Direct calculation of mean radiant temperature using radiant intensities

Conference · Sat Jul 01 04:00:00 EDT 2000

OSTI ID:20104809

Palmer, J M; Chapman, K S

This paper develops and compares a new method for calculating the local mean radiant temperature to experimental data and the classical method described by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (1997). The new method calculates the mean radiant temperature directly from the radiant intensity field at a particular point in the room. This approach, using the localized radiant intensity field, was theorized to be more accurate and flexible than using radiosities or surface temperatures and view factors currently described in the ASHRAE Handbook (1997). To benchmark the accuracy of the new method for calculating the mean radiant temperature, both methods of calculating the mean radiant temperature were compared to experimental measurements taken under carefully monitored conditions. The purpose of this process was to compare the classical and radiant intensity methods of mean radiant temperature calculation. From the four comparisons presented in this paper, using the radiant intensity field directly for the mean radiant temperature portion of the operative temperature calculations gave results 1--2 C (2--3 F) different from the classical method using view factors and surface temperatures and the experimental measurements. The radiant intensity method is a refinement to the mean radiant temperature calculation, enabling a direct solution of the radiant transfer equation that can handle extreme boundary conditions.

• Research Organization: National Inst. of Standards and Technology, Gaithersburg, MD (US)
• OSTI ID: 20104809
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AMBIENT TEMPERATURE
BOUNDARY CONDITIONS
CALCULATION METHODS
COMPARATIVE EVALUATIONS
MATHEMATICAL MODELS
RADIANT HEAT TRANSFER
THERMAL COMFORT