For a two dimensional incompressible flow in a square domain 0 <= x <= 2Ï€ and 0 <=y <= 2Ï€ of u(x, y)= sin (x cos(y) and y and component of velocity v (x, 0) at the lower boundary y =0. Required:
a. Find the expression of v(x, y)
b. Find the stream function for this flow.
c. Does the potential function φ exist for this flow, show your proof.
d. Show that the velocity field is NOT a valid solution of Navier-Stoke equation.

On a average work day more than work place firs are reorted

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Different types of steels contain different elements that alter the characteristics of the steel. for each of the following elements, explain what the element does when alloyed with steel.