4. Explain why the energy efficiency in the case of ideal quenching is lower than energy efficiency in the regime of super-ideal quenching?
In: Mechanical Engineering
In: Mechanical Engineering
A composite of Al2O3 particles in an epoxy matrix contains 10 wt.% Al2O3. What are the upper and lower bounds on the elastic modulus of the composite? Data: ρAl2O3 = 3.95 g/cm3 , EAl2O3 = 300 GPa, ρepoxy = 2.0 g/cm3 , and Eepoxy = 500 MPa.
In: Mechanical Engineering
A stock steel spur pinion has a diametral pitch of pd=8 teeth/in, a 1.5 in. face, 26 full-depth teeth, and a pressure angle of Φ = 20°. If the pinion is driven against a 55-tooth steel gear at 1200 RPM by a 7 hp electric motor, determine the bending stresses and surface stresses in the pinion.
In: Mechanical Engineering
how could mechanical engineering improve plastic recycle?
In: Mechanical Engineering
A short and hollow cylindrical bar, having an outer diameter of
4.00 in and an inner diameter of 7 in, is
subjected to two simultaneous loads - an axial compressive force of
75,100 lb. and a torsional moment of
20,100 lb • in.
You are required to create two-dimensional (2D) and
three-dimensional (3D) stress elements for two stress
states on the outer and inner surfaces of the bar to in-plane and
out-of-plane stresses, respectively and then
draw the 2D and 3D Mohr's circles for these two cases.
In: Mechanical Engineering
In: Mechanical Engineering
Engineering report writing on autoclave (sterilizer) machine breakdown which occurs more often due to hard water/untreated water. The factors which leads to that and the solution to the problem. Recommendation and Summation to be included. Write 3 to 4 A4 pages.
In: Mechanical Engineering
A convergent–divergent nozzle with an exit area to throat area ratio of 3 is supplied with air from a reservoir in which the pressure is 350 kPa. The air from the nozzle is discharged into another large reservoir. It is found that the flow leaving the nozzle exit is directed inward at an angle of 4° to the nozzle centerline. The velocity on the nozzle exit plane is supersonic. What is the pressure in the second reservoir?
In: Mechanical Engineering
In transonic wind tunnel testing, the small area decrease caused by placing the model in the test section, i.e., by the model blockage, can cause relatively large changes in the flow in the test section. To illustrate this effect, consider a tunnel that has an empty test section Mach number of 1.08. The test section has an area of 1 m2 and the stagnation temperature of the air flowing through the test section is 25°C. If a model with a cross-sectional area of 0.005 m2 is placed in this test section,find the percentage change in test section velocity. Assume one-dimensional isentropic flow.
In: Mechanical Engineering
Air at a pressure of 350 kPa, a temperature of 80°C, and a velocity of 180 m/s enters a convergent–divergent nozzle. A normal shock occurs in the nozzle at a location where the Mach number is 2. If the air mass flow rate through the nozzle is 0.7 kg/s, and if the pressure on the nozzle exit plane is 260 kPa, find the nozzle throat area, the nozzle exit area, the temperatures upstream and downstream of the shock wave, and the change in entropy through the nozzle.
In: Mechanical Engineering
Air is supplied to a convergent–divergent nozzle from a large tank in which the pressure and temperature are kept at 700 kPa and 40°C, respectively. If the nozzle has an exit area that is 1.6 times the throat area and if a normal shock occurs in the nozzle at a section where the area is 1.2 times the throat area, find the pressure, temperature, and Mach number at the nozzle exit. Assume one-dimensional, isentropic flow.
In: Mechanical Engineering
For the project you have selected for this class, do the following: "House maintenance"
a. Collect the appropriate data to analyze (characterize) the current situation.
b. Decide which tool(s) from the course will be used in the analysis.
c. Analyze data using the tool(s) selected.
d. Determine course of action based on the analysis (improved situation).
In: Mechanical Engineering
A liquid at 300 F flows through a 3-in. steel pipe (schedule 40) covered with a ½ in. thickness of asbestos insulation. The ambient temperature is 80 F. The inside surface film coefficient is 40 Btu/hr-sq ft-F, and the outside surface film coefficient is 4.0 Btu/hr-sq ft-F. The thermal conductivities of steel and asbestos can be taken as 25 and 0.11 Btu/hr-ft-F respectively. What's the heat loss per foot length of the pipe?
In: Mechanical Engineering