A dormitory at a large university, built 50 years ago, has exterior walls constructed of L s

Question:

A dormitory at a large university, built 50 years ago, has exterior walls constructed of L= 25-mm-thick sheathing with a thermal conductivity of ks = 0.1 W/m · K. To reduce heat losses in the winter, the university decides to encapsulate the entire dormitory by applying an Li = 25-mm-thick layer of extruded insulation characterized by k= 0.029 W/m · K to the exterior of the original sheathing. The extruded insulation is, in turn, covered with an L= 5-mm-thick architectural glass with k= 1.4 W/m · K. Determine the heat flux through the original and retrofitted walls when the interior and exterior air temperatures are T∞,i  = 22°C and T∞,o = –20°C, respectively. The inner and outer convection heat transfer coefficients are h= 5 W/m2  · K and h= 25 W/m2  · K, respectively.

Fantastic news! We've Found the answer you've been seeking!

Step by Step Answer:

Related Book For  book-img-for-question

Fundamentals Of Heat And Mass Transfer

ISBN: 9780470501979

7th Edition

Authors: Theodore L. Bergman, Adrienne S. Lavine, Frank P. Incropera, David P. DeWitt

Question Posted: