How is a vacuum created in a Main Condenser when it comes to power plant operation.
Without the use of air ejectors or Vacuum pumps.
Remember what happens in a condenser. Energy is lost from the fluid stream. The fluid changes from a gas to a liquid (condenses). Since liquids take up less volume as the same mass of a gas at when the phase changes a vacuum must be created which will draw in more gas to be cooled.
Niel
Steam when condensed into water reduces in volume drastically at the order of thosands depending upon the pressure existing inside the condenser, e.g. around 14500 times at 0.1 bar. This enormous reduction in volume creates the vacuum inside the condenser.
In other words, the specific volume of water at a given pressure is many times lower than that of steam. (can be read from a steam table)
The ejector or vacuum pumps aid in removing the non condensible gases thereby enhancing the condensation / heat transfer to the cooling water.
