Labels:anechoic chamber | bulletin board | shelf | sky OCR: Standard 500-L Louvers Three main factors affect Free Area FA Blade angle Bigger illustration ion the Blade spacing following slide Blade overlap Blade angle has the most direct impact on FA Other factors that affect FA: Size of louver-i. X A louver will have different FA than a2'X2 Jouver of the same blade configuration. The re ason for this that the FA includes the frame the head sill and iambs the smaller the louver opening the greater percentage of the overallis 'frame" and therefore there 19 less area through which air can pass Some manufacturers in US and Europe do not use the AMCA method of measuring free area and only consider the space between the blades at the front Therefore their free areas are higher than manufactur ers who follow the AMCA method illustr impaci openi entage ar ...
