Water at 50 °F is being transported from one open reservoir to another open reservoir using a concrete pipe. The two reservoirs are 1.5 miles apart with a difference in surface elevations of 25 ft. Determine the minimum pipe diameter needed to carry 10 ft3 /s of water.
In: Mechanical Engineering
(Chapter 15)
Q: Please give an example of creep.
In: Mechanical Engineering
3.0 kg of air initially occupying a volume of 0.01 m3 at a pressure of 95.0 bar expands in a piston-cylinder assembly isothermally and without irreversibilities until the volume is 0.05 m3. Using the Redlich-Kwong equation of state, determine the
1. temperature during the process, in K
2. final pressure, in bar
In: Mechanical Engineering
Materials are subject to changes from temperature. We know there are several states of matter: solid, liquid, gas, and plasma. However, within a solid-state, materials have their properties affected, in particular brittleness. The Liberty ships of the Second World War were often breaking from cold weather.
These failures highlighted a material fracture problem.
What causes these failures, what materials are affected, and are there any that are not? How is brittleness calculated and measured (types of measurement) and what does this means for aircraft material selection and design considerations? You may include the influence of this problem from a maintenance perspective.
Your report of a minimum of 2,000 words is due for this assignment.
In: Mechanical Engineering
A spherical motile bacteria with a radius of 1.0 microns and a density approximately equal to water is swimming in water (temperature 20 C) at a speed of 8.0 microns per second. The bacteria suddenly stops swimming. Since the Reynolds number for a swimming bacteria is small, it should experience Stokes drag (F?D? = 6????Rv).
(a) How long (in seconds) does it take the bacteria to come to a “complete” stop? We’ll define a “complete” stop to be when the speed has dropped to 25.0 nanometers per second.
(b) How far (in meters) does the bacteria coast in this time?
In: Mechanical Engineering
This is problem 6-19 from El-Wakil’s Powerplant Technology book -- a 35,000 lbm/h double-effect evaporator receives motive steam at 40 psia and 300°F. Pretreated raw water enters at 60°F. The pressure in the second effect is 5 psia. Calculate, for equal heat heads, (a) the amount of motive steam required, in pound mass per hour, and (b) the surface areas for each evaporator, in square feet.
In: Mechanical Engineering
A vestibule type rotating door for a large business has three panels, each 6 feet wide and 8 feet high has 400 people passing through every hour. The panels are fitted with an average of 1/64 inch crack all the way around and the expected maximum pressure differntial between the inside and the outside is 0.288 WG. Estimate the infiltration of exfiltration.
In: Mechanical Engineering
(show work)
2 If you deposit $1,000 now and are promised payments of $500 three years from now and $1,500 five years from now, the equation that will yield the correct rate of return is:
A) -1000 = 500(P/F,i,3) + 1500(P/F,i,5)
B) 0 = 1000 + 500(P/F,i,3) + 1500(P/F,i,5)
C) 1000 = -500(P/F,i,3) - 1500(P/F,i,5)
D) 0 = -1000 + 500(P/F,i,3) + 1500(P/F,i,5)
3 For the equation: 5,000 = 1,000(P/F,i,1) - 2,000(P/F,i,2) + 7,000(P/F,i,7) + 7,000(P/F,i,9), the number of possible rate of return values is:
A) 1
B) 2
C) 3
D) 4
4there is more than one sign change in the net cash flow of a rate of return equation, the possible rate of return values will fall in the range of:
A) minus infinity to plus infinity
B) minus 100% to plus infinity
C) minus 100% to plus 100%
D) minus infinity to plus 100%
5 When multiple rate of return values are possible for a rate of return equation, one way to come up with a single value which satisfies the equation is:
A) Solve for the internal rate of return
B) Use the project net investment procedure
C) Eliminate all rate of return values above 100%
D) Eliminate all rate of return values below 0%
In: Mechanical Engineering
1. Describe the purpose of design guideline of VDI-2206 and VDI-2221.
2.Describe how VDI-2221 and 2206 can be implmented concurrently
3. Describe importance of developing a function block diagram in context of systematic design
In: Mechanical Engineering
Solve the following equations using the Newton-Raphason method. ( using matlab)
x^2+x*y^2 = 9
?3x^2 * y - y^3 = 4
?initial estimation of (x,y) = (1.2, 2.5)
?please help.. using matlab and matlab code
In: Mechanical Engineering
An 8 in. diameter grinding wheel, 1 in. wide, is used in a surface grinding operation performed on a flat piece of low carbon steel. The wheel is rotating with a surface speed of 5,000 fpm, depth of cut of 0.002 in./pass and cross feed (w) of 0.15 in. The reciprocating speed of the workpiece is 20 ft/min., and the operation is performed dry. Letting C = 300 per in2 and the ratio of chip width to average undeformed chip thickness equal to 20, estimate the undeformed chip length. Estimate the undeformed chip thickness. Calculate the required grinding power in lb*in/min. What is the amount of cutting force required for this operation?
In: Mechanical Engineering
Methane is burned with air and the exhaust products are measured (on a dry, volumetric basis) to be 4.8% CO2, 0.12% CO, 12.25% O2, and balance N2. Determine (a) the air-tofuel ratio (mass based) (5 points), (b) equivalence ratio (5 points) (c) the percent theoretical air (%) (5 points), (d) the percent excess air (%) (5 points), and (e) exhaust dew point (°C) if the exhaust is at 1 atm (5 points). (25 points)
In: Mechanical Engineering
Methane is burned with air and the exhaust products are measured (on a dry, volumetric basis) to be 4.8% CO2, 0.12% CO, 12.25% O2, and balance N2. Determine (a) the air-tofuel ratio (mass based) (5 points), (b) equivalence ratio (5 points) (c) the percent theoretical air (%) (5 points), (d) the percent excess air (%) (5 points), and (e) exhaust dew point (°C) if the exhaust is at 1 atm (5 points). (25 points)
In: Mechanical Engineering
What are main differences between the Finite Difference Method and Finite Elements Method?
How are the boundary and interior values of the finite element solution obtained?
In: Mechanical Engineering
In: Mechanical Engineering