Correct Answer: tubes to avoid the expansion of high pressure shell construction.
3. Low pressure steam (with saturation temperature between 105 to 120°C) is usually used in the vacuum evaporators, which normally employ a vacuum of about __________ mm Hg (referred to a 760 mm mercury barometer).
Correct Answer: not less than one-fourth of the tube diameter or 3/16".
7. For annular flow of a fluid, the ratio of the equivalent diameter for pressure drop calculation to the equivalent diameter for heat transfer calculation is
8. In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to
Correct Answer: Liquor flows inside the tube, while the steam is outside submerging the tube.
10. For a cylindrical shell, (subject to the thickness of uppermost course being more than the minimum for diaofthe tank in question), the thickness of the courses of shell
Options
A. decreases upwards.
B. increases upwards.
C. remains same throughout.
D. may decrease or increase upwards depending upon whether vacuum or positive pressure would be maintained inside the shell.