How to calculate water from storage tank to small tank?

[karloon]

I have a 10,000L water tank (size 3.5m Dia x 1.0 m H) connected to 2 inch pipe (bottom of the tank). How do I calculate the speed/volume of the water flow out from the tank?

 

[rock.freak667]

You could use Torcelli's formula (from conservation of energy) to get v=√(2gh)

and then if you wanted the flow rate you'd use Q=Av where A = cross-sectional area of the pipe.

 

[karloon]

Thank You rock.freak667,

I checked the Torcelli's formula and it helps. However, using this formula. Can I calculate the water flow if it involve more that 1 tank?

For example:
I have "THREE" 10,000L water tank (size 3.5m Dia x 1.0 m H), each connected to 2 inch pipe (bottom of the tank) and share the same main drain pipe (6 inch). All three tank will flow from the 2" pipe to 6" main drain pipe and finally enter a storage tank. Will the flow/speed still be the same and I just change the Q=Av (A- from 2" pipe to 6" pipe) for the water flow?

TQ in advance.

 

[rock.freak667]

If you want the water flow for the 6" drain pipe then you'd have to add the flows together I believe.

However I could be wrong as I've not done fluid related problems in for a few years.

 

[PJC01]

To calculate the speed and volume of water flowing out from the storage tank to the small tank, you will need to consider several factors such as the diameter of the pipe, the height of the water column, and the pressure within the tank.

First, you will need to determine the cross-sectional area of the 2-inch pipe. This can be calculated using the formula A = πr^2, where A is the cross-sectional area and r is the radius of the pipe. In this case, the radius would be 1 inch or 0.0254 meters, giving a cross-sectional area of approximately 0.000506 square meters.

Next, you will need to calculate the height of the water column in the tank. This can be done by dividing the volume of water in the tank (10,000L or 10 cubic meters) by the cross-sectional area of the tank (3.5m x 1.0m or 3.5 square meters), giving a height of approximately 2.86 meters.

Using the height of the water column and the cross-sectional area of the pipe, you can now calculate the speed of the water flow using the Bernoulli's equation, which states that the speed of a fluid is equal to the square root of 2gh, where g is the acceleration due to gravity (9.8 m/s^2) and h is the height of the water column. Plugging in the values, the speed of the water flow would be approximately 5.41 m/s.

To calculate the volume of water flowing out per unit of time, you can multiply the cross-sectional area of the pipe by the speed of the water flow. In this case, it would be 0.000506 m^2 x 5.41 m/s = 0.00274 cubic meters per second.

However, it is important to note that these calculations are based on ideal conditions and do not take into account factors such as friction and turbulence in the pipe, which may affect the actual flow rate. It is recommended to conduct actual flow rate measurements to get a more accurate result.