Studies of a hot-wire anemometric probe for the measurement of two-dimensional components and sense of a velocity vector

摘要

Three types of hot-wire anemometric probes for the measurement of a two-dimensional flow velocity vector and its sense are presented in this paper. Such probes are a modification of type X hot-wire probes, in which additional supports are introduced in the middle of wires. The idea of the sense of a flow velocity vector assessment is based on the phenomenon of the temperature distribution asymmetry upon the wire placed askew with respect to the flow sense. The temperature distribution asymmetry is underlined by the flow direction- and sense-dependent heat energy transfer occurring within the wire. The measurement of the voltage difference between both halves of the wire is used for the detection of the flow sense. The voltages on whole wires are used for the determination of the flow velocity vector components. For such purposes, a modification of the measuring algorithm used for the type X hot-wire probes was used. The results from testing of measuring probes which were developed are presented and their metrological properties are discussed.