What is the main purpose of a heat exchanger on a vessel?

The main purpose of a heat exchanger on a vessel is to transfer heat between two or more fluids without mixing them. This essential function allows for efficient thermal management in various systems onboard, including those used for cooling engines or heating water in the ship's systems. In marine applications, heat exchangers are vital for transferring heat from engine coolant to a separate seawater system, thus maintaining optimal operating temperatures while preventing contamination of the fluids involved.

In contrast, generating steam for propulsion often requires boilers, which use heat from combustion processes rather than transferring between fluids. The function of filtering impurities relates more to the systems that manage water quality, which do not primarily involve heat exchange principles. Lastly, while fuel combustion efficiency can be influenced by temperature management, it is not the direct purpose of a heat exchanger, which focuses more specifically on the transfer of thermal energy between fluids.