DOE-2 Reference Manual Version 2.1 - DOE2.com

INF-COEFspecifies an infiltration flow coefficient used to computethe infiltration resulting from cracks in an exterior wallor roof. This entry is required if the crack method(INF-METHOD ; CRACK) is specified in SPACE orSPACE-CONDITIONS.For walls that use response factors to calculate heat flow and thatuse the crack method, the coefficient is used in the followingequation for determining infiltrationwherecfm ; (INF-COEF) * (Pw)0.8 * (A)cfm ;P w ;A ;infiltration airflow (cfm)pressure difference between outsideinside air (inches of water)Wall surface area (ft2)Typical values for INF-COEF are in the following table(Refs. 3 and 5, Chap. 21).andConstruction of Wall13-in. brick with plastered surface13-in. brick, furring, lath and plasterFrame wall, lath and plaster8.5-in. brick-plain16-in. shingles on shiplap wlbuilding paper16-in. shingles on shiplap16-in. shingles on 1 by 4 boards on5-in. center(0.01)(0.03)(0.09)(5.0)(0.5)(8.0)(40.0)INF-COEF0.0020.0050.0160.9150.0921.4657.324The values in parentheses are typical infiltration values incfh/ft2 for a 7.5 mph wind normal to the surface of thegiven walls (7.5 mph equals approximately .05 inches of water).For walls using the steady-state (U-value) method for heatflow calculation and the crack method, the following equationis used:cfmwhere now; (INF-COEF) * (Pw)0.5 * (L)L ; crack length (ft).Typical values for INF-COEF are in the following table (Refs.3.and 5, Chap. 21).II 1.101 (Revised 5/81)