Tools

To study the effect of change in the flow rate and temperature on the heat transfer coefficient in a Shell & Tube heat exchanger

  1. Connect 15 ampere and 5 ampere plug pins to stable 230 V A.C. supply. Care should be taken to connect these two pins in different phases of the power supply.
  2. Connect the suction line of cold fluid circulation pump to cold water supply line. Adjust the cooling water flow rate to its maximum possible rate through the heat exchanger in order to make the cooling water side resistance to heat transfer negligible. Keep this flow rate of cooling water constant throughout the experiment.
  3. Ensure that the valve at the bottom of the glass section is open. Open the valve on the outlet line of the hot fluid tank. Start the hot fluid circulation pump and slowly increase the speed of the pump. Initially run the pump at slow speed. Check the inlet and outlet temperatures of the fluid indicated by digital thermometers. The error in the temperatures indicated by the inlet and the outlet sensors for hot and cold fluids respectively should be taken into account during calculations.
  4. Switch on the heater of the hot fluid tank.
  5. Adjust the flow rate of hot fluid through the heat exchanger by adjusting the speed of hot fluid circulation pump. Initially adjust the flow rate of hot fluid to about 5 - 6 cm3/s through the heat exchanger. Measure the flow rate by noting the time required for the hot fluid to attain the prescribed height in the glass section.
  6. Note down the inlet and outlet temperatures of hot as well as cold fluid indicated by digital thermometers on the control panel after steady state is reached.
  7. Repeat steps 5 and 6 for at least six different flow rates of hot fluid.