Question

Laminar cross flow air enters an aligned tube bank. Converting the tube bank from an aligned arrangement into a staggered arrangement would _________ the heat transfer rate

A. increase
B. decrease
C. not change

Answer 1

The correct option is: A) increase. Converting the tube bank from an aligned arrangement to a staggered arrangement would increase the heat transfer rate. In contrast, an aligned arrangement allows the air to flow more smoothly, reducing the contact area with the tubes and limiting heat transfer.

Step-by-step explanation:

Converting the tube bank from an aligned arrangement to a staggered arrangement would increase the heat transfer rate. In a staggered arrangement, the tubes are positioned in a way that disrupts the laminar flow of the air. This disruption leads to increased turbulence, which in turn enhances heat transfer.

The irregular spacing in a staggered arrangement helps to break up the boundary layer and increase the contact between the air and the tubes, resulting in improved heat transfer. In contrast, an aligned arrangement allows the air to flow more smoothly, reducing the contact area with the tubes and limiting heat transfer.