A steam power plant has two turbines in series which together develop a power output of 25MW. The boiler supplies steam at 80 bar, 500°C to the high-pressure turbine in which there is an enthalpy drop of 420 kJ/kg. The exhaust from the high pressure is at a pressure of 15 bar, at which pressure some of the steam is delivered to an open-type feedwater heater while the remainder is reheated to 450°C. The steam from the reheater is expanded in the low-pressure turbine to a condenser pressure of 0.05 bar and 0.92 dryness fraction. The condensate leaves the condenser at 25°C and is pumped into the feedwater heater at 15bar where it mixes with the bled steam from the high-pressure turbine exhaust. The feedwater leaves the heater at 188°C and is pumped into the boiler. You may neglect the feed pump work.
Calculate the mass flow rates through the high and low-pressure turbines
In: Mechanical Engineering
(Manufacturing Technology)
1. Do a summary what happen to titanic in the aspect of material(body) and the ductile brittle temperature(DBT) of the material
In: Mechanical Engineering
Use Matlab to write the following
1. Write code to determine whether a year is a leap year. Use the mod function. The rules for determining leap years in the Gregorian calendar are as follows:
All years evenly divisible by 400 are leap years.
Years evenly divisible by 100, but not by 400, are not leap years.
Years divisible by 4, but not by 100, are leap years.
All other years are not leap years.
For example, the years 1800, 1900, 2100, 2300 and 2500 are not leap years, but 2400 is a leap year.
2. Solve the following:
a. Use a for loop to determine the sum of the first 10 terms in the series 5k3, where k=1,2,3,...,10. Report your answer to the Command Window.
b. Repeat part (a) without using a loop.
In: Mechanical Engineering
What are the disadvantages and advantages of meter-out and meter-in flow control valves?
In: Mechanical Engineering
Manufacturing Technology
1. Find out at least 3 types method to produce for powder technology
2. Hot Pressing Forming(HPF)
(i) What is that
(ii) How its work
3. What mean by surface energy in sintering
4. What do you mean by inpregnated and infiltration
In: Mechanical Engineering
What are the similarities and differences with AutoCAD and Solid Works?
Any pros or cons to using AutoCAD over other programs?
In: Mechanical Engineering
Manufacturing Technology
1.
(a) why the injection molding required the reciprocating screw?
(b) why moving forward and backward
2. glass
(a)melting point
(b) process in producing glass
3. Thermoforming
(at least 5) :
(a) material
(b) application
(c) how its work
In: Mechanical Engineering
Depreciation scenario Your organisation has decided to purchase an item of equipment expected to work 1700 hours per year (average) for a 12 year working life. (a) Discuss, in about 200 words, two methods you could use to compare alternative options when buying this equipment. (b) Assume that the item of equipment you decided to purchase had a purchase price of $2,900,000 and a residual value at the end of 12 years of $260,000. Tabulate the depreciation and book value for the life of the item by each of the following methods: 1) straight line 2) declining balance 3) sum of digits. (c) Tabulate details of a sinking fund to accumulate to the original purchase price less residual value assuming an interest rate of 6%. (d) Draw a graph showing the book values in each of the above (plotted on the same graph for comparison). (e) Comment on the factors that an equipment owner might consider when selecting one of these methods. (f) Assume now that you have purchased this equipment. What is the Total Annual payment required for operating the equipment? You have the following additional data: • Maintenance costs are $60,000 in the first year • Operator wages are $100,000 in the first year • Storage, transport and other miscellaneous costs are $15,000 in the first year • Money costs 8% per year Hint: Start by calculating the Capital Recovery Factor (g) Maintenance, operator and miscellaneous costs are expected to increase at a flat rate of 4% per year over the life of the machine. Based on a Profit margin of 32%, create a table that calculates the hourly charge out rate, including profit, you would need for its hire during each year of the working life of the equipment. (h) Also based on this hourly charge and expected operating hours, what is the expected annual income over the working life of the equipment?
In: Mechanical Engineering
In: Mechanical Engineering
You are the head of the engineering department in a certain company. your department has been allocated an annual budget of R2.6 million for this year. it is now towards the endof the financial year and your department has overspent by 25%. your senior manager wants you to justify why this is so. YOur task is to present a report showing all the expense of your department for the year and analyse them in a form of a Pareto analysis and a drill down analysis. in your analysis, ensure that you highlight the cause of your over expenditure, including the failure modes of the equipment. Justify ypur financial over spend with things that affect maintenance such as economic factors (macro and micro), poor workmanship from contractors, shift arrangements, poor quality spares, emergency work that had to be done
In: Mechanical Engineering
Determine which of the following sets of data satisfy the first law of thermodynamics? (Recall that E = total energy = U + KE + PE)
a. W = 50 kJ Q = 170 kJ DeltaE = 120 kJ
b. W = 100 Btu Q = -110 Btu DeltaE = -210 Btu
c. W = 250 kJ Q = -110 kJ DeltaE = -100 Wh
d. W = 44 kPa-m3 Q = -84 kPa-m3 DelatE = 40 kN-m
In: Mechanical Engineering
Make the Bond graph model of Hydraulic ABS system in 20SIM software and simulate it
In: Mechanical Engineering
1. Selected Aircraft: Embraer ERJ 145 XR
2. Maximum Takeoff Weight (MTOW) [lbs]: 53,131 lbs
3. Engine Type and Rated Thrust [lbs]: Rolls-Royce AE3007 A1E and 7,800
4. Total Available Thrust (sum of all engines for multiengine aircraft) [lbs]: 15,600 pounds
5. Take-off distance at MTOW [ft]: 7,448 ft
Utilizing the above researched information, derive and present (in an instructional way) approaches and solutions to the following problems:
1.) If your selected aircraft's takeoff speed at MTOW was assumed to be 150 kts (i.e., the speed that is reached in the above researched takeoff distance), explain how to find and determine:
a. The total acceleration a [ft/s2] during takeoff roll
b. The sum of retarding forces FR [lb] (drag + friction) that was present during takeoff
c. The time t [s] it took for this takeoff
2.) Given the researched knowledge about the aircraft's thrust, explain for a specific airspeed example how to determine the power P [HP].
3.) For a specific example related to your researched aircraft data, explain how to determine potential EPot[ft-lb], kinetic EKin [ft-lb], and total energy ETot [ft-lb].
4.) For a specific example, explain how the minimum required climb angle AOC [deg] to clear an obstacle can be calculated from knowledge about the obstacle's height and its distance from the point of takeoff.
In: Mechanical Engineering
Derive velocity distribution, maximum velocity, average velocity, and force in z-direction for the following flow conditions, and state your assumptions
Flow of Newtonian fluid in the form of film over flat plate due
to gravity, if kept vertical.
Flow of Newtonian fluid in the form of film over flat plate due to
pressure force, if kept horizontal
Flow of non-Newtonian fluid in the form of film over flat plate due
to gravity, if kept vertical.
Flow of non-Newtonian fluid in the form of film over flat plate due
to pressure force, if kept horizontal
Flow of Newtonian fluid between two parallel flat plate due to
gravity, if kept vertical; Plate are fixed
Flow of Newtonian fluid between two parallel flat plate due to
pressure and gravity, both Plates are fixed.
Flow of Newtonian fluid between two parallel flat plate due to
pressure and gravity, if kept vertical; one Plate is fixed, the
other is moving downwards at constant velocity, Vo.
Flow of Newtonian fluid between two parallel flat plate due to
pressure and gravity, if kept vertical; one Plate is fixed, the
other is moving upwards at constant velocity, Vo.
In: Mechanical Engineering
use experimental equilibrium data and antoine equation to draw the equilibrium curve, and compare the results, what is antoine's equation and how do I use it
In: Mechanical Engineering