The numerical investigation of outlet guide vane heat transfer

Abstract

Aero-engine components are subjected to high thermal loads and uneven temperature distribution during working conditions. The heat transfer investigation plays a significant role in the development and analysis of these structures. To increase the understanding of the heat transfer over a Turbine Rear Structure(TRS), tests are conducted at experimental facilities giving good insights and valuable inputs for possible design improvements. The primary objective of this thesis is to utilize the available heat transfer experimental data from the Chalmers LPT-OGV(Low Pressure Turbine-Outer Guide Vane) test rig to validate the CFD methodology for aero-thermal heat transfer analysis. In this work, the CFD heat transfer predictions are compared to the heat transfer test data obtained from the LPT-OGV test rig which is capable of replicating realistic engine conditions. The same operating conditions as in the test facility are used on the CFD model to reproduce numerical results. A comparative analysis of heat transfer coefficients (HTC) is conducted between the CFD predictions and the experimental data obtained from the LPT-OGV test rig, considering both on-design and off-design cases. The wake shedding effects on heat transfer for off-design conditions is investigated using a transient solver. Furthermore, a detailed analysis is conducted to examine the formation of film coefficient profiles over the hub region, which are then compared against the corresponding experimental data The findings revealed that, in general, transition of flow is observed over the suction side of OGV. CFD simulations tend to under predict the experimental HTC values. The SST transition model captures the transition effect, but predicts an earlier transition when compared with experimental data. The film coefficient profiles formed through CFD exhibited similarity to experimental profiles, although the experimental values displayed greater dispersion. These results contribute to the understanding and validation of CFD methodologies using experimental data, while also highlighting areas where further improvements are necessary