Mechanical Engineering Answers

Calculate the capacity of a fuel tank and the fuel pump capacity of a Diesel power plant with

5500 kw installed capacity and 50% plant capacity factor. You have to procure fuel monthly with

150% contingency.

A Dodecane fuel will be used in an IC Engine. The Air-Fuel ratio is 30:1. Calculate the percent

excess air.

5. Two shafts 30 in. apart, each carrying a four-step pulley, are to be connected by a cross belt. The driving shaft is to turn 180 rpm while the driven shaft is to turn 50, 150, 250, and 600 rpm. The smallest step of the driver is 10 in. in diameter. Find (a) the diameters of all the steps, (b) angle of contact for each pair of pulleys, and (c) belt length.

4. A pulley 600 mm. in diameter transmits 40 kW at 500 rpm. The arc of contact between the belt and pulley is 144° having a center distance of 1100 mm. Determine: (a) diameter of the driven pulley for open belt drive, (b) speed of the driven pulley, and (c) belt length for open belt connection.

Drive pulley A with a diameter of 200 mm , drives pulley B with a diameter of 800 mm by means of a belt drive. IF pulley B is uniformly accelerated from 69 r/min to 240 r/min calculate

(a) The angular acceleration of each pulley

(b) The linear acceleration of the belt if slip is ignored

(C) The initial velocity of pulley A in r/min and the final velocity of pulley A in rad/s.

17. The moisture removed from a material is 200 lb/hr and change of humidity ratio in dryer is 0.015. Determine the fan capacity if specific volume of air entering is 38 ft3/lb. Please the answer with solution.

16. Find the dew point temperature of air whose humidity ratio is 0.0150 kg water/kg dry air. Please the answer with slution.

14. A cooling tower cools water from 39oC to 24oC at the rate of 25 kg/s. Air enters the tower at 18oC at the rate of 35 kg/s. Find the temperature of air leaving the tower. Please explain the answer with solution.

12. A 120 tons refrigeration system with COP of 5 has a condenser which is to be cooled by means of a cooling tower. Air enters the tower at 25oC db and 50% RH and leaves at 35oC db and 80% RH. Find the volume of air needed m3/hr. At 25oC and 50% RH: h = 50 KJ/kg, v = 0.86 m3/kg At 350C db and 80% RH: h = 108

17. The moisture removed from a material is 200 lb/hr and change of humidity ratio in dryer is 0.015. Determine the fan capacity if specific volume of air entering is 38 ft3/lb. Explain the answer..