A rigid panel supports a vertical glass cylinder containing a horizontally mounted heating element immersed in the liquid. The heat input can be varied to control the heat flux and hence the mode of boiling.
At the top of the cylinder is a coil through which cooling water flows. This condenses the vapour produced by the heat input and the liquid formed returns to the bottom of the cylinder for re-evaporation. Control of the cooling water flow maintains a constant pressure during an experiment.
The standard instrumentation consists of a surface temperature thermocouple plus four glass thermometers, wattmeter, pressure gauge and water flowmeter. These enable all relevant heat transfer calculations to be made. For student safety, the unit is fitted with both overload and residual current circuit breakers. A high pressure cut out and internal safety valve prevents a safe pressure being exceeded. The heating element is protected by a high temperature switch.
