采用计算流体动力学（CFD）方法对气体轴承-转子系统进行流场特性仿真时，气膜厚度是至关重要的结构参数之一，但零件加工过程中产生的形状、尺寸误差以及系统装配造成的偏差等，会导致实际气膜与理想设计气膜在空间形貌及尺度上存在一定的偏差，进而影响数值计算结果的可靠性及准确性。为此，该文首先提出了流场有效气膜厚度的概念，通过双向流固耦合数值仿真与实验结果的对比分析及修正，最终确定合理的等效气膜厚度。研究结果表明：采用双向流固耦合数值仿真方法可揭示气膜流场瞬态特性及转子姿态的变化规律，并对气体轴承-转子系统是否能够安全运行进行预判和评估，节省了实验测试成本；采用转子倾斜角作为对比分析特征，为数值仿真结果和实验测试结果之间的系统性能偏差分析提供了直观的参考依据；等效气膜厚度的建立可最大程度上简化数值仿真模型，提高数值仿真效率，同时其结果又具有一定的可靠性；以供气压力0.6 MPa、单边稳态力80 N为例，通过误差分析和逼近，循环建立和修正流固耦合仿真模型中预估的等效气膜厚度，最终将系统倾斜角的相对误差控制在5%以内，极大地提高了数值仿真结果与实际工程系统性能的一致性，进而为气体轴承-转子仿真系统在结构设计、性能预测及评估中的应用提供了可靠方法及依据。

When simulating the flow field characteristics of the gas bearing-rotor system using the computational fluid dynamics (CFD) method, the gas film thickness is one of the crucial structural parameters. However, shape and dimensional errors arising during component machining, as well as the deviations caused by the system assembly, can lead to certain discrepancies between the actual gas film and the ideal designed gas film in terms of the spatial morphology and scale. This further affects the reliability and accuracy of the numerical calculation results. Therefore, this paper first proposed the concept of effective gas film thickness for the flow field. Through the comparative analysis and correction of the bidirectional fluid-structure interaction numerical simulation and experimental results, the reasonable equivalent gas film thickness was finally determined. The research results show that the adoption of the bidirectional fluid-structure interaction numerical simulation method can reveal the transient characteristics of the gas film flow field and the variation law of the rotor attitude, and predict and evaluate whether the gas bearing-rotor system can operate safely, saving the cost of experimental testing. The rotor inclination angle was adopted as the comparative analysis feature, providing an intuitive reference basis for the system performance deviation analysis between numerical simulations and experimental tests. The established equivalent gas film thickness maximally simplifies the numerical simulation model while enhancing computational efficiency, and simultaneously maintains reasonable result reliability. Taking a supply pressure of 0.6 MPa and a unilateral steady-state force of 80 N as an example, through error analysis and approximation, the estimated equivalent gas film thickness in the fluid-structure interaction simulation model was cyclically established and corrected. Eventually, the relative error of the system inclination angle was controlled within 5%, which greatly improved the consistency between the numerical simulation results and the performance of the actual engineering system. Furthermore, this approach provides a reliable method and basis for the application of the gas bearing-rotor simulation system in structural design, performance prediction and evaluation.