Menu
Home / Mechanical Engineering / Heat and Mass Transfer :: Discussion

Discussion :: Heat and Mass Transfer

  1. Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be

    2. A.

     One
    B.

     Two
    C.

     Three
    D.

     Four

    View Answer

    Workspace

    View Answer

    Answer : Option C

    Explanation :

    Q with shield/Q without shield = 1/n+1. N = no.of parallel shields. 0.25n+0.25 = 1. 0.25n = 0.75. n = 3.

Write your comments here:

Be The First To Comment