Which arrangement is described as counter flow in a water coil?

Which arrangement is described as counter flow in a water coil?

• A. Parallel flow
• B. Cross flow
• C. Counter flow
• D. None of the above

Answer: (C)

Counter flow is when the two fluids exchange heat while moving in opposite directions along the length of the exchanger. In a water coil, that means the water inside the tubes flows in one direction while the air flowing over the coil travels in the opposite direction along the coil. This opposite flow keeps the temperature difference between the two streams relatively large throughout the coil, which boosts heat transfer more than when the streams move in the same direction (parallel) or at right angles (crossflow). So, the arrangement described as counter flow is water moving in one direction and air moving in the opposite direction along the coil.

Counter flow is when the two fluids exchange heat while moving in opposite directions along the length of the exchanger. In a water coil, that means the water inside the tubes flows in one direction while the air flowing over the coil travels in the opposite direction along the coil. This opposite flow keeps the temperature difference between the two streams relatively large throughout the coil, which boosts heat transfer more than when the streams move in the same direction (parallel) or at right angles (crossflow). So, the arrangement described as counter flow is water moving in one direction and air moving in the opposite direction along the coil.