An airship is to operate at 20 m/s in air at standard conditions (rho = 1.225 kg/m3, p = 101,300 Pa). A model is constructed to 2 scale and tested in a variable-pressure wind tunnel at the same air temperature to determine the drag.

a) What criterion should be used to determine dynamic similarity? (You may assume that roughness is not important for this problem.)

(b) If the model is tested at 20 m/s, what pressure should be used in the wind tunnel?

(c) If the model drag force is found to be 250 N, what will be the drag of the full-scale airship?

Water at 70°f and streams enter the mixing chamber at the same mass flow rate, determine the temperature and the quality of the exiting stream. 0 psia is heated in a chamber by mixing it with saturated water vapor at 20 psia. if both streams enters the mixing chamber at the same mass flow rate, determine the temperature and the quality of the existing system.

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10

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.