Learn more about our help with Assignments: Mechanical Engineering
Search & Filtering
Mechanical Engineering
Find Equivalent processing time (min) at 100oC and 150oC, respectively, which will determine the lethality equivalent to that obtained at 121oC. F121 = 45min and Z= 10.5oC.
Mechanical Engineering
The D121 and Z- value for a thermophilic spore in whole milk were experimentally determined as 30 s and 10.5oC respectively. Calculate D150 (min) for the spore.
Mechanical Engineering
A 600 g ball A is moving with a velocity of magnitude 6 m/s when it hit by a 1 kg ball B that has a velocity of magnitude 4 m/s. Knowing that the coefficient of restitution is 0.8 and assuming no friction, determine the velocity of each ball after impact.
Mechanical Engineering
A cylinder contains 0.03 m^3 of steam with a dryness fraction of 0.8 at a pressure of 16 bar. The steam expand during a steady reversible non-flow hyperbolic process until the volume becomes 0.24 m^3.
With information from the steam tables at 16 bar, for the initial state (state 1):
a) Calculate
i. the specific volume for the initial state
ii. the specific internal energy for the initial state
iii. the specific enthalpy energy for the initial state
iv. the mass of the steam
b) Calculate the pressure at the final state
c) Calculate the specific volume at final state
With information from the steam tables at the final pressure, for the final state (state 2)"
d) calculate
i. the dryness fraction of steam at state 2
ii. the specific internal energy for the final state
iii. the specific enthalpy for the final state
Calculate for the steady non-flow hyperbolic process:
e) the work energy transfer
f) the change in internal energy
g) the heat energy transfer
With information from the steam tables at 16 bar, for the initial state (state 1):
a) Calculate
i. the specific volume for the initial state
ii. the specific internal energy for the initial state
iii. the specific enthalpy energy for the initial state
iv. the mass of the steam
b) Calculate the pressure at the final state
c) Calculate the specific volume at final state
With information from the steam tables at the final pressure, for the final state (state 2)"
d) calculate
i. the dryness fraction of steam at state 2
ii. the specific internal energy for the final state
iii. the specific enthalpy for the final state
Calculate for the steady non-flow hyperbolic process:
e) the work energy transfer
f) the change in internal energy
g) the heat energy transfer
Mechanical Engineering
A refrigerant plant of 100 TR capacity uses R-22 as refrigerant. The condensing and evaporating pressure are 11.82 bar and 1.64 bar, respectively. The refrigerant enters the compressor at dry saturated state, whereas it leaves the condenser, subcooled by 10°C. Actual COP is 70% of its theoretical value. Find the following:
a) Theoretical and actual COP
b) Mass flow in kg/s
c) Compressor power.
Mechanical Engineering
Consider the same plate as in the previous question: a square plate of L=1L=1m side attached to a torsionnal spring of stiffness 10Nm/rad. The mass of the plate is M=1M=1Kg. Now the air flow is coming from the left at 10m/s. What is the eigenfrequency (Hz) of this oscillator
Mechanical Engineering
using the equipartition of energy concept estimate the ideal gas Cp(not Cv) in units KB for the low temperature regime where no vibrational modes are activated(if you calculate Cp=42KB, enter 42 as your answer )
Mechanical Engineering
A fluid at 0.7 bar occuping 0.09m^3 is compressed reversibly to a pressure of 3.5 bar according to the law pv^n=constant.The fluid is then heated reversibly at constant volume until the pressure is 4bar;the specific volume is then 0.5 m^3/kg.A reversible expansion according to a law pv^2=constant restore the fluid in its initial state.Sketch the cycle on ap-v diagram and calculte (i)the mass of fluid present (ii)the value of n in the first process (iii)the net work of the cycle
Mechanical Engineering
aluminium bar 600mm long with diameter 40mm,has a hole drilled in the centre of the bar ,the hole is 30mm in diameter and is 100mm long,if modulas of elasticity for aluminium is 85GN/m squared,calculate the contraction of the bar due to a compresssive laod of 180kN.
Mechanical Engineering
CONSIDER A CHIMNEY
Boiler uses 20kg of Air per kg of fuel Calculate the minimum height of chimney required to produce a draught of 30mm of water
The mean temperature of chimney gases is 290°c and that of outside is 27°c
Boiler uses 20kg of Air per kg of fuel Calculate the minimum height of chimney required to produce a draught of 30mm of water
The mean temperature of chimney gases is 290°c and that of outside is 27°c
