H411 Flow Boiling Demonstration Unit

H411 Flow Boiling Demonstration Unit

The H411 is a floor-mounted unit designed to provide a visual demonstration of the flow boiling processes that can occur inside the vapour generating tubes of practical plant such as refrigeration, steam, chemical and food processing systems.

A real (not simulated) boiling process is used and all the stages of evaporation from warming of sub-cooled liquid to nucleation, bubble flow, slugging, annular flow, droplet entrainment and finally superheated vapour can be observed and demonstrated. The unit operates under steady state conditions allowing the processes to be studied for prolonged periods of time.

H411 Flow Boiling Demonstration Unit

Floor mounted, vertical, glass, concentric tube heat exchanger for the observation of all stages of heat transfer as a pure substance changes from sub-cooled liquid to superheated vapour.

Demonstration of a heating process accompanied by vapour formation within

Within a tube, including

  • Circulation promoted by natural convection
  • Convective heat transfer to sub-cooled liquid
  • Nucleation in sub-cooled and saturated liquid
  • Slugging
  • Annular Flo
  • Droplet entrainment
  • Complete dry out to superheated vapour

Demonstration of two phase flow with increasing vapour content

Demonstration of effect of air in condensers


A. 650W 220/240 Volts, Single Phase, 50HZ. (With earth/ground)


B. 650W 110/120 Volts, Single Phase, 60Hz (With earth/ground)

Cooling Water:

2 litre per minute at 10m head continuous (for condenser).

10 litre per minute at 20m head occasionally (for vacuum pump).