Analysis of test and simulation results of a Compact Heat Exchanger for Aerospace applications

This thesis presents the results of a comprehensive study conducted at Thales Alenia, focusing on a counter-current compact Heat Exchanger (CHX) manufactured using additive manufacturing techniques. The heat exchanger features an internal structure known as Triply Periodic Minimal Surface (TPMS), specifically a gyroid design. The study employed computational fluid dynamics (CFD) simulations, as well as practical laboratory tests to compare the results . The primary objective of the present report was to evaluate the accuracy of computational models by comparing computational outputs with the experimental results. The research was structured into three main phases: simulation, experimentation, and comparison. Initially, CFD techniques were utilized to simulate the fluid dynamics within the heat exchanger. The simulations aimed at replicating the real conditions faced by the CHX in the facility of the company. These simulations were performed by STAR-Ccm+, an industry-standard software. A dedicated experimental campaign was conducted using the laboratory equipment available at Thales Alenia. These tests aimed at developing a direct comparison between the simulated and experimental data. Various parameters such as pressure, velocity, and temperature were measured and recorded during these tests. While the evaluation of the rpessure4 drop turned out to suffer by large uncertainties, the thermal measurements were considered reliable enough to be used for the numerical model validation. The final phase consisted then in the comparison of the data obtained from both the CFD simulations and the laboratory experiments. Error quantification techniques were employed to assess the level of agreement between the two sets of results. The results confirmed the robustness of the numerical model and also demonstrated that the CFD model can be successfully used in the future for the design of the HX.