Study on the influence of key structural parameters of turbine heat shields on the thermal load of bearing shell

Increasing engine power outputs have raised exhaust gas temperatures, intensifying thermal stresses on turbine systems and compromising bearing reliability through accelerated seal ring degradation and oil coking. Heat shields installed between turbines and bearings mitigate heat transfer, with their insulation efficiency critically dependent on structural parameters and assembly configurations. This study employs experimental testing and multi-physics simulations to analyze how heat shield inner rim designs (open vs. closed states) and diameter affect thermal insulation. Numerical models demonstrated strong alignment with experimental data across bearing housing measurement points, validating their accuracy. Results showed that closed inner rim configurations reduced temperatures at critical bearing locations—specifically the turbine-end sealing ring, oil inlet wall, and turbine-end floating bearing—by 11.2–16.0 K, 6.3–7.1 K, and 3.8–6.9 K, respectively, compared to open configurations. Additionally, reducing the inner rim diameter provided further temperature reductions of approximately 2 K at these locations. The combined effects of minimized inner rim diameters and closed-edge designs yielded optimal thermal insulation, effectively attenuating heat flux propagation to bearing systems. These findings underscore the importance of geometric optimization in thermal shield design, offering actionable strategies to enhance component durability under extreme thermal loads. • Studied how heat shield inner rim's structural features impact insulation. • Inner rim's closed/open state is a key factor determining insulation efficiency. • Minimizing inner rim size enhances heat shield insulation performance. • Flow/heat transfer mechanisms improving insulation was been analyzed.