What is the friction loss in 400 feet of 3-inch hose with 2-1/2" couplings flowing at 400 gpm?

To determine the friction loss for a specific length of hose and flow rate, you can use the formula for calculating friction loss in fire hoses. Friction loss is influenced by the diameter of the hose, the flow rate, and the length of the hose.

In this case, you have 400 feet of 3-inch hose flowing at 400 gallons per minute (gpm). Generally, the friction loss in a 3-inch hose can be calculated using a standard formula or friction loss chart. For instance, a common rule of thumb provides an indication that friction loss in a 3-inch hose is approximately 1.5 psi per 100 feet at a flow rate around 400 gpm.

Using this method, for 400 feet of hose, you can calculate the friction loss as follows:

1. Determine the base friction loss for 100 feet: approximately 1.5 psi.

2. Multiply this base loss by the number of 100-foot sections in 400 feet (which is 4): 1.5 psi x 4 = 6 psi.

3. If we consider flow rate adjustments or specific friction loss coefficients for this particular flow rate, it may lead to a higher correction factor.

Ultimately, the final value when