Experimental Investigation of Void Fraction During Horizontal Flow in Larger Diameter Refrigeration Applications

EXPERIMENTAL INVESTIGATION OF VOID FRACTION DURING HORIZONTAL FLOW IN LARGER DIAMETER REFRIGERATION APPLICATIONS Michael Jay Wilson Department of Mechanical and Industrial Engineering University oflllinois at Urbana-Champaign, 1998 Ty Newell and John C. Chato, Advisors Void fractions were measured for R134a and R410A for a smooth tube with inside diameter of 6.12 mm (0.241"), an axially grooved tube of base diameter 8.89 mm (0.350"), and a 18° helically grooved of base diameter 8.93 mm (0.352"). The experiment covered mass fluxes from 75 kg/m2s to 700 kg/m2s (55 515 klbnJ'ft2-hr) and average test section qualities from 5% to 99% with an inlet temperature of 5°C (41°F). Several existing models are examined for accuracy and a simple adjusted model is presented to accurately predict the data and data presented in a companion study by Yashar[1998]. The experimental apparatus and methodology are also discussed.

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