What characterizes a surface condenser?

A surface condenser is characterized by circulating water flowing through the tubes. In this type of condenser, steam from the steam engine or turbine passes over the outside of the tubes, while a separate supply of cooling water circulates inside the tubes. This design allows the steam to condense into water without coming into direct contact with the cooling water, which is crucial for maintaining water purity and avoiding contamination.

The effectiveness of a surface condenser is largely dependent on its ability to efficiently transfer heat from the steam to the circulating water, allowing the steam to condense and convert back to liquid water, which can then be reused in the boiler system. This process is vital for maintaining the thermodynamic cycle, enabling optimal operation of the steam system.

The other characteristics mentioned do not accurately define a surface condenser: it does not have exhaust steam flowing through the tubes as that would compromise the separation of steam and cooling water; it typically operates under lower pressure compared to other types of condensers, as it is designed for efficient heat exchange at vacuum conditions; and it is not used exclusively for heating purposes, but primarily for condensing vapor back into liquid in energy processes.