Question

Consider a spherical tank containing a fluid which loses heat (q) to the outside fluid. In the absence of any insulation (i.e.r-ro), the heat loss rate is given by qm. However, when insulation is provided, the heat loss increases with the thickness of the insulating layer and reaches a maximum at re (the critical radius of insulation given by 2kins/ho). With a further increase in insulation, heat loss decreases and equals qm when the insulation thickness provided equals (rmin ro) as shown in the figure below. Using the information provided in the problem, find an expression for rmin in terms of re and ro n terms of re and ro- ro rc min

Answer 1

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