You can use pressure drop in pipe calculator for pressure drop and flow rate calculation for all
Newtonian fluids (gases and liquids) with constant density (incompressible flow) in closed, round or rectangle pipe.
Pressure drop calculator is suitable for laminar and turbulent flow regime.
You can't use this calculator for compressible gas flow where the pressure of the gas is changing
more than 5-10%. For that purpose, you can use one of available gas pressure drop calculators.

Select a subscription plan and enable the full service:

- Switch between metric and imperial units in one click
- Export calculation results in Word .docx or Excel .xlsx format
- Preview results on one place and copy/paste it in your favorite text editor
- Send results back to your email
- Support the future of this project

And even more... Subscribed users have access to the full set of 19 calculators available as Java™ Web start application or download Windows™ 64bit application.

Total cost for one month

$995/month

PreDropWaterQ, D, L, kr, Δp

Task:
Calculate pressure drop in round pipe with flow of 5 m^{3}/h,
pipe length 100 m, internal pipe diameter of 25 mm and pipe roughness of 0.1 mm.
Flowing fluid is water with density of 1000 kg/m^{3}.
Local resistance can be negligible K = 0.

Solution: Pressure drop is: 4.78 bar

PreDropWaterΔp, D, L, krQ

Task: Calculate flow rate of water through closed round pipe with internal diameter of 25 mm, pipe length of 100 m. Pipe line connecting reservoir on the elevation of 20 m above the pipe exit with water flowing to open atmosphere. Reservoir is under atmospheric pressure. Pipe roughness is 0.1 mm.

Solution: Flow rate is: 3.16 m3/h

PreDropAirQ, H, W, L, krΔp

Task:
Calculate pressure drop of 2000 m^{3}/h of air flowing through closed
rectangle chanel to open atmosphere. Chanel width is 400 mm and height is 250 mm.
Chanel is with surface roughness of 0.01 mm. Local resistance coefficient is line is 3.5.
Chanel length is 85 m.

Solution: Pressure drop is: 298.96 Pa