Sizing a bypass around a closed isolation valve
Working on what seems like hydraulics problem out of a college textbook. Would appreciate some input from fellow water engineers.
An existing 24-inch steel bypass line is used to fill a gravity-fed transmission line downstream of a closed 108-inch isolation valve. The bypass flow rate is constrained by the 108-inch downstream pipe’s max AWWA recommend fill velocity of 1 fps to avoid downstream transient pressure. The existing bypass flow control valve is regulated to a maximum of 19,000 gpm via an orifice plate.
The upstream pressure is around 280 psi and will remain constant throughout the filling. Assuming the bypass stays open until the downstream back pressure is around 175 psi, what is the maximum bypass velocity and diameter considering effects from cavitation and vibration?
Mostly interested in the effects of cavitation and vibration and how will affect design. And whether there is any technical guidance out there to follow. TIA.