This is a highly advanced concentric tube heat exchanger with hot water flowing through the central tube while cooling water flows through the annular space.
The heat exchanger has been divided into three equal sections in order to allow examination of the intermediate stream temperature conditions and temperature distribution through the heat exchanger.
Thermocouples sense the hot and cold stream temperatures at the four stations and the inner tube wall temperatures on entry and exit.
The addition of the central tube surface temperatures at inlet and exit allow detailed investigation of the surface heat transfer coefficient inside and outside the central tube.
This allows advanced students to investigate the Nusselt, Reynolds, Prandtl relationship
Nu = k Rea Prb.
The core tube temperatures also allow students to plot hot stream, cold stream and core tube temperatures for both con-current and counter-current flow.
The unit incorporates an extended range flowmeter in order to allow investigation of low and high range Reynolds numbers.
The PID temperature control on the H102 Heat Exchanger Service Unit allows investigation of turbulent flow conditions at a range of fixed Prandtl numbers.
Investigations using these two methods of control allow students to experimentally determine the constants in one of the classic empirical equations for turbulent heat transfer in a tube.
Nu = 0.023 Re0.8 Pr0.4
