7/26/2011

Prism Meshing–Workshop 2 Wingbody

“Bottom up” Volume Meshing

First, extrude prism mesh from standalone surface mesh

-“Bottom up” approach

-Could also extrude into existing volume mesh (traditional method), “top down” approach

Generate rest of grid

-Farfield volume

-Delauney

Use density region

-Define mesh size for refinement

-In area where no geometry exists

Create Hexa core

-For majority hex fill in far field

Choose File > Open Project

-To load previously saved surface mesh and geometry

-Browse to Wingbody working directory

-Load previous project

If previous project was not completed, load the geometry F6_complete.tin and the mesh f6_surf.uns

Global Prism Parameters

Set global prism parameters

-Mesh > Global Mesh Setup > Prism Meshing Parameters

-Set Growth law to exponential (default)

-Initial height = 0

Height determined automatically so that last prism is similar volume to adjacent tetra

Proportional to size of triangle

-Height ratio = 1.2

-Number of layers = 5

-New volume part = LIVE

.Scroll down to access

.We will create prism from a surface-only mesh

.The volume part is necessary when extruding from surface mesh

Pick Parts for Prism Mesh

Select Parts and Compute prism mesh

-Mesh > Compute Mesh > Prism Mesh

-Press Select Parts for Prism Layer

.FAIRING, FUSELAGE, WING

-Apply, then Dismiss

-Compute

Height, height ratio, and num layers were set globally

Display Mesh

Display Prism mesh

-Turn off FARFIELD

-Zoom in to view prism quad faces on symmetry plane

-Turn on Mesh > Volumes > Prisms in model tree

-There is no other volume mesh but prisms

Unstructured mesh, prism.uns is saved automatically to the working directory

http://www.cadfamily.com/html/Article/Prism%20Meshing–Workshop%202%20Wingbody_718_1.htm

http://www.cadfamily.com/html/Article/Prism%20Meshing–Workshop%202%20Wingbody_718_2.htm

ICEM CFD Introductory Course-Prism Meshing

Inflation layers

-To better simulate boundary layer effects

-Mesh orthogonal to surface with faces perpendicular to boundary layer flow direction

Procedure

-Set Global Prism Parameters

-Select Parts to grow layers from

Typically wall boundaries

-Set Local Parameters for each part

.Local overrides global

.Zero or blank entries will defer to global settings

-Run mesher

.From existing mesh

-Extrude into tetra/hexa mesh

-Extrude from surface tri mesh, then fill volumes

.Run automatically during Volume Mesh creation

Prism - Global Parameters

Smooth Tetra/Prism Transition

Leave initial height as “0”

-This causes the initial height to float in order to reduce the volume change between the last prism and adjacent tetra.

Setting Prism Parameters on Parts

Setting Prism Parameters on Volume Parts

Normally toggle prism on only for parts that contain surfaces (becomes surface mesh)

Can also toggle on prism for parts that contain material points (becomes volume mesh)

-For interior surface mesh, this defines the allowable volumes for extrusion

-Selecting no volume parts has the same result as selecting all volume parts

Setting Prism Parameters on Surfaces

Setting Prism Parameters on Curves

-Mesh > Curve Mesh Setup

-You can get Prism to transition linearly across a surface by not setting a height on the surface, but instead set a different height on each curve on the opposite sides of the prism surface

-Height ratio and Num. of layers have no affect on prism for curve settings

http://www.cadfamily.com/html/Article/ICEM%20CFD%20Introductory%20Course-Prism%20Meshing_716_1.htm

http://www.cadfamily.com/html/Article/ICEM%20CFD%20Introductory%20Course-Prism%20Meshing_716_2.htm

http://www.cadfamily.com/html/Article/ICEM%20CFD%20Introductory%20Course-Prism%20Meshing_716_3.htm

Spring in UG_NX

 

figure1(final model)

Step1:Establish a new model,name spring.prt

Step2:Create helix as shown in figure 2

(1)Click ,curve ,helix,Popping the dialog box of "helix"

(2)Input the parameters like in figure 3,Click

figure 2 figure 3

Step3:Create sketch 1 as shown in figure 4

(1)Click ,,Popping the dialog box of "create sketch"

(2)Choose XC-ZC as sketch plane,click

(3)Create sketch as figure 5

(4)Click

figure 4 figure 5

Step4:Create sweep feature as shown in figure 6

figure 6

(1)Click ,sweep ,sweep along guide,Popping the dialog box of "sweep along guide"

(2)Choose sketch 1 as section,and choose the helix as guide.

http://www.cadfamily.com/html/Article/Spring%20in%20UG_NX_710_1.htm

Initiative Shaft in UG_NX

 

figure1(final model)

Step1:Establish a new model,name initiative_shaft.prt

Step2:Create revolve feature 1 as shown in figure 2

figure 2

(1)Click ,design feature,revolve.(or click the button of ),Popping the dialog box of "revolve"

(2)Click ,click and choose ZC-YC as plane,Click

(3)draw the figure 3 as follow.

(4)Click

(5)Choose YC as revolve axis

(6)Click

figure 3

Step3: Create the edge blend feature 1

(1)Click ,Click detail feature→Click edge blend (or click the button of ),Popping the dialog box of "edge blend"

(2)Click ,choose the line as select edge (as showed in figure

4)and radius 1 blank 2.

figure 4

(3)Click

Step4:Create extrude feature 1 as shown in figure 5

figure 5

(1)Click ,design feature,extrude.(or click the button of ),Popping the dialog box of "extrude"

(2)Click ,clickand choose the datum plane 1 as plane,Click

(3)draw the figure 6 as follow

(4)Click

figure 6

(5)In the start distance input -50,and in the end distance input 50.

(6)Click

Step5:Trim the body showed in figure 7

figure 7

(1)Click ,trim,trim body,Popping the dialog box of "trim body"

(2)Choose the body showed in figure 8,choose the surface showed in figure 9 as tool,click .

figure 8

figure 9

(3)Click

Step6:Create mirror feature 1 as shown in figure 10

(1)Click ,associative copy,mirror feature.Popping the dialog box of "mirror feature"

(2)Choose XC-YC as mirror plane,and choose the feature showed in figure 11 as mirror feature

figure 10 figure 11

(3)Click

Step7:Create hole feature 1 as shown in figure 12

figure 12

(1)Click ,design feature,hole.Popping the dialog box of "hole"

(2)Clickand choose the circle point as origin.

(3)Click

Step8:Create datum plane 1 as shown in figure 13

figure 13

(1)Click ,Popping the dialog box of "datum plane"

(2)In the field "type",choose "at distance" , choose ZC-XC as reference plane,at the field of offset input 70

(3)Click

Step9:Create extrude feature 2 as shown in figure 14

(1)Click ,design feature,extrude.(or click the button of ),Popping the dialog box of "extrude"

(2)Click ,clickand choose the datum plane 1 as plane,Click

(3)draw the figure 15 as follow

figure 14 figure 15

(4)Click

(5)In the value start distance input 0,and in the value of end distance input 12,in the field of boolean choose unite.

(6)Click

Step10:Create datum plane 2 as shown in figure 16

(1)Click ,Popping the dialog box of "datum plane"

(2)In the field "type",choose "at distance" , choose the plane showed in figure 17 as reference plane,at the field of offset input 20

http://www.cadfamily.com/html/Article/Initiative%20Shaft%20in%20UG_NX_715_1.htm