The pressure distribution around wedge models inside a submillimeter supersonic wind tunnel was experimentally investigated using pressure-sensitive paint (PSP) at a flow speed of Mach 1.6. The throat of the submillimeter supersonic wind tunnel was 500 μm. The two wedge models were isosceles triangles with a width of 50 μm and vertex angles of 20° and 30°, respectively. The pressure profiles and pressure distributions along the centerline inside the submillimeter supersonic wind tunnel with the wedge models agreed with the results of numerical simulation performed using ANSYS Fluent. The pressure distributions around the wedge models were examined, and a strong pressure rise at the front end of the wedge models was observed. A low-pressure region in the wake region downstream of the wedge models was identified. However, these results differed from the simulation data for the middle layer of the wind tunnel, which revealed bow shock and a shock wave interaction. This difference occurred because the PSP coating was located at the bottom of the wind tunnel, which was embedded inside a viscous layer. The pressure data measured with PSP were smeared, and it was consistent with the simulation data for the bottom layer. The PSP results reveal the overall pressure variation around the wedge models, and they will be useful for future designs of micro propulsion systems with supersonic nozzles.

亚毫米超音速风洞内楔形模型周围的压力分布使用压敏涂料 (PSP) 以 1.6 马赫的流速进行了实验研究。亚毫米超音速风洞的喉道为 500 μm。两个楔形模型是等腰三角形，宽度为 50 μm，顶角分别为 20° 和 30°。采用楔形模型的亚毫米超音速风洞内沿中心线的压力剖面和压力分布与使用 ANSYS Fluent 执行的数值模拟结果一致。检查了楔形模型周围的压力分布，并观察到楔形模型前端的强烈压力上升。确定了楔形模型下游尾流区域中的低压区域。然而，这些结果与风洞中间层的模拟数据不同，这揭示了弓形冲击和冲击波的相互作用。之所以会出现这种差异，是因为 PSP 涂层位于风洞底部，它嵌入粘性层内。用PSP测量的压力数据被涂抹，与底层的模拟数据一致。PSP 结果揭示了楔形模型周围的整体压力变化，它们将有助于未来的微型设计带有超音速喷嘴的推进系统。