What is the function of a heat exchanger?

The function of a heat exchanger is to transfer heat between two fluids without allowing them to mix. This is achieved through the use of heat exchanger components, which maintain a barrier between the two fluids while enabling efficient heat transfer. The design ensures that one fluid can lose heat while the other gains it, making heat exchangers essential in various applications, such as heating, cooling, refrigeration, and power generation.

In many systems, the ability to separate fluids while exchanging thermal energy is crucial for maintaining the integrity and performance of the system. By preventing the fluids from mixing, heat exchangers can effectively regulate temperatures without altering the properties of the fluids involved.

The other options, while related to thermal processes, do not accurately describe the primary function of a heat exchanger. Storing thermal energy pertains to thermal storage systems. Increasing the pressure of fluids refers to pumps or compressors. Changing the state of matter involves processes like boiling or condensation, which are not typically the direct function of a heat exchanger.