In a surface condenser, how does the cooling water circulate?

In a surface condenser, the cooling water circulates by passing through the tubes. This design is crucial because it allows for efficient heat exchange between the steam and the cooling water. As steam enters the condenser and comes into contact with the cooler surfaces of the tubes, it loses heat and condenses back into water. The cooling water, which is typically from a nearby water source or cooling tower, flows inside the tubes, absorbing the heat from the steam.

This method is advantageous as it keeps the cooling water separate from the steam, preventing contamination and ensuring that the steam condenser remains clean and efficient for operation. The cooling water is then typically sent back to be cooled again, either in a cooling tower or through some other means, to repeat the cycle.

Other methods of circulation, such as spraying the water into the condenser or mixing it with steam, are less efficient and could lead to issues such as contamination or inadequate cooling, thus affirming why the choice of having the water pass through the tubes is the correct answer.