用于高温高压剪切流场的Gardon计研制

传统Gardon计一般为薄壁康铜片结构,通常应用于辐射热流的测量。当应用在高压对流环境中,存在承压能力不足、受对流加热不均匀性影响的问题。从Gardon计基本原理出发,以数值仿真分析了康铜箔厚度对传热特性的影响,推导了对流环境测量误差与对流换热系数和灵敏度系数的明确显式关系;并利用数值计算验证了其正确性。根据理论分析,设计并研制了适用于电弧风洞流场的Gardon计和复合型热流传感器,后者集成了Gardon计和水卡计的功能,可同时用两种方法测量表面热流。标定实验结果显示,传感器样件均具有较好的线性度(小于1.5%)和时间常数,水卡计经固定系数修正后与标准热流相对误差小于3.7%,当戈登计受对流换热影响较大时,可为其提供参考。

Design and Fabrication of Gardon gage used in shear flow filed of high temperature/pressure

Gardon gages are a kind of thin-wall constantan structure, which are frequently used to measure radiation heat flu. When applied in high pressure and heat convection environments, drawbacks raise in bearing capacity and non-uniform convection heating. This study has simulated heat transfer characters of different thickness of constantan foil by the heat flux heating mechanism of Gardon gage. And an explicit expression has been deduced between measuring error, convective heat-transfer coefficient and sensitivity coefficient, which is confirmed by numerical calculation. With the aid of numerical results, a new Gardon gage and hybrid heat flus sensor are designed and fabricated, which are applicable in arc wind tunnel. In addition, the hybrid sensor integrates functions of Gardon gage and calorimeter to measure heat flux in two ways. The calibration experiment results have shown that the new heat flux sensors are good in linearity and time constant. The relative error is under 3.7% between the corrected measuring result of calorimeter and standard heat flux measuring result. When Gardon gage are clearly affected by convection heating, the calorimeter can be referred to.