Design analysis and experimental verification of insulation blankets for civil aircraft nacelle and pylon

Abstract The nacelle and pylon structures of civil aircraft, due to their proximity to the engine, are significantly affected by the high-temperature components of the engine. To reduce the impact of high temperatures on the nacelle and pylon structures and their internal systems, insulation blankets are typically arranged on the inner side of the nacelle fan cowl, the inner side of the core cowl, and the bottom area of the pylon to decrease the thermal transfer effect from the high-temperature components of the engine and the hot air inside the core compartment to the nacelle and pylon structure. This paper mainly describes the structural design method and requirements for the nacelle pylon insulation blanket, and through thermal analysis theoretical calculations, the temperature changes on the cold side of the insulation blanket at different hot sides are derived. The results are compared with the insulation test results of the insulation blanket test pieces, further verifying the insulating performance of the blanket. In addition, environmental qualification tests were conducted on the insulation blanket test pieces, and insulation tests were re-performed on the test pieces after environmental testing, demonstrating the reliability of the nacelle and pylon insulation blanket design.