id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
alkej-696	Ghanim, Mohannad R.; Ahmed, Sabah T.	اختيار افضل موقع لنظام الحاجز الاشعاعي في السقوف المهواة مزدوجة الطبقة	2020	10	.pdf	application/pdf	4639	260	68	Theory The rate of heat transfer per unit area (��) measured from the upper plate is equal to the rate of heat transfer by convection to the air in the cavity and the rate of heat exchange by radiation with the lower plate as follows [13]: �� � �� �� � � �� �� 1 � 1 �� � 1 … �1� Where T and T� are the average temperature of the upper and lower plate respectively in K, σ is the Stefan–Boltzmann constant and it is equal to 5.67 × 10-8 W/m�K�, and ε and ε� are the inner surface emissivity of the upper and lower plate respectively. ��. 1 � ��.� ��.	cache/alkej-696.pdf	txt/alkej-696.txt