Ansys Sw Instructions

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Problem Statement:Use ANSYS to determine the effect on water velocity that a submerged diverging diffuser duct has on.

Solidworks Instructions:Open Solidworks. To create a new file, select either the New (paper) icon at the top or select a New from the file menu.

Select the option for Part and click OK

Now that you are in the part editor, you need to set the units to inches. To do this, click the Options button.

This will bring up the options menu. To set the units you need to select the Document Properties tab, and click Units on the left hand menu. In the units section select the IPS option.

Click the Sketch Tab, and the Sketch button to start the drawing.

You now have the option to select the plane on which you will begin your drawing. Select the front plane.

Once selected, the Front Plane will be oriented so you have a view normal to its surface as shown below.

The first part that needs to be drawn is the profile of the Diverging Diffuser Duct. To begin the drawing, select the line tool.

Under the insert line window on the left side of the screen, select the options for For construction and Infinite Length.

*The Insert Line window is located in the blue rectangle. All editing options for dimensioning, extruding, cutting, revolving, etc. parts are shown in this location.

Select the first point at the origin, create a horizontal line.

Create a second Line above the first with the same properties (For construction and Infinite length)

Drawing the Diverging Diffuser Duct begins by drawing a line starting at the second construction line that was drawn.

We can dimension the line and then draw the rest of the ducts profile. To do this, we start by selecting the left hand point and making it vertically aligned with the origin, this is to ease plotting points in ANSYS later on. First select the leftmost point on the line, then, holding the control button, select the origin. With these two points selected, select the Vertical button under the Add Relations section of the Properties window. Vertical will appear under the Existing Relations section.

With this relationship in place, the line can be dimensioned with the dimension tool. Click the Smart Dimension button under the Sketch tab.

Add the following dimensions to the line.

Next we will complete the Duct geometry by creating an offset line, and adding two rounded edges to the duct. To offset the line, select the line and click the Offset Entities button. *Selecting an object in a sketch will turn it light blue.

Selecting the properties above will give you the image below.

Hit the Enter key or click the green check mark in the right hand corner.

This creates the offset. Next the two lines need to be connected. This is done using the Line Tool again. Select the Line Tool and click on an end point for one of the lines. Move the mouse away from the point and then return and over the mouse over the point again. This allows you to draw an arc starting at the point you selected. Connect the two lines with the circular arc as shown in the following images.

Repeat this process for the opposite side. Complete the Sketch by clicking the icon in the upper right-hand corner of the drawing screen.

The sketch should be fully defined at this point. If there is a (-) next to the sketch, check your dimensions. Next we will draw a rectangle using the Rectangle Tool. Create a second sketch on the Front Plane. This rectangle represents the cross section of the river.

Using Smart Dimension, dimension the rectangle as seen below.

This rectangle will serve as the water flowing in the river in ANSYS. Complete the Sketch. The next step is to turn the two drawings into a 3-d representation of the water in the river flowing through and around the diffuser. To do this we must first extrude the rectangle to create the water, and then perform a revolved cut using the drawing of the duct. This cut will create the volume of the duct in the river. Extruding the rectangle: 1. Select the sketch of the rectangle in either the side menu or from the drawing. 2. Once selected click the Features tab and select Extruded Boss/Base

3. In the Boss-Extrude window, enter 60 in the d1 space, and click the Reverse Direction button in the Direction 1 submenu. Hit enter or click the green check in the top right corner to complete the extrude.

4. Extruded the rectangle will take the shape of a grey box as seen above. The next step is to cut out the duct.

5. To do this, select the sketch of the duct cross-section and click the Revolved Cut button under the feature tab.

6. In the Cut-Revolve window, select the construction line that passes thorugh the origin for the Axis of Revolution. This will form the duct by revolving the drawing around this axis, and removing the material from the rectangle. a. Once in ANSYS, any solid in this drawing will represent the water in the river, while the area without any material represents the duct.

7. As before, click the Green Check-mark in the corner or hit enter. This completes the revolved cut. The Final product can be seen below in solid and wireframe views.

8. Now that the drawing is complete, save the file as diffuser_duct_8deg as a part file. This will allow you to easily modify the part in Solidworks is changes need to be made. 9. Click Save As and save the part as a STEP file.

ANSYS Instructions:Opening ANSYS:1. Loaction: C:\ANSYS Inc\v130\Framework\bin\Win64 2. Open RunWB2.exe

Starting Fluent:

1. This is the home screen for the ANSYS work bench. To start Fluent, drag the Fluid Flow (Fluent) from the Toolbox to the Project Schematic area.

2. Fluent will open inside of the Create standalone system box.

3. To start the process, right click on Geometry, go to Import Geometry and click Browse. Find the file that you saved as diffuser_duct_8deg.STEP and load it.

4. After loading the geometry, a check will appear next to the Geometry selection.

5. The next step is to Mesh the loaded geometry. Right-click on Mesh and select Edit.

6. This will open a the Meshing Utility in a new window.

7. Click on View and select Wireframe. This view will make the next few steps a bit easier.

8. Next we name each face in the model. a. To select a surface/face, make sure that the select Face button is pressed on the toolbar.

b. Left-click the top surface, right-click and select create Create Named Selection. Name this section Surface.

c. Select the opposite face and name that Floor.

d. Select the following surface and name it Outlet.

e. Select the surface opposite to this and name that Inlet.

f.

Select the face which the duct intersects and name this Symmetry Plane.

g. Select the side opposite to this and name it Wall.

h. The last named section is the Duct. You must select every surface of the duct for the simulation to work properly. Holding the Control key on the keyboard will allow you to select multiple surfaces in the model. Once all of the faces are selected, name the section Duct.

9. There should be a total of 7 named selections as seen below.

10. Next we will insert Inflation around the Duct. To do this right-click on Mesh in the Outline and go to Insert>Inflation.

11. Clicking this will open a subwindow in the Outline, this subwindow will allow us to set the inflation around the duct to capture the wall effects.

12. Select Geometry in this window, and make sure that the selection tool is on Body. This will allow you to select the entire model.

13. Click on the model and and click Apply on the geometry line and the selection will turn from green to purple.

14. Next, for Boundary Scoping Method, click on Geometry Selection and change it to Named Selections.

15. For Boundary, select Duct and hit enter. This sets where the Inflation will occur.

16. Leave the other parameters at their defailt values.

17. Click Generate Mesh to create the mesh.

18. Wait until meshing has finished. This window shows the status of the mesh.

19. In the Wireframe View, the mesh can be viewed as seen below.

20. Close the Meshing Utility.

Fluent Solution Set-Up1. Back at the main Workbench Screen, right-click Mesh and select Update.

2. Once the update has completed, right-click Setup and select Edit. This opens up the FluentLauncher. Keep the default settings and click OK to launch Fluent.

3. This is the Fluent main page. The rest of the analysis will be run from here.

4. Click General under Problem Setup.

5. Click Scale under the mesh screen, and change view View Length Unit In to inches.

6. Keep the other parameters the same. 7. Click on Models 8. Select Energy and click the Edit button.

9. Check the box next to Energy Equation to turn on the Energy Equation and click OK.

10. Select Viscous-Laminar and click Edit. 11. Select the k-epsilon (2-eqn) model and change the k-epsilon Model to Realizable, leaveeverything else the same and click OK.

12. Make sure the other Models are turned off (only Energy and Viscosity are on).

13. Select Materials under the Problem Setup section. Select air under Fluid in the Materialswindow and click Create/Edit.

14. In the Create/Edit Materials window, click on FLUENT Database select another fluid.

15. Select water-liquid(h2o) from the FLUENT Fluid Materials list and click Copy to add the fluidto the workbook and then click Close.

16. Click Change/Create in the Create/Edit Material and then click Close. 17. Select Cell Zone Conditions and select diverging_diffuser_8deg from the list of zones. ClickEdit.

18. The Fluid window opens. Change Material Name to water-liquid. Click OK and the window will close.

19. Click on Boundry Condidtions. a. Select Inlet and click Edit.

i. Change the Velocity Specification Method to Components, and change X-Velocity to 0.875 m/s. Make sure the Y-Velocity and Z-Velocity are 0, and the Initial pressure is 0. Leave everything else as-is. Click OK.

b. Select Floor and click Edit i. Set Wall Motion to Stationary Wall ii. Set Shear Condition to No Slip iii. Set Wall Roughness Values. 1. Roughness Height(in) = 0 2. Roughness Constant = 0.5

c. Keep the default values for Outlet d. For wall and surface set the following values: i. Wall Motion = Staitionary Wall ii. Shear Condition = Specified Shear 1. X-Component=Y-Component=Z-Component = 0 Pa iii. Roughness Height = 0 iv. Roughness Constant = 0

20. Select Solution Methods under Problem Setup. a. Set Scheme to SIMPLE b. Set the Spatial Discretization Parameters i. Gradient -> Least Squares Cell Based ii. Pressure -> Standard iii. Set Momentum, Turbulent Kinetic Energy, Turbulent Dissipation Rate, and Energy all to First Order Upwind

21. Select Solution Controls

a. Keep the Default Values of: i. Pressure = 0.3 ii. Density = 1 iii. Body Forces = 1 iv. Momentum = 0.7 v. Turbulent Kinetic Energy = 0.8 vi. Turbulent Dissipation Rate = 0.8 vii. Turbulent Viscosity = 1 viii. Energy = 1 22. Click Solution Initialization a. Select Standard Initialization if not already selected b. Select Inlet for Compute from c. Select Relative to Cell Zone for Reference Frame d. Click Initialize

23. Select Run Calculation

a. Set the Number of Iterations to 200 b. Keep Reporting Interval and Profile Update Interval at 1 c. Click Calculate

d. Wait 24. The simulation will continue to run until all of the Scaled Residuals reach the convergance limit. This is set at 0.001 by default. 25. After around 110 iterations, the solution will converge and the results can then be viewed.

26. There are several ways to view the results. a. Select Graphics and Animations . i. First is a Contour. Select Contours under Graphics and click Setup.

ii. Check Filled, and select Contours of Velocity, and X-Velocity. Select all of the surfaces. Click Display.

iii. Select Vectors next 1. Ensure that Global Range, Auto Range, and Auto Scale are all checked. 2. Select Vecotrs of: Velocity, and Color by: Velocity and X-Velocity 3. Choose Harpoon for Style, and change the Scale to 50 and leave Skip as 0. 4. Select symmetry_plane and duct under Surfaces and leave everything else off. 5. Click Display.

b. Select Plots i. Select XY Plot and click Set Up 1. Under Plot Direction, enter X=0, Y=1, Z=0 2. Select Velocity for the Y Axis Function, and select X-Velocity

3. Create a new surface by selecting the New Surface dropdown menu, and select Line/Rake. This wil be used to create a line in through the origin to measure the velocity at each depth at the position of the Inlet.

a. In the Line/Rake Surface window set the x and z values to zero, and set y0 = -32.74 and y1 = 15.26. Name the new

surface inlet-velocities amd click Create and close the window.

b. Back in the Solution XY Plot window, select inlet-velocities under Surfaces and click Plot.

27. This plot shows the water velocity at the inlet of the diffuser duct through the entire river on the symmetry plane. Notice the effect the river floor has on the velocity, and also note the substantial increase in the water velocity entering the duct.

Adding a Converging Hydrfoil to the front of the duct:Go to

http://www.ppart.de/aerodynamics/profiles/NACA4.html

Click show points. Copy and paste points into excel

Highlight row A, select data tab and click text-to-column button.

Select delineated (default) and click next.

Select space and click next.

Click finish. Data should now be sorted into columns A and B.

Enter zeros into column 3 for the same length as A and B.

Highlight column A,B and C and right click and select format cells. Choose number and select 6 decimal points and click OK.

Highlight rows A,B and C and copy and paste into a notepad file and save as a text file.

Open Solid works and create a new part file

Change units to inch/pound/s

Go to insert-curve-curve through xyz points

Click brows and select the airfoil text file and click open.

Click Ok

Click the sketch tab then the sketch button and select the front plane.

Click the covert entities and select the curve and click OK.

Go to tools-sketch tools-scale and select the curve select the origin for scale about and choose a scale value of 6. This will scale the curve from 1in to 6in.

Go to tools-sketch tools-rotate

Select the curve, choose the origin for rotate about, and input -12 degrees for angle of rotation. This will give a 10 degree angle of attack.

Double click the curve and click fix to fully define the curve.

Follow previous instructions for extruding and creating a solid region but remember to connect the right end of the hydrofoil to the front-end of the duct.

Warning: Errors like thse frequently pop up during normal operation.