Stereoscopic PIV Measurement on Multi-Blade Fan

There are many sources of noise in multi-blade fan near the trailing edge of blades or cut-off region of the casing. The flows passing through the impeller of a multi-blade fan that is now being used as a blower for automobile air conditioner system have been successfully quantified by a stereoscopic PIV technique. Eight test sections are chosen at the inlet flow of the impeller changing the measurement angles, 0, 45, 90, 135, 180, 225, 270 and 315 degrees from cut-off point of its casing. The calibration for cameras is conducted at 9 planes within the blade width of the impeller. It is revealed that the velocity distributions are strongly influenced by the casing and cone shape, and there exists a symmetrical spiral flows in the inner part of the impeller because cut-off part of its casing disturb the fluid flow.