Temperature dependence of the thermal conductivity of liquid water is important in several engineering applications. This study reports experimental measurements of the thermal conductivity of water as a function of temperature. The transient hot-wire method is used for measurement of the thermal conductivity over the temperature range of 273-305 K at atmospheric pressure conditions. The experiments are carried out for a fixed current of 250 mA, and the resulting temperature rise for a platinum wire 9.53 cm long with a radius of 25 mu m yields the thermal conductivity by means of the solution to the heat conduction equation for a continuous line source in an infinite medium. It is found that using the temperature-dependent coefficient of resistance of platinum wire is crucial in obtaining the correct variation of the thermal conductivity with temperature. A data reduction procedure is suggested for improvement of the accuracy of the reported values via identification of the onset of convection in the fluid. The specific contributions of this work include the extension of experimental results to lower temperatures in the vicinity of the freezing point of water. This study also provides systematic comparison of experimental and computational results, which helps understand the fluid flow and heat transfer characteristics in the vicinity of a line source embedded in an infinite fluid medium.
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