传统的天平测力系统只能测量整体载荷而无法解耦单个部件贡献，这限制了对气动载荷背后的流动机理的探索。随着粒子图像测速技术（PIV）的发展，提出了一种基于PIV的气动载荷测量技术，通过重构压力、密度等多物理场，实现气动载荷的间接测量。但是传统的压力场重构方法应用于超声速流场时性能严重降低，限制了重构测量方法在超声速喷管中的应用。为解决上述问题，提出了一种基于流通矢量分裂（FVS）技术的超声速压力场重构方法，并建立了一套基于PIV的超声速喷管的推力性能测量方案。通过开展直连式喷管风洞PIV实验，重构了典型工况下喷管内流场的多物理场以及流量、推力、升力等气动性能参数。评估结果表明，基于FVS方法计算的重构数据拥有更高的精度以及良好的自洽性，满足流量、动量守恒规律，即使是复杂的过膨胀工况下推力和升力的相对误差仅为?1.70%和0.60%，激波后壁面压力的局部误差均低于3%，优于传统的Poisson法和空间积分法。因此，实验结果验证了基于PIV的超声速喷管推力性能重构测量方法的可行性以及高精度，可以为传统天平测力结果提供有效的数据补充。
The conventional force measurement system using balance has the problem of only being able to measure the overall loads but unable to decouple the contribution of individual components, which limits the exploration of the flow mecha-nism behind aerodynamic loads. With the development of Particle Image Velocimetry (PIV) technology, a PIV-based aer-odynamic load measurement technology has been proposed, which indirectly measures aerodynamic loads by recon-structing multiple physical fields such as pressure and density. However, the performances of conventional pressure re-construction methods were severely deteriorated when applied to supersonic flow fields. This drawback limited the appli-cation of reconstruction measurement methods in supersonic nozzles. To resolve this issue, a supersonic pressure recon-struction method based on the Flux Vector Splitting (FVS) technique was proposed, and a thrust performance measure-ment scheme for supersonic nozzles based on PIV was established. PIV experiments of the single expansion ramp noz-zle were conducted using the direct-connect wind tunnel. Multiple physical fields and aerodynamic performance parame-ters such as flow rate, thrust, and lift were reconstructed under typical operating conditions. The evaluation results showed that the data reconstructed by the FVS method possessed higher accuracy and better self-consistency, satisfying the laws of mass and momentum conservation. The relative errors of thrust and lift under overexpansion conditions were only -1.70% and 0.60%, respectively. The local errors of wall pressure after shock wave were lower than 3%. The per-formance was better than the conventional Poisson method and spatial integration method. Therefore, the experimental results verified the feasibility and high accuracy of the PIV-based thrust performance reconstruction measurement meth-od when applied in supersonic nozzles, which can provide effective data supplementation for balance measurement.
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