### Pressure drop answer compare to Darcy Weisbach

Posted:

**Wed Sep 26, 2018 10:43 pm**I performed a pressure drop calculation in the flow calculator and compared the result to another spreadsheet that uses the Darcy-Weisbach equation for pressure drop - the results did not match. I double check the spreadsheet equation and calculations by hand and it appears to be correct.

The Darcy-Weisbach is simplified by assuming laminar flow and using viscosity ( delta p / L = (128 / pi) - uQ /D^4)

Since the parameters in the program indicated the flow regime was Laminar I expected the results to match. Can you let me know why the results would be different? What underlying equation are involved that cause the result to be different.

I am not sure how to include a screen shot from the program with parameters and results, so let me know if you need more information.

Regards,

Sean

The Darcy-Weisbach is simplified by assuming laminar flow and using viscosity ( delta p / L = (128 / pi) - uQ /D^4)

Since the parameters in the program indicated the flow regime was Laminar I expected the results to match. Can you let me know why the results would be different? What underlying equation are involved that cause the result to be different.

I am not sure how to include a screen shot from the program with parameters and results, so let me know if you need more information.

Regards,

Sean