ASHRAE-Standard-55 - Page 043

Extracted Content

var ICLS = IMS * CHCS/CTCS * (1 - FCLS)/(CHCS/CTCS - FCLS * IMS); var RAS = 1.0/(FACLS * CTCS); var REAS = 1.0/(LR * FACLS * CHCS); var RECLS = RCLS/(LR * ICLS); var HD_S = 1.0/(RAS + RCLS); var HE_S = 1.0/(REAS + RECLS);

//SET determined using Newton’s iterative solution

var DELTA = .0001; var dx = 100.0; var SET, ERR1, ERR2; var SET_OLD = TempSkin - HSK/HD_S; //Lower bound for SET while (Math.abs(dx) > .01) { ERR1 = (HSK - HD_S * (TempSkin - SET_OLD) - W * HE_S *

(PSSK - 0.5 * FindSaturatedVaporPressureTorr(SET_OLD))); ERR2 = (HSK - HD_S * (TempSkin - (SET_OLD + DELTA)) - W * HE_S *

PSSK - 0.5 * FindSaturatedVaporPressureTorr((SET_OLD + DELTA))); SET = SET_OLD - DELTA * ERR1/(ERR2 - ERR1); dx = SET - SET_OLD; SET_OLD = SET; } return SET; }

ANSI/ASHRAE Standard 55-2023 41