TCPGB Film and Dropwise Condensation Unit

The Film and Dropwise Condensation Unit, "TCPGB", has been specially designed for students use and to provide visual results and quantitative results related to heat transfer during condensation.

Self-contained unit, which has its own steam generator and air extraction system, as well as condensers to provide dropwise and filmwise condensation.

Condensers:

• In film form: The condenser is made of natural copper with a built-in heat exchanger to preheat the cooling water. This serves to ensure that there is little variation in the temperature of the external copper face in which the vapour condenses. Three equally spaced thermocouples are fixed to the condenser. The cooling water inlet and outlet connections on the condenser are fitted with thermocouples for measuring the inlet and outlet water temperatures.
• In the form of drops: This is similar to the film-shaped condenser, except that the external surface of the condenser is gold plated to cause condensation in the form of drops.

The steam chamber is a thick-walled vertical glass cylinder, containing approximately 0.5 kg H2O, usually as saturated water and saturated steam.

The bottom plate carries an electrical heating resistance that converts water into steam at a rate determined by the input of electrical current. This steam circulates upwards towards the two condensers where it condenses by transferring the heat to the cooling water, and the condensed steam returns to the lower end of the chamber for re-evaporation. The water heating element is wound in a spiral and a control probe operates a thermostat which cuts off the action of the heating element in the event of overheating due to a shortage of water.

The chamber is equipped with three partitions to reduce the amount of splashes from the strong boiling.