Enter the flow rate, pressure, volume, and time into the calculator to determine the missing variable.

kPa → L/s (Orifice) Calculator

Enter ΔP (kPa), orifice Ø, Cd and density – or leave one blank to solve for it.

kPa
kg/m³
L/s
kPa ↔ L/s (Orifice) Conversion Table (d = 10 mm, Cd = 0.62, ρ = 1000 kg/m³)
kPa to L/s L/s to kPa
1 kPa = 0.0689 L/s0.05 L/s = 0.5272 kPa
2 kPa = 0.0974 L/s0.10 L/s = 2.1087 kPa
3 kPa = 0.1193 L/s0.15 L/s = 4.7445 kPa
5 kPa = 0.1540 L/s0.20 L/s = 8.4346 kPa
7 kPa = 0.1822 L/s0.25 L/s = 13.1791 kPa
10 kPa = 0.2178 L/s0.30 L/s = 18.9780 kPa
15 kPa = 0.2667 L/s0.35 L/s = 25.8311 kPa
20 kPa = 0.3080 L/s0.40 L/s = 33.7386 kPa
25 kPa = 0.3443 L/s0.50 L/s = 52.7165 kPa
30 kPa = 0.3772 L/s0.60 L/s = 75.9118 kPa
40 kPa = 0.4355 L/s0.75 L/s = 118.6122 kPa
50 kPa = 0.4869 L/s0.80 L/s = 134.9543 kPa
60 kPa = 0.5334 L/s0.90 L/s = 170.8016 kPa
75 kPa = 0.5964 L/s1.00 L/s = 210.8661 kPa
100 kPa = 0.6886 L/s1.25 L/s = 329.4784 kPa
125 kPa = 0.7699 L/s1.50 L/s = 474.4488 kPa
150 kPa = 0.8434 L/s1.75 L/s = 645.7776 kPa
200 kPa = 0.9739 L/s2.00 L/s = 843.4646 kPa
250 kPa = 1.0888 L/s2.50 L/s = 1317.9134 kPa
300 kPa = 1.1928 L/s3.00 L/s = 1897.7953 kPa
Formula: Q = Cd·A·√(2ΔP/ρ). This table assumes d = 10 mm, Cd = 0.62, ρ = 1000 kg/m³.

Kpa To Litres Per Second Formula

The following formula is used to calculate the flow rate in litres per second given the pressure, volume, and time.

Q = .0762Cv\sqrt(\delta*P)

Variables:

  • Q is the flow rate in litres per second
  • P is the pressure in kilopascals (Kpa)
  • Cv is the flow coefficient

To calculate the flow rate, multiply the pressure by the volume, and then divide the result by the time.

How to Calculate Flow Rate?

The following steps outline how to calculate the flow rate.

  1. First, determine the pressure (P) in kilopascals.
  2. Next, determine the volume (V) in litres.
  3. Next, determine the time (t) in seconds.
  4. Finally, calculate the flow rate using the formula Q = (P * V) / t.
  5. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Pressure (P) = 100 Kpa

Volume (V) = 50 litres

Time (t) = 10 seconds