Transient Line-Source Apparatus for Thermal Conductivity Determination of Fluids at 295-600K and 1-700 Bars
A transient hot-wire apparatus was developed for rapid and accurate determination of the thermal conductivity of fluids in the range of 295-600 K and up to 700 bars.
A 12.7 micron diameter platinum wire with spot-welded potential leads was used for measurements in the 295–600 K range. A computerised data acquisition system using an on-line microprocessor (LSI-11) and analog data-multiplexer was developed for fast and accurate recording of measurements and immediate data processing to obtain the thermal conductivity. Measurements obtained with this apparatus have been reported for many fluids. The reproducibility and accuracy of measurements are estimated to be within 0.5 and 2 percent, respectively.