Relation Between Wire Resistance and Fluid Pressure in the Transient Hot-Wire Method
نویسندگان
چکیده
The resistance of metals is a function of applied pressure, and this dependence is large enough to be significant in the calibration of transient hot-wire thermal conductivity instruments. We recommend that for the highest possible accuracy, the instrument's hot wires should be calibrated in situ. If this is not possible, we recommend that a value of γ, the relative resistance change with pressure, of -2×10-5 MPa-1 be used to account for the pressure dependence of the platinum wire's resistance.
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