Simulation of contact thermal resistance when designing processing equipment

Analysis of the processing equipment structures when designing according to the temperature criterion is a necessary guarantee of ensuring the required performance characteristics. The presence of a significant number of parts in the processing equipment units and mechanisms requires, when designing, the prediction of the heat flow passage through the joints. When simulating contact thermal resistance, the variety of requirements for a joint can be taken into account by introducing a pseudolayer into the contact zone. The paper presents test results of the proposed regression dependence of the temperature change when the heat flow goes through the pseudolayer obtained considering four significant factors: the pseudolayer thickness, the nominal pressure, the material yield strength, and the actual contact zone location. The adequacy of the specified regression dependence was verified experimentally and applying numerical simulation using large-block finite elements. To describe the process of heat transfer in the thermal model elements, the authors determined contact thermal resistances for several conditions for the heat flow propagation: from one finite element to another within one part; from one finite element to another located in an adjacent part; heat flow passing through closed cavities; heat flow propagation into the environment for finite elements located on the outer (free) contour of the part. The experiments showed a good agreement between the experimental data and the simulation results. The application of large-block finite elements based on the proposed contact thermal resistance model allowed bringing the FE simulation technique to engineering use without complex software.