High order panel modeling units?

In summary, the conversation discusses the use of Pan Air (A502), a panel method for modeling 3D airflow around objects. The units used in the program are unclear, as the free stream velocity is normalized and there is no place to enter air density. The question is how to rescale the coefficients to account for these factors. One person suggests that the coefficients are meant to be non-dimensional and easily scaled, but the other person argues that the program may need to be scaled by both the free stream velocity and dynamic pressure. However, there is no method described in the manual for doing this.
  • #1
Ryoko
114
5
I have a copy of Pan Air (A502) which is a high-order panel method used for modeling 3D airflow around arbitrary bodies. I've read the manual, but I'm not clear about the units used. As I understand it, the free stream velocity is normalized which implies that all the other geometry is scaled by the same factor used to normalize the free stream velocity to a unit vector. No problem with that. But this is going to affect all the various factors it solves for, namely Cl, Cd, Cm, Cdi, and so on. There's also no place to enter the air density. So my question is how do I rescale the various coefficients to restore the units and take density into account?
 
Engineering news on Phys.org
  • #2
I am not familiar with that software, but the whole point of the force and moment coefficients is that they are supposed to be nondimensional and allow easy scaling of their respective quantities for a given set of dimensional conditions. Why do you feel you need to rescale them somehow?
 
  • #3
I understand that the coefficients are technically non-dimensional. But the program asks for things like span and area which is causing the reported numbers to change dramatically. It's pretty clear it's deriving the coefficients by dividing the forces by the area & span as needed, but the dimensions you need to give it is not clear. Plus, none of the input parameters reflect the dynamic pressure.

It seems the model needs to be scaled by both the free stream velocity and by Q. However, no method is described in manual for doing this.
 

FAQ: High order panel modeling units?

What is a high order panel modeling unit?

A high order panel modeling unit is a statistical method used in social science research to analyze and understand complex relationships between variables. It involves creating a multi-level structure of data, with individual observations nested within larger units (such as households, neighborhoods, or organizations).

How is a high order panel modeling unit different from other statistical methods?

Unlike traditional statistical methods, a high order panel modeling unit allows for the examination of relationships at multiple levels of analysis, rather than just the individual level. It also takes into account the nested nature of data, which can lead to more accurate and nuanced results.

When is a high order panel modeling unit used?

A high order panel modeling unit is commonly used in social science research, particularly in fields such as sociology, psychology, and economics. It is useful when studying complex social phenomena that involve multiple levels of analysis and when the data is hierarchically structured.

What are the benefits of using a high order panel modeling unit?

One of the main benefits of using a high order panel modeling unit is its ability to account for the complex relationships between variables at different levels. It also allows for the examination of time-varying effects, as well as the testing of hypotheses at different levels of analysis. Additionally, it can help researchers avoid making incorrect inferences due to the nesting of data.

What are some common challenges in using a high order panel modeling unit?

One challenge in using a high order panel modeling unit is the potential for model complexity, which can make interpretation and communication of results more difficult. Additionally, it may require a larger sample size to accurately estimate the parameters. Finally, there may be issues with missing data or unequal panel lengths, which can affect the validity of the results.

Similar threads

Replies
20
Views
8K
Replies
3
Views
2K
Replies
1
Views
3K
Replies
7
Views
4K
Replies
5
Views
29K
Replies
1
Views
3K
Replies
21
Views
11K
Back
Top