The measurement of the turbulent shear stresses and normal and by-normal intensities with a hot-wire anemometer requires that the direc-tional sensitivity of the hot-wire be known. Normal component or cosine law cooling is generally assumed, although for finite wire lengths the nonuniform wire temperature must- cause a deviation from the cosine law.nThere is disagreement in the literature as to the directional sensitivity of a hot-wire and, therefore, to the accuracy of measurements made with wires oblique to the flow when cosine law cooling is assumed. The present investigation was undertaken to determine accurately the directional sensitivity of a hot-wire, the causes of any observed depar¬tures from normal component cooling and the errors in selected turbulence quantities which would be caused by the assumption of normal component cooling.
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