为研究伞衣微孔透气结构的射流特性，该文基于TexGen建立了2种织物的微观模型，采用计算流体动力学（computational fluid dynamics，CFD）技术开展了不同压差下的孔隙射流流场研究，探究了沿孔隙中心轴线速度和压力的变化规律。结果表明：不同孔隙结构织物均有相似的流场分布规律，孔隙射流存在速度增幅区、速度衰减区、尾流衰减区和尾流过渡区4个区域；沿轴向的速度、压力梯度主要出现在速度增幅区和速度衰减区；中心轴线的最大速度点和最小压强点均位于孔隙喉部后方约0.145t（t为织物厚度）处；尾流衰减区的流动特性不受内外压差的影响，当压差大于200 Pa时，织物孔隙内和尾流场的流动特征参数变化仅由织物结构决定。结合射流区长度与织物透气量间的指数衰减关系提出了普适的射流影响域模型。该文研究方法对探究透气降落伞的精细尾流结构，提高透流伞衣流场模型的准确性具有重要意义。

[Objective] Parachutes are widely used in aviation, aerospace, and weapon fields as an efficient and economical aerodynamic deceleration device. The drag force of a parachute mainly comes from the pressure differential on both sides of the permeable canopy. The essence of canopy permeability is that the air flows through the fabric pores to form a jet, thus affecting the flow field around the parachute and, subsequently, the aerodynamic performance of the parachute. To study the aerodynamic performance of a parachute, the micropore jet and permeability characteristics of its canopy fabric must be thoroughly investigated.[Methods] The micromodels of fabrics with high and low porosities were established on the basis of TexGen, numerical calculation of the pore jet flow under different pressure differentials was performed using computational fluid dynamics, and the numerical permeability values were compared with the experimental values. Then, the pressure and velocity of the jet domain were analyzed. The jet domain was divided into four regions according to various velocity and pressure characteristics along the central axis of the pores. Since the quantitative analysis of the jet domain under different pressure differentials was difficult, the relative pressure differential and relative velocity without the dimension parameters were proposed. On this basis, the jet characteristic parameters were proposed along with the application of the jet theory. The parameter change rule of different fabrics under different pressure differentials was analyzed. Moreover, the factors influencing the jet parameters were studied. Finally, the Levenberg-Marquardt optimization algorithm was used to fit the influence range of the jet domain based on the single-phase exponential decay function, and the experimental results were compared with the numerical results.[Results] The numerical results of the micropore jet flow field showed that:(1) The velocity of air increased within the pore and decreased after the outflow, while the pressure changed occur inversely. The pressure gradient was concentrated in the pore. (2) The jet flow field comprised four zones:velocity increase zone, velocity decay zone, wake decay zone, and wake transition zone. The changes in the velocity and pressure gradients along the direction of air flow primarily occurred in the velocity increase and velocity decay zones. The maximum velocity value of the central axis and the minimum pressure value were located in the adjacent pore throat. The flow characteristic parameters in the wake decay zone were not affected by the influence of the pressure differential. (3) When the pressure differential exceeded 200 Pa, the flow characteristic parameters in the fabric pore and the jet domain were determined only by the fabric structure. (4) The influence range of the jet domain increased with the porosity and shares an exponential decay relationship with the air permeability.[Conclusions] In this paper, the variation law of velocity and pressure in the fabric microporous jet flow domain is studied based on the numerical results of the pore jet flow field under different pressure differentials. The jet domain calculation model suitable for the parachute fabric is established. The research method proposed in this paper is highly significant in exploring the fine-flow field structure of the permeable parachute and improving the accuracy of the flow field model of the permeable canopy.