A 2inch diameter pipe has been chosen to pass 65 GPM. Can this diameter be used for the suction line? If not , what line diameter should be specified?
To determine whether the 2-inch diameter pipe can be used for the suction line, we need to check whether it can handle the flow rate of 65 GPM while maintaining an acceptable fluid velocity.
First, let's calculate the flow velocity through the pipe.
Step 1: Convert the pipe diameter into feet. Since we know the pipe has a 2-inch diameter, we'll divide it by 12 to convert it to feet.
2 inches / 12 = 0.167 feet
Step 2: Calculate the area of the pipe. We'll use the formula for the area of a circle: A = π * (r^2), where r is the radius of the pipe.
radius (r) = diameter / 2 = 0.167 / 2 = 0.0835 feet
area (A) = π * (0.0835^2) = 0.0218 square feet
Step 3: Calculate the velocity using the flow rate (Q) and the pipe area (A).
velocity (V) = flow rate (Q) / area (A)
V = 65 GPM / 0.0218 square feet
Now, let's convert GPM to cubic feet per second (CFS) because it is a more commonly used unit for velocity calculations.
1 GPM = 0.002230 CFS (approximately)
65 GPM = 65 * 0.002230 CFS = 0.14495 CFS
Finally, calculate the velocity:
V = 0.14495 CFS / 0.0218 square feet
V ≈ 6.65 ft/s (approximately)
The typical recommendation for the velocity in a suction line is to keep it between 2 to 6 ft/s. Since our calculated velocity is around 6.65 ft/s, it exceeds the upper limit. Therefore, the 2-inch diameter pipe cannot be used for the suction line.
To determine the appropriate line diameter, we need to calculate the velocity for different diameters and choose one that falls within the recommended range.
Here are the steps to determine the proper line diameter:
1. Start with a smaller diameter and calculate the velocity using the same steps as before.
2. Keep increasing the diameter gradually until the velocity falls within the recommended range of 2 to 6 ft/s.
Repeat the above steps for different diameter sizes until you find one that gives an acceptable velocity within the desired range.