Comparative analysis of some methods for calculating the characteristics of the heat exchange process in turbomachines during jet cooling

At the initial stages of design, performing a complete 3D analysis of the processes occurring in the elements of cooling systems of modern high-temperature engines can be either very costly in terms of computational processes, or even impossible due to the lack of necessary geometric 3D models at these design stages. But already at the initial stages of design, it is very important to determine the rational characteristics of the cooling systems of the elements of such engines as reliably as possible, since it is often on the basis of such assessments that the most important technical and economic decisions are made that determine the final characteristics of the designed facility. Correcting the consequences of incorrectly made decisions at this stage of design, if they are made, can be difficult and costly, and in some cases impossible. The relevance of using the criterion equations obtained by various authors to evaluate the necessary parameters is substantiated. The long-term practice of using such equations to perform an engineering analysis of cooling systems has confirmed both the high reliability of the results obtained and the relatively low labor costs of engineers to perform the work, which significantly reduces the iteration time required to make correct technical decisions and achieve optimal configuration of various cooled elements (housings, chamber parts combustion chambers, cooled blades, etc.) as soon as possible. A comparative analysis of the characteristics of the element of the cooling system of a turbomachine is performed using the criterion equations obtained by various authors. There is a fairly good agreement between the results of calculating the heat transfer coefficient when calculating using various criterion equations, and the possibility of using these criterion equations in practical calculations is considered. The necessity of developing a software module using optimization approaches to find rational parameters of cooling systems using jet methods of organizing the movement of cooling air is emphasized.