The newly developed split-film anemometer probe, manufactured by Thermo- Systems, Inc. of St. Paul, Minnesota, has been applied to the measurement of two-dimensional turbulence characteristics, including turbulent shear stress, in mixing layer and boundary layer shear flows. Probes of both 6-mil and 2- mil diameters were used which had the same physical dimensions as ordinary hot-film anemometer probes. The film on this sensor is split into two 170° elements resulting in two independent sensors. This enables the probe to detect vertical as well as axial components of the instantaneous velocity vector. It therefore serves the same purpose as an x-probe, but because of its very small size it has significant advantages in regions of very high shear, particularly in the region close to the wall in the boundary layer. The response equations used to evaluate flow characteristics from the anemometer signals are presented. Operating features such as frequency response, aximuthal yaw sensitivity, signal-to-noise, and stability are discussed and comparisons are made with those of an x-probe. Measurements in turbulent air flow using a hot-wire, x-probe, and split-film probe are presented and the performance of the latter is discussed. The results show that the split-film probe is a promising device for measuring two-dimensional turbulence information, particularly when high transverse spatial resolution is required. However, until improvements can be made, adequate frequency response should be verified by the experimenter for each flow regime of anticipated use.

Meeting Name

Symposium on Turbulence in Liquids (1971: Oct. 4-6, Rolla, MO)


Chemical and Biochemical Engineering

Document Type

Article - Conference proceedings

Presentation Type

Contributed Paper


New Measurement Techniques

Document Version

Final Version

File Type





© 1972 University of Missouri--Rolla, All rights reserved.