This paper describes heat exchangers as well as their division, and describes in more detail the tube-in-plate heat exchanger that was used to solve the problem. The focus of the work is on the study of heat transfer between two fluids flowing through a heat exchanger. The main goal of the work is to optimize the design of the tubular heat exchanger in order to achieve better performance at lower costs. The influence of geometrical dimensions on pressure drops was examined. The geometrical parameters that have been examined are the number of baffles, the number of tubes and the diameter of the heat exchanger shell. Analysis of the results shows that certain geometric parameters, such as the length and diameter of the pipe, significantly affect the heat transfer and pressure drop in the system. To obtain the optimal solution, a square and triangular pitch-tube layout and various external pipe diameters, pipe pitches, shell diameters, pipe numbers and pipe passage numbers were applied. Finally, the optimal results for the square and triangular pipe arrangement were selected. Modeling and optimization was performed using the program code written in the software program EES (Engineering equation solver). The solutions are presented in the form of a table.