ASHRAE-Standard-55 - Page 032

Extracted Content

Figure C-1 Fraction of sky vault in occupant’s view ( fsvv ).

Table C-1 Symbols and Units

Symbol Description Unit

ERF Effective radiant field W/m [2]

feff Fraction of body surface exchanging radiation with surroundings hr Radiation heat transfer coefficient W/m [2] ·K

ta Air temperature °C

 LW Average long-wave radiation absorptivity of body (0.95)  SW Average short-wave radiation absorptivity of body ERF solar Effective radiant field solar component W/m [2]

Esolar Total short-wave solar radiant flux W/m [2]

Edir Direct-beam component of short-wave solar radiant flux W/m [2]

Ediff Diffuse component of short-wave solar radiant flux W/m [2]

Erefl Reflected component of short-wave solar radiant flux W/m [2]

fsvv Fraction of sky vault exposed to body Tsol Window system glazing unit plus shade solar transmittance Idir Direct solar beam intensity W/m [2]

Idiff Diffuse solar intensity W/m [2]

ITH Total horizontal solar intensity W/m [2]

fp Projected area factor fbes Fraction of body surface exposed to sun  Solar altitude angle deg

SHARP Solar horizontal angle relative to front of person deg

Rfloor Floor reflectance (fixed at 0.6)

Posture (seated, standing, or horizontal)

30 ANSI/ASHRAE Standard 55-2023