BACK PRESSURE REGULATOR

A back pressure regulator ("BPR") includes a pressure housing that at least partially defines a flow chamber that the liquid flows through and the BPR has an adjustable restriction that varies with the flow rate to maintain an upstream liquid pressure. The pressure housing is contoured to distribute the liquid flow to provide radial flow into the adjustable restriction from circumferentially about the adjustable restriction. The pressure housing includes ramped and curved side passages that guide the flow and ridges that divide the flow and prevent internal collisions between the flow. A flow deflector extends into the chamber outlet to prevent the radial flows through the annular restriction from colliding. The flow deflector redirects the flows to smoothly recombine in the chamber outlet.