Problem 2: Plot the LST (y?axis) corresponding to 10:00 AM versus months (x?axis) (consider the 21st day of each month as the representative of each month) for Panama City Bay, Florida.
In: Mechanical Engineering
What is the best way to reduce the average grain size in a metal speciman.
In: Mechanical Engineering
A thick steel slab (ρ= 7800 kg/m3, c= 480 J/kg·K, k=
50 W/m·K) is initially at 300°C and is cooled by water jets
impinging on one of its surfaces. The temperature of the water is
25°C, and the jets maintain an extremely large, approximately
uniform convection coefficient at the surface. Assuming that the
surface is maintained at the temperature of the water throughout
the cooling, how long will it take for the temperature to reach
50°C at a distance of 28 mm from the surface?
In: Mechanical Engineering
1- The interdependence between materials and their __________
must also be recognized.
a.
environment
b. processing
c. structure d. properties
2-The design process primarily consists of design, prototype,
and __________ stages.
a. production
b. selection
c. quality d. structure
3- Approaches to material selection goes through a sequence of
activities of design, material selection, process selection,
manufacture, evaluation, and _________.
a. production
b. marketing
c. feedback d. none of
the above
4- List three geometric considerations to consider for the needs
of the product.
5- List three mechanical properties to consider for the needs of
the product.
6- List three physical properties to consider for the needs of
the product.
Chapter 11: Fundamentals of Casting
1- A primary objective of materials processing is the production
of a desired shape in the __________ quantity.
a. maximum b.
minimum c.
multiple d. none of the above
2- The six basic steps in most casting processes include using a
mold cavity, melting process, pouring technique, solidification
process, mold removal. List the sixth step.
Sixth step is:
3- One of the first features that must be considered by a
designer of castings is the location and ___________ of the parting
plane.
a.
orientation
b. dimensional
accuracy c.
design d. quality
4- __________ is the term used to describe he taper on a pattern or casting that permits it be withdrawn from the mold.
Riser b.
Gate c.
Draft d. none of the above
In: Mechanical Engineering
1- The interdependence between materials and their __________
must also be recognized.
a.
environment
b. processing
c. structure d. properties
2-The design process primarily consists of design, prototype,
and __________ stages.
a. production
b. selection
c. quality d. structure
3- Approaches to material selection goes through a sequence of
activities of design, material selection, process selection,
manufacture, evaluation, and _________.
a. production
b. marketing
c. feedback d. none of
the above
4- List three geometric considerations to consider for the needs
of the product.
5- List three mechanical properties to consider for the needs of
the product.
6- List three physical properties to consider for the needs of
the product.
Chapter 11: Fundamentals of Casting
1- A primary objective of materials processing is the production
of a desired shape in the __________ quantity.
a. maximum b.
minimum c.
multiple d. none of the above
2- The six basic steps in most casting processes include using a
mold cavity, melting process, pouring technique, solidification
process, mold removal. List the sixth step.
Sixth step is:
3- One of the first features that must be considered by a
designer of castings is the location and ___________ of the parting
plane.
a.
orientation
b. dimensional
accuracy c.
design d. quality
4- __________ is the term used to describe he taper on a pattern or casting that permits it be withdrawn from the mold.
Riser b.
Gate c.
Draft d. none of the above
In: Mechanical Engineering
Complete the following program so that C = A*B where A and B are the matrices defined below.
N=4;
M=3;
A=rand(M,N);
B=rand(N,M);
C = ?
for m = 1: M
for n = 1 : ?
for p = 1 : ?
C (m,n) = ?
end
end
end
You may upload a script
In: Mechanical Engineering
What are some of the common decision-making errors that teams and groups encounter?
In: Mechanical Engineering
An insulated pump receives liquid engine oil (density ρ = 55 lbm/ft3 , specific heat c = 0.442 Btu/lbm-R) at 75 oF and 15 psia, and exhausts the oil at 3000 psia and 140 oF. The mass flow rate of the oil is 1.2 lbm/s. Determine the power required by the pump.
In: Mechanical Engineering
step by step solution on how to create Index Slide in solidworks
In: Mechanical Engineering
The air in a room has a pressure of 1 atm, a dry-bulb temperature of 24°C, and a wetbulb temperature of 17°C. Using the psychrometric chart, determine
(a) The specific humidity,
(b) The enthalpy, in kJ/kg dry air,
(c) The relative humidity,
(d) The dew-point temperature,
and (e) The specific volume of the air, in m3/kg dry air.
In: Mechanical Engineering
Air enters a steady-flow turbine. The conditions of the air entering and leaving the
turbine are as follows: inlet, 300 kPa and 52°C; exit, 100 kPa and 12°C. The mass
flow rate is 10 kg/s. Heat transfer from the turbine to the surroundings and the
kinetic and potential energy effects are negligible. Calculate the power developed
by the turbine. Determine whether the process in the turbine is reversible. If not,
determine the isentropic efficiency of the turbine.
In: Mechanical Engineering
In large steam power plants, the feedwater is frequently heated in closed feedwater heaters (basically heat exchangers) by steam extracted from the turbine at some stage. Steam enters the feedwater heater at 1.5 MPa and 250℃ and leaves as saturated liquid at the same pressure. Feed water enters the heater at 2.5 MPa and 60℃ and leaves at 10℃ below the exit temperature of the steam. Neglecting any heat losses from the outer surfaces of the heater, determine (a) the ratio of the mass flow rates of the extracted steam and the feedwater heater and (b) the total entropy change for this process per unit mass of the feedwater.
In: Mechanical Engineering
Joe Bruin has a big lawn in front of his house that is 30 meters wide and 20 meters long. Josephine makes him go out and mow the grass every weekend, so several years ago, he bought a fancy John Deere riding mower , which he loves to ride around his yard. The mower has a gasoline engine that is rated at 20 horsepower. To mow his lawn each week, Joe needs to use the mower for about 30 minutes, and the average power used by the mower during this period is 5 horsepower. Joe has a very healthy lawn that generates a lot of lawn clippings, and after doing the EPSS 101 biofuels lab, Joe gets the idea that 3 if he converted his mower to run on biofuelds instead of gasoline, then maybe he could use biofuels generated from his lawn clippings to power his mower
a. Calculate the weekly fuel energy requirements for Joe’s riding mower. (Hint. Don’t forget to include the efficiency of the mower’s internal combustion engine)
b. Calculate the chemical energy content of the clippings produced by Joe’s lawn each week, assume solar insolation is 5.62 kWH per square meter per day (Hint. Start with the amount of sunlight the lawn absorbs each week and then use the photosynthetic efficiency of corn to calculate the chemical energy content of the grass that grows each week)
c. Use your answer from Part b to calculate the mass of grass clippings produced by Joe’s lawn each week. Given that the density of grass clippings is 667 pounds per cubic yard, how many 50-gallon trash cans would be required to hold the clippings? (Hint: Convert the energy content you calculated for Part b to dry biomass content, and then assume that the grass clippings are 80% water)
d. Joe’s first idea is to use solar power to dry the grass clippings. Then, he would mod his riding mower to install a Stirling engine in place of the gasoline engine, and then power the engine by burning the grass clippings. Compare the fuel energy that could be provided by burning the grass clippings in this manner each week to the energy needs of Joe’s riding mower. Independent of the significant air pollution that would be generated by burning the clippings, would this scheme work? Could the clippings power Joe’s mower? Would there be any energy left over for other purposes?
e. Josephine works in a biology lab at UCLA and they have recently come up with a magic strain of bacteria that converts cellulose (the dominant organic component of grass clippings) into glucose. To create ethanol fuel, Joe and Josephine put the wet grass clippings into barrels, and then add an equal mass of water, plus a cup of the magic bacteria, and then they let it sit for two weeks while the cellulose is converted to glucose. Then, Joe takes the resulting glucose solution and adds yeast to ferment the solution to produce a 15% ethanol solution, which takes an additional week. Then, every week, he burns additional grass clippings in a large still to distill the 15% ethanol solution to create a 95% ethanol solution. The resulting distillate is clean-burning fuel, which Joe uses to power his riding mower, which he has, of course, modified to run on ethanol. Ignoring the fact that the magic strain of bacteria doesn’t really exist, will this scheme work? Would the clippings provide enough ethanol to power Joe’s mower? Would there be any additional ethanol left over for other purposes, like powering Joe’s car, or to create alcoholic beverages to 4 drink when Joe’s friends come over to watch UCLA football games on Saturday afternoons?
f. If Joe could find a way to use biofuels to power his mower, would this whole operation be sustainable? Discuss the needs of Joe’s lawn for water and nutrients. Discuss the demands on Joe’s time. Do you think Joe would have enough time to run his home biofuel operation and also have time to invite his friends over to watch football games on weekends?
In: Mechanical Engineering
§Take any two sectors (cement/ automobiles/ oil/ bottled drinking water, garments/ furniture/ refrigerators, etc) and draw their distribution/supply networks.
§ Comment on their supply chain uncertainty
§ Identify 4 or more supply chain metrics of each sector’s supply chain.
Draw/Paste supply chain network of sector-1
Draw/Paste supply chain network of sector-2
|
Attribute |
Sector-1 |
Sector-2 |
|
Quantity of product needed in each lot |
||
|
Response time that customers are willing to tolerate |
||
|
Variety of products needed |
||
|
Service level required |
||
|
Desired rate of innovation in the product |
Supply Chain metrics Sector1 and 2
In: Mechanical Engineering
1- Create a life cycle inventory flow chart analysis for the steel. The document should have the following components including important data (amounts, percentages, etc.):
- material flows
- e*nergy use
- water use
- waste flows
The flow chart should besimilar to what we have in this link:
https://www.dropbox.com/s/6ndzh1hotdsewbe/life%20cycle%20inventory%20flow%20_1.pdf?dl=0
(please in print type)
In: Mechanical Engineering