Reference no: EM132293253

Lab Assignment - Heat Exchanger Systems

Objectives -

The general aim of this practical is to demonstrate indirect heating or cooling of heat from one fluid stream to another when separated by a solid was and to perform energy balance across shell and tube, concentric and plate heat exchangers. The practical will also demonstrate the effect of hot and cold fluid flow rates on thermal efficiency and overall heat transfer coefficient of the three heat exchangers.

Experiment 1 - Demonstration of indirect heating of cooling by transfer of heat from one fluid stream to another when separated in a solid wall (fluid to fluid heat transfer)

The following procedure demonstrates heat transfer from one fluid stream to another when separated by a solid wall.

Note that the observations from Experiment 2 may be used for the calculations in this procedure in order to save experimental time.

Procedure -

Install the Concentric Heat Exchanger H101A and connect the cold water circuit to give Counter-Current flow as shown in Figures 1 and 2 (Attached).

Set up according to the following operating conditions:

Turn on the 'MAIN SWITCH' and 'HEATER' SWITCH'.

Set the hot water controller to 60^oC.

Set the cold water flow rate V_cold to 15 g/sec.

Set the hot water flow rate V_hot to 50 g/sec.

Monitor the stream temperatures and the hot and cold flow rates to ensure these too remain close to the original setting. Then record the following:

T₁, T₂, T₃, T₄, V_hot, and V_cold.

Then adjust the 'COOLING WATER FLOW CONTROL' so that V_cold is approximately 35 g/sec. Maintain the Hot water flow rate at approximately 50 g/sec (the original setting).

Allow the conditions to stabilise and repeat the above observations.

The procedure may be repeated with different hot and cold flow rates and different hot water inlet temperature if required.

Experiment 2 - To perform an energy balance across a concentric tube heat exchanger and calculate the overall efficiency at different fluid flow rates.

The following procedure demonstrates heat transfer from one fluid stream to another when separated by a solid wall and shows that the heat release rate of the hot stream should equal the heat absorption rate of the cold stream, plus any incidental losses or gains.

NOTE that the observations from experiment No 1 may be used for the calculations in this procedure in order to lease experimental time.

Procedure -

Using the Concentric Heat Exchanger H101A installed in Experiment 1, make sure the cold water is connected to Counter-Current flow as detailed in the same section.

Set up according to the following operating conditions:

Turn on the 'MAIN SWITCH' and 'HEATER SWITCH'.

Set the hot water temperature controller to 60^oC.

Set the cold water flow rate V_cold to 15 g/sec.

Set the hot water flow rate V_hot to 50 g/sec.

Monitor the stream temperatures and the hot and cold flow rates to ensure these too remains close to the original setting. Then record the following:

T1, T2, T3, T4, T5, T6, V_cold and V_hot.

Then adjust the 'COOLING WAVER FLOW CONTROL' so that V_cold is approximately 35g/sec. Maintain the Hot water flow rate at approximately 50 g/sec (the original setting).

Allow the conditions to stabilise and repeat the above observations.

The procedure may be repeated with different hot and cold flow rates and different hot water inlet temperature if required.

Attachment:- Assignment Files.rar