In an adiabatic flow of a perfect gas in a constant- area duct with friction, we have the inlet condition as M1 = 2.0, p1 = 25 kPa, T1 = 250 K. The duct length-to-(hydraulic) diameter ratio is L/Dh = 10.262 and the average friction coef- ficient at the wall is Cf = 0.005. Assuming gas properties are = 1.4 and R = 287 J/kg⋅K, calculate

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.

What is creep? what is stress relaxation?

An engine, weighing 3000 n, is supported on a pedestal mount. it has been observed that the engine induces vibration into the surrounding area through its pedestal at the maximum operating speed. determine the stiffness of the dynamic vibration absorber spring in (n/m) that will reduce the vibration when mounted on the pedestal. the magnitude of the exciting force is 250 n, and the amplitude of motion of the auxiliary mass is to be limited to 2 mm note: in this question type-in right numbers, no decimals, no fractions, no unit. approximate to right number if needed