Cylinder Tank Cubic Meter calculation

Dear All,

I'm now working with CPU PLC Mitsubishi QO2U CPU. There have cylinder tank system that fill up with fuel from outside to inside cylinder tank. I've got assignment to display current volume of tank to human machine interface. To check level of fuel inside tank, I'm using Hart Level Transmitter (4~20mA).

Got problem to do programming ( find formula) to calculate current volume of petrol inside tank. If the tank installation to lay on the ground in vertical position, I think not big issue to calculate cubic meter of medium inside tank.

The problem is the tank in horizontal position.Any idea how to calculate current volume inside tank when tank in horizontal position?

High Tank : 300 meter
Diameter Tank : 30 meter
Cubic meter Tank: n(j)^2H = 3.142*15*15*300 = 212085 cubic meter

You get what I mean in this post?

The formula for volume of a liquid in a partially filled horizontal cylindrical tank with flat ends is

r = radius of the tank.
l = length of the tank.
h = height of liquid in the tank.

volume = l * (pi*r^2/2 - r^2*arcsin(1-h/r) - (r-h)*sqrt(h(2r-h)))

The formula computes the chord area of the circular cross section of the fluid at height h and then multiplies the cross section area by the tank length.


However, horizontal cylindrical tanks usually don't have flat ends, and they usually aren't exactly round, so simply using a formula can have significant discrepancies from the true amount of product in the tank. When high accuracy is needed it is more common to use a look up table that is customized to the particular tank.


There have been many discussions about measuring fluids in horizontal tanks on the forum. Do a forum search to see some of the threads where common problems and solutions are discussed.

This should help.

Thanks a lot for your reply.

I'll detail study about information that you all posting.

Thanks a lot.