Engineering Answers

26. An auditorium seating 1600 people is to be maintained at 80oF dry bulb and 65oF wet bulb temperature

when outdoor air is at 91oF dry bulb and 75oF wet bulb. Solar heat load is 120,000 Btu/hr and supply air is

at 60oF, determine the amount of supply air. (Use sensible heat load of 225 Btu/hr per person).

Dimension of susceptibility is

1/ Coulomb

Coulomb^2

It is dimensionless

None of the above

(1) Describe the composition of fabrication

(2) Describe the physical properties of fabrication

(3) Describe the mettods of fabrication

A vibration damper unit is composed of a rubber cylinder of diameter d compressed inside of a wrought-iron cylinder by a force F applied to the steel rod. Develop, in terms of d, F, and Poisson’s ratio ν for the rubber, the following expression for the lateral pressure p between the rubber and the wrought-iron cylinder.

Compute the value of 𝑝 for the following data: 𝑑 = 63.5 𝑚𝑚, 𝜈 =

0.5, 𝑎𝑛𝑑 𝐹 = 9 𝑘𝑁.

5. Compute for the enthalpy, internal energy, and entropy of steam at 72oC and 93%

quality.

10. A supercritical power generates steam at 25 Mpa and 560℃. The condenser pressure is 7 kpa. Determine

the exit quality of steam if it expands through a turbine in this power plant.

9. Steam enters a turbine at 1.4 Mpa and 320℃. The turbine internal efficiency is 70%, and the total requirement is 800 kw. The exhaust is to the back pressure system, maintains at 175kpa. Find the stean flow rate.

8. A steam power plant operates on the Rankine cycle. The steam enters the turbine at 7 Mpa and 550℃ with a velocity of 30 m/s. it discharges to the condenser at 20 kpa with a velocity of 90 m/s. Calculate the net work in kw for a flow of 37.8kg/s.

7. A superheat steam Rankine cycle has turbine inlet conditions of 17.5 Mpa and 530℃ expands in a turbine to 0.007 Mpa. The turbine and pumps polytropic efficiencies are 0.9 and 0.7 respectively, pressure losses between pump and turbine inlet are 1.5 Mpa. What should be the pump work in KJ/kg?

6. A throttling calorimeter is connected to the superheated steam line supplying steam to the auxiliary feed pump on a ship. The line pressure measures 2.5 Mpa. The calorimeter pressure is 110 kpa and 150oC. Determine the entropy of the steam line.