5. Sketch two views of a turning operation to show that the back
rake angle and
the side rake angle correspond to the inclination angle and the
effective rake
angle, respectively.
In: Mechanical Engineering
1) A prototype disk brake for a bicycle is to be mounted on the hub of the rear wheel, and consists of a pair of pads of area 5cm × 1cm which are pressed against opposing faces of the steel disk. The pads are aligned with their longer dimension in the tangential rotation direction, with the pad centres at a distance of 10cm from the centre of the disk. The brake is to be tested on a rotating machine to simulate the loading and wear in service. The disk rotates at a suitable constant speed, and the brakes are applied for 10 seconds every minute, with each pad applying a normal load of 1 kN.
(a) Find a suitable rotation speed (in revs. per minute, rpm) if the test is to simulate braking a bicycle travelling at a speed of 20km/hour, with a wheel diameter (including the tyre) of 70cm.
(b) When the brakes are applied, the machine registers an increase in torque of 30 Nm. Find the friction force that is being applied to each pad, and hence estimate the friction coefficient.
(c) Estimate the depth of material removed per hour of testing, if the Archard wear constant for the materials is ka = 2×10-8 MPa-1.
(d) What other factors would influence the wear rate in service?
In: Mechanical Engineering
A turning operation in the automotive industry relates to the
reduction of the
diameter of bar stock by 6 mm for about 100,000 components. For a
constant
machining cycle time, would you recommend a single-pass operation
or a
multi-pass operation, from the point of view of tool life and
surface finish?
Why?
In: Mechanical Engineering
1. Considering heat transfer issues, give two reasons to
indicate why cutting
fluid applied in the form of a mist performs better in comparison
to a flood
application.
In: Mechanical Engineering
1a. Can we delete a drawing view in autodesk inventor? How?
1b. Can we adjust the length of centerlines in the draftingmode of inventor? how?
1c. Describe the purpose and usage of the leader text command
1d. Describe the advantage of using the 3D annotations in isometric drawins views approach as a documentation tol that is avaible in autodesk inventor
In: Mechanical Engineering
What are the differences between air-standard analysis and cold air-standard analysis? What is the tradeoff in using air-standard analysis vs. using cold air-standard analysis?
In: Mechanical Engineering
Crude oil of density 970 kg.m-3 flows in a pipe of internal diameter 9 inches and circular section that exhibits a 90° bend in the horizontal plane. The flowrate of the oil is 11,000 litres per minute. Calculate the force imparted by the oil on the bend due to the change of momentum of the fluid, and draw a diagram to indicate the direction of this force.
In: Mechanical Engineering
120 kilograms of saturated water at 2.32 MPa pressure is heated to saturated vapor at same pressure. Determine heat required for the process.
In: Mechanical Engineering
Refrigerant-134a is throttled from the saturated liquid state at 700 kPa to a pressure of 160 kPa. Determine the temperature drop during this process and the final specific volume of the refrigerant.
In: Mechanical Engineering
A heavily insulated steam turbine operates steadily and is supplied with 1 kg/s steam at 2MPa, 400 deg C. If the outlet temperature is 100 deg C and the turbine has an output of 1000 kW determine the quality of the outlet steam, the rate of entropy generation and the isentropic efficiency of the turbine. (Changes in kinetic and potential energy are negligible).
In: Mechanical Engineering
A heavily insulated steam turbine operates steadily and is supplied with 1 kg/s steam at 2MPa, 400 deg C. If the outlet temperature is 100 deg C and the turbine has an output of 1000 kW determine the quality of the outlet steam, the rate of entropy generation and the isentropic efficiency of the turbine. (Changes in kinetic and potential energy are negligible).
In: Mechanical Engineering
CFD question
How does interfacial density relate to drag and saltation model?
In: Mechanical Engineering
Explain the failure criteria in 2-D stress-strain analysis.
In: Mechanical Engineering
Consider a 2-mm-diameter sphere immersed in a fluid at 300 K and 1 atm.
(a) If the fluid around the sphere is quiescent and extensive, show that the conduction limit of heat transfer from the sphere can be expressed as NuD,cond = 2. Hint: Begin with the expression for the thermal resistance of a hollow sphere, letting r2 →∞ and then expressing the result in terms of the Nusselt number.
(b) Considering free convection, at what surface temperature will the Nusselt number be twice that for the conduction limit? Consider air and water as the fluids.
(c) Considering forced convection, at what velocity will the Nusselt number be twice that for the conduction limit? Consider air and water as the fluids.
In: Mechanical Engineering
In: Mechanical Engineering