ASHRAE-Standard-55 - Page 036
Extracted Content
[0.288,0.332,0.298,0.29,0.264,0.222,0.177],
[0.274,0.326,0.294,0.289,0.252,0.214,0.177],
[0.254,0.308,0.28,0.276,0.241,0.202,0.177],
[0.23,0.282,0.262,0.26,0.233,0.193,0.177],
[0.216,0.26,0.248,0.244,0.22,0.186,0.177],
[0.234,0.258,0.236,0.227,0.208,0.18,0.177],
[0.262,0.26,0.224,0.208,0.196,0.176,0.177],
[0.28,0.26,0.21,0.192,0.184,0.17,0.177],
[0.298,0.256,0.194,0.174,0.168,0.168,0.177],
[0.306,0.25,0.18,0.156,0.156,0.166,0.177],
[0.3,0.24,0.168,0.152,0.152,0.164,0.177]]; } var fp11 = fp_table[sharp_i][alt_i]; var fp12 = fp_table[sharp_i][alt_i+1]; var fp21 = fp_table[sharp_i+1][alt_i]; var fp22 = fp_table[sharp_i+1][alt_i+1]; var sharp1 = sharp_range[sharp_i]; var sharp2 = sharp_range[sharp_i+1]; var alt1 = alt_range[alt_i]; var alt2 = alt_range[alt_i+1];
//Bilinear interpolation fp = fp11 * (sharp2 - sharp) * (alt2 - alt); fp += fp21 * (sharp - sharp1) * (alt2 - alt); fp += fp12 * (sharp2 - sharp) * (alt - alt1); fp += fp22 * (sharp - sharp1) * (alt - alt1); fp /= (sharp2 - sharp1) * (alt2 - alt1); return fp; }
function ERF(alt, sharp, posture, Idir, tsol, fsvv, fbes, asa){
/* ERF function to estimate the impact of solar radiation on occupant
comfort
INPUTS:
alt: altitude of sun in degrees [0, 90] sharp: sun’s horizontal angle relative to person in degrees [0,
180] posture: posture of occupant (‘seated’, ‘standing’, or ‘horizon
tal’) Idir: direct beam intensity (normal) tsol: total solar transmittance (SC * 0.87) fsvv: sky vault view fraction: fraction of sky vault in occupant’s
view [0, 1] fbes: fraction body exposed to sun [0, 1] asa: average shortwave absorptivity of body [0, 1] (alpha_sw) */ var DEG_TO_RAD = 0.0174532925; var hr = 6; var Idiff = 0.2 * Idir; var fp = get_fp(alt, sharp, posture);
if (posture'standing' || posture ‘horizontal’){
var feff = 0.725; } else if (posture==‘seated’){
var feff = 0.696; } else {
console.log(“Invalid posture (choose seated or seated)”); return; }
var sw_abs = asa; var lw_abs = 0.95;
34 ANSI/ASHRAE Standard 55-2023