Puestion 4-8 Ques
The velocity components for a flow of an incompressible fluid are given by the following
equations:
u=kx (y + z);
v=ky (x + z);
w=-k z(x + y)- z^.
• Determine the value of “k” in order to have a physically possible flow.
• Determine if the flow is steady or not (use the value of “K”, obtained in the first part).
• Determine if the flow is uniform or not (use the value of “K”, obtained in the first part).
• Determine if the flow is rotational or not (use the value of “k”, obtained in the first part). If it
is a rotational flow, compute the magnitude of rotations at a point A which has the following
coordinates: x=1, y=1, z=1.

Acommercial grade cubical freezer, 4 m on a side, has a composite wall consisting of an exterior sheet of 5.0-mm thick plain carbon steel (kst= 60.5 w/m k), an intermediate layer of 100-mm thick polyurethane insulation (kins 0.02 w/m k), and an inner sheet of 5.0- mm thick aluminium alloy (kal polyurethane insulation and both metallic sheets are each characterized by a thermal contact resistance of r 2.5 x 104 m2 k/w. (a) what is the steady-state cooling load that must be maintained by the refrigerator under conditions for which the outer and inner surface temperatures are 25°c and -5°c, respectively? (b) for power saving purpose, which wall material should be increased/reduced in. thickness in order to reduce 50% of the cooling load found in part (a)? redesign the thickness of the proposed material. 177 w/m-k). adhesive interfaces between the q=575.93 w