Amodel centrifugal fan is tested to deliver 500 cfm of air at standard condition with a pressure rise of 2 in. of water at a speed of 1800 rpm. while the prototype fan will produce the same pressure at 1200 rpm, determine the diameter ratio and the flow rate of the prototype fan

Compute the pressure drop of 30°c air flowing with a mean velocity of 8 m/s in a circular sheet-metal duct 300 mm in diameter and 15 m long. use a friction factor, f 0.02, and pair = 1.1644 kg/m a. 37.26 pa b. 25.27 pa n c. 29.34 pa d. 30.52 pa

To design a steam turbine to produce 12,000 hp power. a engineer comsiders using a steady state stean low st 1160fr and engineer considers using a steady state steam flow at 1160°r and 450 psia to drive this steam turbine. the exhaust of the steam is cooled by the lake (vacuum). heat losing to the surroundings is measured at a rate of 555.55 btu/s. (a) sketch the system with the given conditions. (b) neglecting kinetic and potential energy changes from inlet to exit, determine the volumetric flow rate of the steam at the inlet, (ft'/hr). must clearly show unit conversions at crtical terms.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg. a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?