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Measurement of the Heat Capacities of Pure and Mixed Refrigerants.

pdf icon Measurement of the Heat Capacities of Pure and Mixed Refrigerants. (5936 K)
Radermacher, R.

Thermophysical Properties, 10th Symposium. Proceedings. June 20-23, 1988, Gaithersburg, MD, 1988.


National Institute of Standards and Technology, Gaithersburg, MD


refrigerants; heat capacity; calorimeters; hydrocarbons; liquid phases; vacuum chambers; specific heat; fluids; mixtures


A flow calorimeter was designed and built to measure the heat capacity of pure and mixed halogenated hydrocarbons in the liquid phase. The calorimeter is an electrically heated, coiled tube located inside a vacuum chamber in the water bath. The liquid under investigation is pumped by means of a syringe pump through the calorimeter and then collected in a pressure container located in dry ice to ensure a constant back pressure. The temperature difference is measured with a thermopile made of wire of 0.002 inch in diameter, and the flow rate is determined by weighing of the sample. The calorimeter was calibrated using water, refrigerant 11, refrigerant 22, and ethylene glycol. The measurement error is - 1%. Results are reported for the pure refrigerants R114, R123, R142b and R152a, and the mixtures R22/R114, R22/R142b and R22/R152a.