Interactive spreadsheet and graphs of the Windtunnel results

[74_5.0L_Z]

From the snapshot of the aerodynamic results and some basic aerodynamic relationships I was able to reverse engineer all of the lift, and horsepower numbers from the coefficients and vice versa. After I was sure that I had established relationships based in physics that work for all the data, I built a spreadsheet that allows the user to vary the velocity, air density and frontal area and see how it affects all of the test cases.

 

The relationships that I used to go back and forth between the coefficients and the forces are as follows:

 

CL=L / (1/2 x rho x V^2 x A)

CD=D / (1/2 x rho x V^2 x A)

Cs=S / (1/2 x rho x V^2 x A)

CPM=M / (1/2 x rho x V^2 x A x WB) where M = (Lf - Lr) x WB/2

 

HP = D x V

 

From the data given, I don't have enough information to calculate CYM, CRM and Q(psf). These bits of data would be nice, but they are almost inconsequential to the tests that were performed.

 

The data and graphs are in an excel file that includes an interactive graph. By that I mean that you can select the data that appears on the graph through the use of some dropdown menus. In order for this feature to work properly, you must set your Excel Macro security to medium and allow the application to run the macros.

 

If you don't know the current level of your Excel Macro security, set it to medium as follows:

 

From Excel

Select Tools -> Macros -> security and select medium.

 

Do this before trying to run the new spreadsheet.

 

I will gladly accept any feedback for improving this tool and will respond to correct any errors that anyone discovers.

 

Here is the link to the file. It is compressed as a .rar file which is like a .zip file.

http://forums.hybridz.org/attachment.php?attachmentid=2961&d=1181700792

 

The following link is to an application that will open the .rar file.

Download winrar

 

http://www.download.com/WinRAR/3000-...ml?tag=lst-0-2

 

 

I originally posted this elsewhere but the spreadsheet was buried in the middle of the thread with various pertinant info spread throughout. I felt that it would be more visible and convenient if I started a new thread.

[Carl Beck]

Q is the dynamic pressure, 0.5*density*V^2. If the testing were at 80 mph (=117.3 ft/s), at "standard" conditions Q comes out to 16.3 Lbf/ft^2, in the usual engineering units.

 

Cross-sectional area times Q times the drag (or lift, etc.) coefficient gives the drag (or lift, etc.) force.

 

I really regret that I didn't participate in your wind tunnel test....

 

Thought I'd re-Post Michels answer here, since a new thread more specific to the Spreadsheet was started.

 

Thanks for all the work on this 74_5.0L-Z

 

regards,

Carl B.

"a jumper wire around the power supply switch" - - what do you expect for $20 Billion Dollars!! Must be some HybridZ guys up there....