"Dynamic mode of heat exchangers is typical for a number of technological thermal plants , as well as air-heating systems , ventilation, and air conditioning. Technologically predetermined control algorithm operating mode heat exchangers in practice implemented by means of manual or automatic adjustment in one or more control parameters . Obviously, the most efficient in the energy and technically and economically dynamic mode control algorithm of the heat exchanger can be detected only in the form of a review of the relevant mathematical model. In this paper we consider a mathematical model of the dynamic operation of the system of heat exchangers with natural air circulation . As input parameters are considered the temperature of hot and cold air streams. Modeled by changing the inputs are heat exchangers and the extent to which these changes will not affect the operation of the entire system. In order to keep the temperature at the i- MOT has not changed , the coefficient of variation should tend to zero , since all the other quantities are limited by technical parameters of the system . By changing the values ​​of the input parameters is analyzed mass flow of hot flow limits are changing the output parameters of the preceding heat exchangers that will not change the entire system ."

Keywords: heat loss into the environment, the starting temperature of the hot (cold) flow, the final temperature of the hot (cold) flow, the range of variation of hot, cold flow