Performance measurements, flow visualization, and numerical simulation of a crossflow fan

Abstract

A 12-inch diameter, 1.5-inch span crossflow fan test apparatus was constructed and tested using the existing Turbine Test Rig (TTR) as a power source. Instrumentation was installed and a data acquisition program was developed to measure the performance of the crossflow fan. Performance measurements were taken over a speed range of 1,000 to 7,000 RPM. Results comparable to those measured by Vought Systems Division of LTV Aerospace in 1975 were obtained. At 6,000 RPM, a thrust-to-power ratio of one was determined; however, at 3,000 RPM twice the thrust-to-power ratio was measured. Flow visualization was conducted using dye-injection methods. Performance and flow visualization results were compared to predictions obtained from 2-D numerical simulation conducted using Flo++, a commercial PC-based computational fluid dynamics software package by Softflo. A possible design for a light civil V/STOL aircraft was suggested using a similar crossflow fan apparatus for both lift and propulsion.