I'm designing a small system where typically a ball valve is used to divert water through a heater when desired. I've noticed the ball valves designed for this situation result in a hard 90 degree turn when diverting the flow, and also lowers the diameter of the pipe by approximately 10%. The inside of the valve is manufactured such that it will create a significant amount of friction and turbulence even when it's in the straight/bypass position.
I'm considering an alternate plumbing approach that uses a standard ball valve and tee wye bend fitting. When the ball valve is closed, water will be diverted through the tee wye bend. I suspect this will result in less resistance and higher flow than the aforementioned three way valve will allow, but I'm unsure if I need to be worried about turbulence or other factors that will constrain flow while the system is in either of the two possible states.
The valve will be open to bypass the heater the majority of the time. Will the tee branch lead to a significant amount of friction or turbulence that will impede the flow in any considerable amount?
Can someone with a better understanding of the fluid dynamics at play here verify that my alternate approach is more efficient (or at least not significantly less efficient) in terms of flow than the design with the three way valve?