Experimental investigation of turbulent flow characteristics in a cross-flow fan*

Cross-flow fans are utilized in applications such as air-conditioner indoor units due to their advantage of generating uniform airflow across the entire length with a compact design. Compared to axial or centrifugal fans, cross-flow fans have a significantly longer spanwise length and a structural characteristic where the impeller consists of multiple blocks, leading to turbulent flow variations in the spanwise direction. However, cross-flow fans are a relatively recent innovation compared to conventional fans, resulting in a relative scarcity of research and data on their flow characteristics. In this study, we aim to investigate how turbulent flow characteristics change in the spanwise direction by experimentally measuring the flow around a cross-flow fan used in an actual air-conditioner indoor unit. The flow field of the cross-flow fan was measured in the region from the center to the edge of the impeller using Particle Image Velocimetry (PIV). The flow rate discharged from the joint disk (the boundary between impeller blocks) was lower than that from the center of the blocks. Additionally, the joint disk increased flow instability around the stabilizer compared to the block center. More details will be discussed in the presentation.