Example 3.7: A commercial steel piping system is delivering water at 30°C from pressurized tank A to pressurised tank B as shown in figure below. The internal diameter of the pipe is 2.25 cm. The piping system has a well rounded inlet, 1/4 open gate valve, four 90° flanged bend, two 90° miter bend (with vane) and a sharp exit. The total pipe length is 300 m. Gauge pressure at tank A is 500 bar. If the elevation difference, h is 100 m and water is delivered at 250litre/min. Determined minor losses and gauge pressure at tank B

1. Use Laplace transforms to solve the following differential equations for ?(?) for ? ≥ 0. Use ?(0) = 0 and ?̇(0) = 1 for each case.

i. 0 = ?̈(?) + 2?̇(?) + 4?(?)

ii. 0 = ?̈(?) + 3?̇(?) + 2?(?)

iii. 5 = ?̈(?) + 5?̇(?) + 6?(?)

3. For the three differential equations from problem one determine the steady-state value of the system using:

a. lim?→0 ??(?),

b. lim ?→∞ ?(?) analytically,

c. lim ?→∞ ?(?) using MATLAB

Please solve #3 and show MATLAB code

Q1/ Answer the following:
1. What is the main advantage of direct acting thermostats?
2. What is the purpose of using a capacitor in a two-phase reversible induction motor?
3. What does the controller circuit consist of?
4. what is the pressure equalizing connection and when it is used?
5. What does the damper loss coefficient depend upon?
Q2/ Answer the following:
1. What should the damper motor power overcome?
2. What is the function of the starting relay?
3. What are two techniques used for defrost purposes in automatic defrost refrigerator.
4. How is the cooling plate heater connected?
5. What is the function of the super switch in the domestic deep freezer?

Air enters a compressor operating at steady state with a pressure of 14.7 lbf/in.2, a temperature of 70°F, and a volumetric flow rate of 500 ft3/min. The air velocity in the exit pipe is 700 ft/s and the exit pressure is 133 lbf/in.2 If each unit mass of air passing from inlet to exit undergoes a process described by pv1.34 = constant, determine (a) the exit temperature, in °F, and (b) the diameter of the exit pipe, in inches.

. On the Structures, Strengthening, and Heat Treatment of metal alloys:

A. Explain the role of the solute and solvent of a solid solution?

Explain five heat-treatment methods used for metal and alloys?

1. What often happens to safety issues during union negotiations?

2. Who is allowed to accompany an OSHA inspector during an OSHA inspection?

3. What are the two types of variances and when might a company be issued each of them?

4. Name the 4 exemptions to labeling requirements

5. what are the two requirements for a business to fall under OSHAs regulations

6. what records is an employer required to keep concerning toxic chemicals?

7. who typically issues a citation if necessary after an inspection?

8. What are the 3 ways that an employer can provide the required workers compensation coverage for his employees?

9. What is OSHA's stand on safety incentives?

- What materials are ( or can be ) used for adhesives? ( general families)
- What kind of "triggers" are used to cause the "curing" of some polymer adhesives?
- What geometries are "best" for adhesively bonded joints ? What are their names, what do they look like, Why are they "best"?
- When should you choose a material for a new product?
- What criteria do you need to consider in material selection?
- How often should you review the materials and processes for an existing product?

One method for reducing the pumping work in throttled spark-ignition engines is early intake valve closing (EIVC). With EIVC, the inlet manifold is held at a pressure pi, which is higher than the normal engine intake pressure pi*. The intake valve closes during the intake stroke. The trapped fresh charge and residual is then expanded to the normal cycle (lower) intake pressure, pi*. You can assume that both cycles have the same mass of gas in the cylinder, temperature and pressure at state 1 of the cycle.

a) Sketch a p-V diagram including both the standard and EIVC cycle. On the p-V diagram, shade the area that corresponds to the difference of pumping work between the standard and EIVC cycles.

b) What value of intake pressure pi and VEIVC will give the maximum reduction in pumping work for the EIVC cycle?

c) Derive an expression for this maximum difference in pumping work between the normal cycle and the EIVC cycle in terms of pe, pi*, Vc and Vm. Justify any assumptions you make.

what are the things to do before, during, after    operation of mechanical rice transplanter ( walk behind type)

Using your understanding of how plastic deformation occurs, explain briefly each of the following ways to strengthen metallic materials

a. strain strengthening (work hardening)

b. alloy strengthening

c. grain boundary strengthening

It is desired to produce liquefied natural gas (LNG), which we consider to be pure methane, from that gas at 1 bar and 280 K (conditions “1” in the Linde process of the diagram). Leaving the cooler (“enfriador”) methane is at 100 bar and 210 K. The flash drum (“separador”) is adiabatic and operates at 1 bar. The recycled methane leaving the heat exchanger is at 1 bar and 200 K. The compressor can be assumed to operate reversibly and adiabatically. However, because of the large pressure change, a three-stage compressor with intercooling is used. The first stage compresses the gas from 1 bar to 5 bar, the second stage from 5 bar to 25 bar, and the third stage from 25 bar to 100 bar. Between stages the gas is isobarically cooled to 280 K.

(a)For each point in the Linde diagram write the conditions you know, and find the corresponding points in the H-P diagram for methane.

(b)Calculate the fractions of vapor and liquid leaving the flash drum.

(c)Calculate the amount of compressor work required for each kg of LNG produced.

Compare the bending moment diagrams of the indeterminate and simply supported beams. What are the advantages of using indeterminate beams? Why are thereactions different from those of the simply suppored beam with similar loading

A regenerative gas-turbine power plant with two stages of compression and two stages of expansion operates on a Brayton cycle with a pressure ratio across the two-stage compressor of 12. Air enters the first stage of the compressor at 100 kPa and 300 K. At the intercooler exit, the temperature is 300 K. In both turbine stages, air enters at 1400 K. The total heat transfer rate to the air in both combustors is 5,000 kW. The regenerator has an efficiency of 70%, both compressor stages have an isentropic efficiency of 75%, and both turbine stages have an isentropic efficiency of 80%. The pressure in the intercooler and reheater is 600 kPa. Using an Air Standard Analysis, find the following

(a) Thermal Efficiency in Percentage
(b) net work output
(c) mass flow rate
(d) Intercooler/Reheater pressure that maximizes the cycle's thermal efficiency
(e) Max Work output