Solve the following problem:
Q: A novel heat exchanger concept consists of a large number of extruded polypropylene sheets (k = 0.17 W/m · K), each having a fin-like geometry, that are subsequently stacked and melted together to form the heat exchanger core. Besides being inexpensive, the heat exchanger can be easily recycled at the end of its life. Carbon dioxide at a mean temperature of 10oC and pressure of 2 atm flows in the cool channels at a mean velocity of Um = 0.1 m/s. Air at 30°C and 2 atm flows at 0.2 m/s in the warm channels. Neglecting the thermal contact resistance at the welded interface, determine the product of the overall heat transfer coefficient and heat transfer area, UA, for a heat exchanger core consisting of 200 cool channels and 200 warm channels.
