Film wise And Dropwise Condensation And Boiling
- Heating and condensing takes place inside a partially filled glass vessel.
- A heater coil heats the water.
- The temperature of the wire reaches significantly higher than 100°C.
- Students watch the boiling process and note the different boiling processes.
- For boiling heat transfer experiments, students adjust the current in a resistant wire heater element in the water.
These include:
Subcooled boiling: where small bubbles form and rise. Nucleate boiling: where large bubbles form and rise. Film boiling: unstable and stable, where a vapour blanket forms and heat transfer by radiation becomes important. For condensing heat transfer experiments, water condenses on two water-cooled vertical cylinder specimens. The cooling water flow rate and its temperature change at each cylinder helps students to find the heat transfer.