Frederick Schwartz MS Graduate Student Room/Office: 1335 Email: fschwartz@wisc.edu From: Fort Atkinson, WI Undergraduate: ME, UW-Platteville ‘08 Thesis: Development of Predictive Correlations for Thermal-Fluid Behavior of Mixed Refrigerants (ASHRAE Project 1602)

Experimental Significance Mixed refrigerants have a thermodynamic advantage when compared to pure fluids for Joule-Thompson refrigeration cycles Accurate prediction of thermal-fluid behavior is critical to design of cryogenic systems No practical correlations currently exist for thermal-fluid behavior of mixed refrigerants at cryogenic temperatures for use in equipment design

Test Facility Design Tout Tin Twall Test Section gas mixture ASHRAE Testing Requirements: Six Refrigerant Concentrations R14 (35% ), R23 (15% ), R32 (15% ), and R134a (35% ) Diluted with Argon (0%, 20%, 40%) Methane (45%) , Ethane (35%) , and Propane (20%) Diluted with Nitrogen (0%, 20%, 40%) Mass flux: 250 kg/m2-s Heat flux: 10 kW/m2 Temperatures: 150 K to room temperature Pressures: 100kPa, 1000 kPa Tube diameters: 0.5, 1.5, & 3.0 mm Minimize convection and radiation heat transfer around test section Twall Tin Tout Test Section gas mixture

Research Objectives Obtain thermal-fluid behavior data from the ASHRAE specified test conditions using the test facility developed for this project Develop predictive, semi-empirical correlations for use in refrigeration equipment design