As motive force of processes, heat must be transferred from one fluid to other, task that is performed by means of heat exchangers. From this point of view, heat exchangers represent an important element of thermal facilities that has substantially contributed to technical development of the society. Today it is impossible to imagine any branch of process engineering and energy technology without involvement of heat exchangers. Advanced models of these apparatus were proposed in the middle of the 18th century, while theoretical backgrounds have been completed a century later
