Quick update:
It turns out the way I calculated the annulus of the pipe was wrong.
This is how you determine Flow Rate, Flow Velocity, Pressure, and how much air can be added to the pipe.
The air pressure provided by the air pump needs to be higher than the current pressure in the pipe.
The air pressure can exceed the pressure already in the pipe to any degree, but the actual amount of air released by the diffuser must not exceed the L/min that would cause the water pump to go beyond it's pressure limit (Head height).
The number of L/min before the water pump reaches the pressure limit, can be discovered by converting the pumps total Head Height into bars. A percentage is then made of the pressure in the pipe (Without air being added) to the number of bars that the water pump is capable of.
Head Height to PSI conversion chart
The resulting percentage is then applied to the pumps Maximum Flow Rate, so it becomes the percent of the total L/min. By subtracting this from the total Flow Rate, the L/min that can be added to the pipe before the water pump reaches it's pressure limit, is made known.
Percentage Calculator.netThe pressure that will be in the pipe (Before air is added) is determined by the OD of the Air Stone / Diffuser, the ID of the pipe, and the total flow rate of the water pump. The gap between two circles, with one inside the other, is called an annulus. To find the pressure that will be in the pipe, we first need to make an imaginary pipe that has the same area as the annulus. To do this, enter the ID of the pipe into the top input (
R) of the suggested calculator and add the Diffusers OD into the bottom one (
r).
Area of Annulus CalculatorThen, enter the area of the annulus into the
Area input on the website below. This will give you the Diameter of the imaginary circle.
Circle CalculatorWith the Diameter of the circle and the total flow rate of the water pump known, the velocity of the water can be found by clicking
Velocity on
this calculator and then entering the Diameter of the imaginary pipe in millimeters and the max flow rate of the water pump into their respective text boxes. The
Meters Per Second number that results, needs to be applied to the
v - velocity (m/s, ft/s) input of this
Dynamic Pressure Calculator (Leave the ρ value at 1000). This will give you the pressure that will be in the pipe, which can be adjusted by altering the OD of the air diffuser and following through the calculation again.
What I need to know now is whether the max psi of a booster pump is combined with the first pump, or does it become the max psi of both systems?
Say the booster pump has a pressure rating of 2.75 bar.
Does the 0.60 bar of the first pump combine with the pressure of the booster pump, making 3.35 bar?
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