methods,Pressure Velocity Phase Coupled SIMPLE. Coupling Scheme,Gradient Green Gauss Node Based, b Keep discretization schemes for other equations to default.
Step 8 Monitors,1 Set criteria for convergence,Monitors Residuals Edit. a Set Convergence criteria to none,b Ensure that plot is enabled. c Click OK to close the dialogue box,Step 9 Solution Initialization. Solution Initialization,1 Initialize the Solution, a Select Standard initialization under Initialization methods. b Select far field 1 under Compute from,c Click Initialize to initialize the solution.
Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Step 10 Save the case file,File Write Case. a Type the file name as airfoil step1 cas gz,Step 11 Run Calculation. Run Calculation,1 Set Run calculation parameters,a Enter 200 for number of iterations. b Click Calculate,Step 12 Save the case and data files. File Write Case data,a Type the file name as airfoil step1 cas gz.
Step 13 Post Processing,a Display residual, Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,b Display Velocity magnitude for air in sym 1. Note Make sure that view1 is selected in Display,Display Mesh. a Choose Faces under option, b Select wing lower wing upper under Surfaces click Display. c Zoom in and rotate wing surfaces to get view as shown in below figure. d Close the Panel, Tutorial Collection efficiency calculation and running wet and run.
back analysis on wing,Display View,a Give name as view2 and click save. b Click Write Write Views panel will open,c Select view2 and click OK. d Type file name as view2 and click OK, c Contour of Volume fraction of Water Liquid eulerian on wing lower and. wing upper surface, Volume fraction contour shows where water particles are collected Now in the next stage we. will discuss about modeling of film using Stage 1 solution. Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Stage 2 Film Accretion, In this section film accretion is modeled through a UDF Secondary phase flux normal to the.
wall boundary removed at the walls where the film is modeled liquid film is formed from the. removed secondary phase,Step 1 Compile Read UDF, Go to Define User Defined Functions Compiled and change the Library name to. lib accretion Compile the UDF file film accretion c and then click Load. While the compiled library is being read in the list of all the UDFs in that library will be. printed on the Fluent console as shown in the above image In the subsequent sections these. UDFs will be hooked to the appropriate fields,Step 2 Cell Zone Conditions. Cell Zone Conditions,1 Set water liquid eulerian Phase. a Select Water liquid eulerian under Phase,b Click Edit. c Enable Source Terms,d Click Edit next to Mass,e Set Number of mass sources to 1.
f Select euler capture mass src,g Click OK, h Follow the same procedure to set momentum and energy sources. X Momentum euler capture x mom src,Y Momentum euler capture y mom src. Z Momentum euler capture z mom src,Energy euler capture heat src. Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Step 3 Models,1 Switch ON Eulerian Wall Film Model. Models Eulerian Wall Film Edit,a Enable Eulerian Wall Film Model.
b Enable Solve Momentum, c Select water liquid eulerian under Film Material. Note Film material should be always same as secondary phase material. d Go to Solution Method and Control Tab,e Set the Maximum Thickess as 0 01m. Note Choose Maximum Thickness such that during solution the film thickness never hits this. maximum limit If the film thickness value hits this limit then the solution will not be. appropriate,f Set the Time Step Size to 0 0001s,g Click OK to close the panel. Fig 2 Panel of Eulerian Wall Film Model, Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Step 4 Boundary Conditions,Boundary Conditionsl.
1 Enabling Film Modeling on the boundaries,a Select wing lower. b Select Mixture under Phase,c Click Edit,d Go to Wall Film Tab. e Enable Eulerian Wall Film,f Enable Initial Condition. g Make sure that all the parameters are set to Zero. h Click OK to close the panel, Fig 3 Panel of Eulerian Wall Film Boundary Condition. i Follow the same procedure to set Boundary Condition for wing upper. Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Step 5 Initialize the Wall Film Model.
Models Eulerian Wall Film Edit,a Go to Model Options and Setup tab. b Click Initialize,c Click OK to close the panel,Step 6 Enable Film Accretion. a Go to TUI,b Type enable film accretion t,c Press Enter. Step 7 Save the case,File Write Case,a Type the file name as airfoil step2 cas gz. Step 8 Run Calculation,Run Calculation,1 Set Run calculation parameters.
e Enter 200 for number of iterations,f Click Calculate. Step 9 Save the case and data file,File Write Case data. a Type the file name as airfoil step2 cas gz, Tutorial Collection efficiency calculation and running wet and run. back analysis on wing,Step 10 Post Processing,a Residual plot. Note For film solution there is no residual plot But the film solution can be monitored from. console by monitoring max cfl, Choose the film timestep such that max cfl does not go to very high value.
max cfl value less than 0 01 is reasonable but for some cases it can go up to 0 5. Tutorial Collection efficiency calculation and running wet and run back analysis on wing Introduction The first step in every aircraft icing analysis is to calculate the droplet collection impingement characteristics of the aircraft body under a given flight condition The parameter of interest in the analysis is the collection or catch efficiency This surface quantity represents the ratio