CFD apparatus have ___________ valve actuators?

• A. Turn-wheel
• B. Hydraulic piston
• C. Electric motor
• D. Pneumatic

Answer: (A)

In basic CFD apparatus and hydraulics practice setups, valve flow is usually controlled by a hand-operated mechanism: a turn-wheel. This gives direct, immediate control of how open the valve is, which is ideal for experiments where you want to observe how small changes in opening affect pressure, flow rate, and the resulting fluid behavior. The turn-wheel is simple, reliable, and requires no power or plumbing connections, making it economical and safer for teaching and fundamental measurements.

Other actuators—electric motors, hydraulic pistons, or pneumatic cylinders—are used when automated or remote control is needed, or when large or fast changes in valve position are required. They add complexity, require power sources and fluids or compressed air, and are typically found in more advanced or industrial setups rather than in basic CFD practice equipment.