Experimental and numerical simulation studies on heat flux measurement for slug calorimeters in the conduit

The slug calorimeters in the supersonic turbulent conduit of the arc heated wind tunnel were improved.The line-contact calorimeter and the calorimeter which has a 0.4mm gap betwenn the heated end brim of the slug and the test article are adopted.Comparing to measured heat flux data by the typical slug calorimeters,the experimental results show that the output characteristics of the three types of calorimeters have good consistency under the condition of low pressure and low cold-wall heat flux;as pressure increases,the measurement values of the line-contact calorimenters slightly decrease and the measurement values of the 0.4mm gap calorime-ters increase noticeably.To explain the result,the flow characteristics of the 0.4mm gap clorim-enters are investigated.The influence of the free stream Mach number on the flow in the gap is also studied.