复杂背景下三维弯曲表面红外测温修正

Infrared temperature measurement correction of three-dimensional curved surface under complex background

航空发动机涡轮叶片的断裂脱落与叶片温度密切相关,准确测量涡轮叶片温度对航空发动机的安全运行具有重要意义。针对涡轮叶片材料发射率不均匀、周围高温物体反射严重以及探测角度变化等因素导致传统红外辐射测温方法精度难以保证的问题,基于辐射传输理论与红外热成像测温原理,分析了对红外测温结果影响的主要因素,提出了复杂背景下三维弯曲表面红外辐射测温的修正模型。通过设计实验测量获得弯曲表面的发射率、双向反射分布函数、角系数等重要参数,根据提出的温度修正模型,得到弯曲表面红外修正温度。通过与典型位置上热电偶的测温结果对比,测温误差由修正前的4%左右下降到1%以内,证明了所提的修正模型具有较高的精度和适应性,可为涡轮叶片气动传热试验技术的提升和航空发动机等重大装备的研制提供支撑。

The fracture and shedding of turbine blades in aero-engine systems are intimately linked to blade temperature.The precise measurement of turbine blade temperature is significant for ensuring the safe operation of aero-engines.However,traditional infrared radiation temperature measurement methods often face challenges in maintaining accuracy due to factors such as the non-uniform emissivity of turbine blade materials,pronounced reflections from high-temperature objects in the surroundings,and variations in detection angles.To address these issues,this article leverages the principles of radiation transfer theory and infrared thermal imaging temperature measurement to analyze the key factors that influence temperature measurement results.A modified model for infrared radiation temperature measurement of three-dimensional curved surfaces under complex backgrounds is formulated.To obtain the necessary parameters for the temperature correction model,the experimental measurement is designed to determine crucial factors such as emissivity,bidirectional reflection distribution function,and angle coefficient for the curved surface.By applying the temperature correction model proposed in this study,the infrared-corrected temperature values for the curved surface are derived.Comparative analysis of these results with temperature measurements obtained from thermocouples positioned at representative locations demonstrates a reduction in temperature measurement error from approximately 4%prior to correction to less than 1%.This result substantiates the high accuracy and adaptability of the proposed correction model,underscoring its potential to provide valuable support for enhancing aerodynamic heat transfer test technology and facilitating the development of major aero-engine equipment,particularly turbine blades.