Water (c= 4180 j/kg. °c) is to be heated by solar heated hot air (cp = 1010 j/kg•°c) in a double-pipe counterflow heat exchanger. air enters the heat exchanger at 90°c at a rate of 0.3 kg/s, while water enters at 22°c at a rate of 0.1 kg/s. the overall heat transfer coefficient based on the inner side of the tube is given to be 80 w/m.°c. the length of the tube is 12 m and the internal diameter of the tube is 1.2 cm. determine the outlet temperatures of the water and the air.( 27.3°c, 82.7°c)

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.