SL 220 Flow Boiling Demonstration teaching aid equipment Hydrodynamics Experiment Apparatus
Heating a liquid over a heating surface produces different modes of boiling dependent on the heat flux density. They can accelerate the evaporation process (nucleate boiling) or impair it (film boiling). In practice, a limitation of the heat flux density must be assured in order to prevent damage to the heating surface. This knowledge is applied in practice e.g. when designing steam boilers for steam-powered drives.
The SL 220 experimental unit can be used to demonstrate boiling and evaporation processes in a straightforward manner. The processes take place in a transparent tank. A condenser in the form of a water-cooled tube coil ensures a closed circuit within the tank.
R1233zd is used as evaporating liquid. Compared with water, this liquid has the advantage that its boiling point is at approx. 18°C (1013hPa), whereby the evaporation process takes place at much lower temperatures and a lower heating power.
Sensors record the flow rate of the cooling water, the heating power, pressure and temperatures at all relevant points. The measured values can be read on digital displays. At the same time, the measured values can also be transmitted directly to a PC via USB.
visualisation of boiling and evaporation in a transparent pressure vessel
evaporation with heating element
condensation with tube coil
safety valve protects against overpressure in the system
pressure switch for additional protection of the pressure vessel, adjustable
sensors for pressure, flow rate and temperature with digital display
refrigerant R1233zd, GWP: 1
III. Technical Data
power: 250W, continuously adjustable
Safety valve: 2bar rel.
Pressure vessel: 2850mL
Condenser: coiled tube made of copper
filling volume: 1,2kg
pressure: 0…4bar abs. (tank)
power: 0…300W (heater)
flow rate: 0,05…1,8L/min (cooling water)
temperature: 4x 0…100°C
230V, 50Hz, 1 phase
230V, 60Hz, 1 phase
120V, 60Hz, 1 phase