Heat exchangers are components for transferring thermal energy between two material flows, whereby the media do not flow through each other. Depending on the application, both media can be gaseous (exhaust gas heat utilisation, charge air coolers for combustion engines) or liquid (storage boilers, district heating networks). A combination of gaseous and liquid media is also possible, for example in gas boilers and in direct charge air cooling. Furthermore, phase transitions can occur depending on the application. Functionally, heat transfer takes place via parallel, heat-permeable heat plates, spirals, U-tubes, jacket tubes or tube bundles through which both substances are conducted. The direction is decisive for the efficiency: counterflow, co-current and crossflow are possible design variants; cross-counterflows are also possible. Heat exchangers, also known synonymously as heat exchangers or heat exchangers, can be used in many ways in industry and automotive engineering. Cooling water coolers, oil coolers and charge air coolers are typical vehicle components.