Final answer:
The 180-degree bend in the inlet of the Penberthy siphon ejector creates a pressure drop to initiate fluid flow and prevents direct contact between siphoning and motive fluids.
Step-by-step explanation:
The 180-degree bend in the inlet of the Penberthy siphon ejector serves a specific purpose in its operation. The design of the bend creates a pressure drop that helps to initiate the flow of fluid through the ejector. This pressure drop occurs due to the change in direction of the fluid flow, causing a decrease in velocity, which in turn creates a suction effect.
When the fluid enters the bend, it experiences a change in direction and a resultant centripetal force. This force creates a pressure difference along the bend, with the outside of the bend experiencing a higher pressure than the inside. This pressure difference is what initiates the flow of fluid through the ejector.
Additionally, the 180-degree bend helps to prevent any direct line of sight between the siphoning fluid and the motive fluid. This separation is important to avoid any possible contamination or interference between the two fluids.