Forced-convective vaporization of refrigerants in spirally fluted tubes

Conference · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6162445

Panchal, C B; France, D M; Stellman, R S

Subcooled and bulk flow boiling heat transfer were studied experimentally inside of spirally fluted tubes. Forty-eight tests were performed using refrigerant-11 flowing upwards inside the 84 spirally fluted tubes of the test section. The maximum heat supply of 675 kW was provided by steam condensing on the outside of the 4.45 m long aluminum tubes. The mean tube diameter (diameter of a round tube with the same flow area) was 26.77 mm, and flute depth was 1.54 mm at an angle of 30 degrees relative to the tube axis. Experiments were performed with a refrigerant-11 pressure range of 296 to 1010 kPa and mass flux range of 60 to 183 kg/mSs. Test results were analyzed and predictive relations were developed in three sections: local subcooled boiling heat transfer, average bulk boiling heat transfer, and local heat transfer in bulk boiling. The results showed that, on an average basis, the bulk boiling heat transfer coefficient in the spirally fluted tubes was higher than in equivalent flow area round tubes by a factor of 1.8. The relations developed for calculation of local heat transfer coefficients in subcooled and bulk boiling were used to predict heat transfer parameters as a function of test section length. The predicted exit qualities compared well with the data.

• Research Organization: Argonne National Lab., IL (USA); Illinois Univ., Chicago (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6162445
• Report Number(s): CONF-861204-10; ON: DE87011352
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
BOILING
CONVECTION
DATA
ENERGY TRANSFER
EVAPORATION
EXPERIMENTAL DATA
FLOW RATE
FLUIDS
FORCED CONVECTION
HEAT TRANSFER
INFORMATION
MASS TRANSFER
MATHEMATICAL MODELS
NUMERICAL DATA
PHASE TRANSFORMATIONS
REFRIGERANTS
SUBCOOLED BOILING
TESTING
TUBES
WORKING FLUIDS