Inlet chambers (IC) are the typical upstream component of centrifugal compressors, and inlet guide vanes in the IC have a great impact on its internal flow and aerodynamic loss, which will significantly influence the performance of the downstream compressor stages. In this paper, an experimental study was carried out on the flow characteristics inside a radial IC of an industrial centrifugal compressor, including five testing sections and 968 measuring points for two schemes with and without guide vanes. Detailed distributions of flow parameters on each section were obtained as well as the overall performance of the radial IC, and the causes of the flow loss inside the IC and the non-uniformity of flow parameters at the outlet section were investigated. Besides, numerical simulations were performed to further analyze the flow characteristics inside the radial IC. The experimental and numerical results indicate that, in the scheme without guide vanes, sudden expansions in the spiral channel and flow separations in the annular convergence channel are the major sources of flow loss and distortions generated in the radial IC; while in the scheme with guide vanes, the flow impacts, separations and wakes caused by the inappropriate design of guide vanes are the main reasons for the flow loss of the IC itself and the uneven flow distributions at the IC outlet.

进气室（IC）是离心压缩机的典型上游组件，而IC中的进气导叶对其内部流量和空气动力学损失有很大影响，这将显着影响下游压缩机级的性能。本文对工业离心压缩机径向IC内部的流动特性进行了实验研究，包括五个测试部分和968个测量点，用于两种方案（带和不带导叶）。获得了每个截面上流量参数的详细分布以及径向IC的整体性能，并研究了IC内部流量损失的原因以及出口截面上流量参数的不均匀性。除了，进行了数值模拟，以进一步分析径向IC内部的流动特性。实验和数值结果表明，在没有导流叶片的方案中，螺旋形通道的突然膨胀和环形会聚通道的流动分离是径向IC产生流量损失和变形的主要来源。而在采用导流叶片的方案中，由于导流叶片设计不当而引起的流动冲击，分离和尾流是IC自身流量损失以及IC出口处流量分布不均匀的主要原因。螺旋通道的突然膨胀和环形会聚通道的流动分离是径向IC中产生的流量损失和变形的主要来源；而在采用导流叶片的方案中，由于导流叶片设计不当而引起的流动冲击，分离和尾流是IC自身流量损失以及IC出口处流量分布不均匀的主要原因。螺旋通道的突然膨胀和环形会聚通道的流动分离是径向IC中产生的流量损失和变形的主要来源；而在采用导流叶片的方案中，由于导流叶片设计不当而引起的流动冲击，分离和尾流是IC自身流量损失以及IC出口处流量分布不均匀的主要原因。