Abstract <p>This paper is dedicated to developing a new approach to modeling pressure redistribution during compressed air flow between connected volumes. The proposed modeling methodology is based on an energy approach, similarity theory, and motion theory. This method for calculating pressure changes is designed for modeling both general-purpose industrial pneumatic systems and calculating the pneumatic brake systems of automobile and rail vehicles. The advantage of this new approach is that the main calculation parameters are the reservoir volume and the diameter of the inlet and bypass ports, i.e. these parameters can be pre-calculated without the need for specialized instruments. Furthermore, a coefficient is introduced into the model for adjusting the air wave velocity, which allows for simple functions to improve modeling accuracy and describe the characteristics of air flow through non-standard channels. Experimental studies have shown that the model has a sufficiently high convergence, and the relative error does not exceed 1.5%. Consequently, this method of modeling pneumatic processes can be used to simulate the operation of components and assemblies of general-purpose pneumatic systems, as well as brake equipment for motor car and railway rolling stock. It will also simplify the process of developing “digital twins” for these systems.</p>