How to apply pressure field in Nastran 2

[harshitbhatt]

I have a excel sheet in which there is radius and pressure acting on radius. I have divided the radius in small parts and each part has pressure acting on it. The pressure is like increasing from low to high. Its not uniform.So at every new node new pressure.

I need to apply the pressure on my model in NX. How to do so.Please help me

 

[Zadrobu]

In your Nastran model you need to have a PLOADx card for every possible pressure value. Then every loaded element needs to be assigned to one of the PLOADx cards.

Fortunately it's not necessary to do all this manually. Your preprocessor software is sure to have an option for defining pressure fields. Such an option lets you select the loaded elements and a values table (or equation) that defines the pressure field. Subsequently the preprocessor takes care of generating the correct PLOADx cards for Nastran.

 

[harshitbhatt]

@Zadrobu thank you for the reply sir. I have a excel sheet and there are nearly 2000 pressure values. How to do that.

 

[Zadrobu]

@Zadrobu thank you for the reply sir. I have a excel sheet and there are nearly 2000 pressure values. How to do that.

The exact steps depend on which preprocessor program you're using (e.g. Patran, Hyperworks, Femap, or other). Look in the help documentation of the program that you're using for pressure definition options. If you're still stuck afterwards, then post the question on another forum that is dedicated to your preprocessor program.

 

[Tuw]

Hi,

If you are using NX as the preprocessor, then click on the pressure load icon.

In the pressure dialog box, click on the circled location to launch a table input.

At here, you have tonnes of option to input the tabular data. My suggestion is you need to create a new local cylindrical coordinate system in your simulation model, which is referring to your excel data. Based on this reference, choose Domain as Cylindrical, and input your excel data in the form of radius, theta, and z, which is referring to the local cylindrical coordinate you have created earlier.

Also in NX, we have the button to sync excel data, edit the data to NX from excel. Hope this helps.

Regards,
Tuw

 

[harshitbhatt]

@Tuw I have no option as in your picture sir. I am getting only this.

I tried to import excel sheet also but its not working.Nothing happens.All the field remain blank.I choosed independent of time.

 

[Tuw]

Hi,

You will need to choose spatial from the pressure drop down list.

Regards,
Tuw

 

[harshitbhatt]

@Tuw thanx for the reply sir.Wen I enter the data in excel sheet and save it and than close it,nothing enters in the nx table.And I need to have for one radius multiple degrees and each degree has pressure.

For example lets say I have 46 mm radius and I divided it in 14 degrees and every degree has pressure. I added the photo of it. In picture 46 is the radius and 0-14 are degrees and pressure for each degree.

 

[Tuw]

When you click the Excel button in NX that automatically launch Excel, you should see the pre-defined column title as picture below. Also, noticed that at the Add-ins Tab in Excel, that is an extra button called Update Table. Press that button, in order to transfer your excel data to NX.

For each data, you need radius, theta, and Z input. So input your sets of values in Excel. And take note, this data set is referring to the cylindrical coordinate system that you defined in NX earlier.

Regards,
Tuw

 

[harshitbhatt]

@Tuw thanx for the reply sir but I need to enter multiple value of theta [0-14] and pressure for single radius.Is that possible in this table?

The values that I posted in the above post as screenshot.

 

[Tuw]

Possible. For example, input each sets as below:

(same radius, theta1, Z1)
(same radius, theta2, Z2)

Tuw

 

[harshitbhatt]

@Tuw sir thanx for the reply sir.I did the same but I am getting confused what value to add in Z as I have no data regarding Z. Right now I added 0.