An air-cooled steam condenser is operated with air in cross flow over a square, in-line array of 400 tubes ( 20), with an outside tube diameter of 20 mm and longitudinal and transverse pitches of 60 mm and 42 mm, respectively. Saturated steam at a pressure of 2.455 bars enters the tubes, and a uniform tube outer surface temperature of 390 K may be assumed to be maintained as condensation occurs within the tubes. (a) If the temperature and velocity of the air upstream of the array are 300 K and 7 m/s, what is the temperature of the air that leaves the array

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.