Outline what you understand by the following terms in the context of climate change. Give an example in each case.
-Milankovitch cycle
-Feedback loop
-Radiative forcing
PLEASE TYPE IT ON COMPUTER
In: Mechanical Engineering
it is about plastic deformation and elastic deformation
can you explain annealed case and non-annealed case relation to
workhardening and elongation with stress- strain curve
and
the reason although area decrease, force increase , can you explain
this with slide, twinning, dislocations, heat change ?
In: Mechanical Engineering
Q. A hypothetical velocity field is given in Cartesian
Coordinates by: V? = 4z^2t i ? 4x k where i, j and k are the unit
base vectors. t is the time variable and (x, y, z) are the
Cartesian Coordinates in the ( i, j , k ) directions respectively.
The fluid density is constant and given by p = 1000kg/m^3
5(a) Give the (x, y, z) components of V? which are written
(u, v, w)respectively. Check whether the flow satisfies the
appropriate continuity equation and conclude whether this
flow is physically possible. Note that the general continuity
equation is given on the formulae sheet at the end exam
paper.
5(b) Give the general expression of the acceleration field
from
the above velocity field in the Eulerian frame of reference
and calculate the acceleration at (t, x, y, z) = (t, ?1,5,1)
and
at (t, x, y, z) = (1, ?1,5,1) .
5(c) Calculate the component of the velocity in the direction
of
the vector t = 2 i + a j, written Vt (where a is an unknown
constant) . This can be obtained from:
Vt = V??t/|t |
where the dot indicates the dot product of vectors and the
bold font indicates that we are dealing with vectors.
5(d) Check whether the pressure field p = 2x + y satisfies
the
appropriate form of the incompressible x momentum
equation which may be derived from the equation given on
the formulae sheet at end of the examination paper. You
can neglect gravity.
In: Mechanical Engineering
What are the advantages and disadvantages of the PI controller, PD controller and PID controller ?
NOTE: please write clearly or type it in a laptop or pc
ADVANCED DYNAMICS AND CONROL SYSTEMS
In: Mechanical Engineering
methane gas CH4 enters a steady flow combustion chamber at 25 oC and 1 atm and is burned with 40 percent excess air, which also enters at 25 oC and 1 atm. After combustion, the products are allowed to cool to 25 oC. Assume complete combustion, determine the heat transfer per kmol of CH4
In: Mechanical Engineering
A plane wall is a composite of three materials, A, B and C. The wall of material A has uniform heat generation q˙ of 100000 W/m3, kA = 75 W/m K, and thickness LA = 60 mm. The wall material B has no generation with kB = 150 W/m K and thickness LB = 20 mm. The wall material C has no generation with kC = 100 W/m K and thickness LC = 20 mm The inner surface of material A is well insulated, while the outer surface of material C is cooled by a water stream with T= 30 °C and h = 1000 W/m2 K.
1. Sketch the temperature distribution that exists in the composite under steady-state conditions.
2. Determine the temperature T0 , T1 inner and outer surface of material A and T2, T3 (outer surface of material B and C)
In: Mechanical Engineering
Design 4 bevel gears for a shaft driven bicycle. Make appropriate assumptions.
In: Mechanical Engineering
A gas turbine receives 10 kg/s of helium and expands it polytropically (n = 1.8) from 1100K and 600 kPa to 100 kPa. Determine the power produced, the entropy change of the helium through the gas turbine (kW/K) and the entropy change of the surroundings (kW/K).
In: Mechanical Engineering
An adiabatic tank, 0.5 m3, is initially evacuated and charged with steam at 500 kPa and 300 C. The final tank pressure is 500 kPa. Determine the final temperature and the entropy production.
In: Mechanical Engineering
A gas turbine receives 10 kg/s of helium and expands it polytropically (n = 1.8) from 1100K and 600 kPa to 100 kPa. Determine the power produced, the entropy change of the helium through the gas turbine (kW/K) and the entropy change of the surroundings (kW/K).
answer: 28,221 kW, 10.53 kW/K (Engineering thermodynamics)
In: Mechanical Engineering
in c++
Write a function that takes a C string as an input parameter and reverses the string. The function should use two pointers, front and rear. The front pointer should initially reference the first character in the string, and the rear pointer should initially reference the last character in the string. Reverse the string by swapping the characters referenced by front and rear, then increment front to point to the next character and decrement rear to point to the preceding character, and so on, until the entire string is reversed. Write a main program to test your function on various strings of both even and odd length.
In: Mechanical Engineering
in c++
Write a function that takes a C string as an input parameter and reverses the string. The function should use two pointers, front and rear. The front pointer should initially reference the first character in the string, and the rear pointer should initially reference the last character in the string. Reverse the string by swapping the characters referenced by front and rear, then increment front to point to the next character and decrement rear to point to the preceding character, and so on, until the entire string is reversed. Write a main program to test your function on various strings of both even and odd length.
In: Mechanical Engineering
In c++
Write a program that uses a DYNAMIC two-dimensional array to store the highest and lowest temperatures for each month of the year (temperature is a decimal value). The program should output the highest and lowest temperatures for the year. Your program must consist of the following functions:
a. Function getData: This function reads and stores data in the two-dimensional array.
b. Function indexHighTemp: This function returns the index of the highest high temperature in the array.
c. Function indexLowTemp: This function returns the index of the lowest low temperature in the array.
These functions must all have the appropriate parameters.
In: Mechanical Engineering
How do we use DSC and kinetics in composite improvements.
In: Mechanical Engineering
(c) A titanium hip replacement ball joint of 23.000 mm diameter was precision ground and required to be finished to a tolerance of +/- 0.002 mm The inspection procedure resulted in the parts being measured whilst still hot at 80 C after grinding. If the coefficient of linear expansion of titanium is 10 microns/metre deg C, determine 1) The linear expansion relative to the reference temperature of 20 deg C 2) The overall result of measuring parts hot on the finished size and the type of engineering fit that may result Comment on the likelihood of the +/- 0.002 mm tolerance being obtainable and should a correction factor be applied to the measurement ?
In: Mechanical Engineering