What is the equivalent length of a three-quarter tee if the direction of flow changes?

The correct answer reflects the concept of equivalent length, which is an essential factor in understanding flow resistance in piping systems. When the direction of flow changes through a fitting such as a three-quarter tee, there is a certain amount of energy loss due to friction and turbulence created by that change in direction.

In this context, a three-quarter tee is considered to create a significant equivalent length because it forces fluid to navigate through a 90-degree turn. The value of 4 feet is an established standard figure that accounts for the frictional losses associated with the fitting when designing a system. This length is added to the total length of the piping when calculating pressure drop or flow rates, ensuring that systems are properly designed for efficiency.

Understanding equivalent lengths is crucial for technicians and engineers as it allows for more accurate calculations in fluid dynamics and ultimately leads to better operational performance of gas systems in commercial food equipment settings.