In: Mechanical Engineering
Why with decreasing grain size there is decrease in impact transition temperature?
In: Mechanical Engineering
Why does diesel engine initiate 2 stage fuel injection?
What is the reason for that?
In: Mechanical Engineering
Describe the design experiments method for product and process optimization
In: Mechanical Engineering
What are the general principles of DFA? What are the steps to minimize the number of parts for an assembly?
In: Mechanical Engineering
where do atheism and christianity agree and disagree on views of the origin of the universe?
In: Mechanical Engineering
Describe 2 alternative processing approach of tool steels that enables fine and homogenous primary carbide distributions.
In: Mechanical Engineering
1. Identify and describe the four domains of Axiomatic Design
2. Why would we use Axiomatic Design or Quality Function Deployment in the design of a process and simulation model?
3. Why do we flowchart processes prior to simulation?
In: Mechanical Engineering
Explain the meaning of the following terms with respect to professional engineering practice :
a) Lump sum contract
b) Confidential disclosure
c) ACCC
d) Continuing professional development
e) Incident reports
f) Risk assessment
g) Breach of contract
h) Common law
i) Preliminary negotiations
j) Patent
In: Mechanical Engineering
Air is supplied to a convergent–divergent nozzle from a
reservoir where the pressure is 100 kPa. The air is then
discharged
through a short pipe into another reservoir where the
pressure
can be varied. The cross-sectional area of the pipe is twice
the
area of the throat of the nozzle. Friction and heat transfer may
be
neglected throughout the flow. If the discharge pipe has
constant
cross-sectional area, determine the range of static pressure in
the
pipe for which a normal shock will stand in the divergent
section
of the nozzle. If the discharge pipe tapers so that its
cross-sectional
area is reduced by 25%, show that a normal shock cannot be
drawn
to the end of the divergent section of the nozzle. Find the
maximum
strength of shock (as expressed by the upstream Mach number)
that
can be formed.
In: Mechanical Engineering
With a flowchart showing the overall activities in the production of a part or component, show the stage where the material of the part or component is determined.
In: Mechanical Engineering
state the three fan laws for variation in speed as well as three laws for variation in density
In: Mechanical Engineering
In: Mechanical Engineering
A rigid, sealed container of R134a initially at -30°C and 40% quality is placed inside a room so that it heats up at 5°C/hr. If there is 3 kg of R134a in the container, determine:
a) The volume of the container
answer must be 0.2723 m3
b) The specific volume of the vapour when the R134a finishes converting into a gas
answer must be 0.09075 m3/kg
c) The pressure when all the R134a has finished converting into a gas
answer must be 222.8 kPa
d) The energy required to turn all the R134a into a gas
answer must be 399.6 kJ
e) How long it will take for all the R134a to become a gas
answer must be 4.52 hrs
In: Mechanical Engineering
A Diesel engine with a compression ratio of 16 has a cutoff ratio of 1.5. The state before polytropic compression (exponent 1.3) is 1700 cm3 , 96 kPa and 22°C and there is isentropic expansion.
(a) Sketch the P-v diagram for this cycle.
(b) Calculate the heat transfer in and heat transfer out.
answer must be Qin = 657 J or 724 J or 866 J, Qout = 291 J or 296 J or
(c) Determine the thermal efficiency.
answer must be 56% or 59.1% or 64.1%
(d) Calculate the mean effective pressure
answer must be 230 kPa or 268 kPa
In: Mechanical Engineering