Answer the following questions:
1. What is PFCU functions and State the advantage and Disadvantages of PFCU?
2. What do you understand about fly by wire?
Answer the questions in paragraph form.
Copied answer will get 60%
In: Mechanical Engineering
A manufacturer wishes to choose between two ceramics for a certain application. Data for the two ceramics tested under identical conditions were as follows:
Ceramic | Mean Fracture Stress | Weibull Modulus |
A | 500 MPa | 12 |
B | 600 MPa | 8 |
The service conditions are geometrically identical to the test conditions and impose a stress of 300 MPa. By constructing Weibull graphs with S = 1/2 for mean fracture stress or any other method, decide which ceramic will be more reliable and compare the probabilities of failure at 300 MPa. At what stress would the two ceramics give equal performance?
Answer: Stress for equal performance = 349 MPa
In: Mechanical Engineering
Use the Navier-Stokes equations to show how pressure varies with x, y and z in a hydrostatic fluid.
In: Mechanical Engineering
A velocity field is described by the following equations: ?? = 10y/(x^2 +y^2) , ?? = -10x/(x^2+y^2) , and w=0 (a) Is this flow compressible or incompressible? (b) Find the pressure gradient. Assume frictionless flow in the z-axis, the density is 1.2 kg/m3 , and the z-axis is aligned with gravity. Also assume the normal and shear effects are negligible.
In: Mechanical Engineering
For the case of incompressible flow, write all 3 components of the Navier-Stokes equations and the complete form of the differential continuity equation.
In: Mechanical Engineering
8.8. Consider blood flow in a vessel (i.e., a pipe with a porous wall that is permeable to blood). The radius and length of the vessel are R and L, respectively. In general, the flow is axisymmetric, the fluid velocity has both radial and axial components that are usually determined numerically. However, there are two approximate solutions to this problem. One is to use lubrication theory to determine the relationship between the flow rate and the pressure gradient in the vessel is R<<L. The other is to estimate the axial velocity component by solving a standard problem of unidirectional flow in a pipe with an impermeable wall, but with a different kind of no-slip condition at the wall. The conventional no-slip condition is replaced by the equation: k1/2 (du/dr)= -a*u
where k is the specific hydraulic permeability of the wall, u is the axial velocity of the fluid, r is the radial coordinate, and a is a dimensionless quantity that depends on the microstructure of the porous wall. The value of a usually varies between 0.1 and 10 depending on the size of the pores in the pipe wall.
(a) Determine the axial velocity profile in the vessel using the second approach.
(b) Find the flow rate through the vessel
(c) Estimate the slip effect a on the pressure drop of the flow rate through the pipe
In: Mechanical Engineering
Water at 300kPa and 20oC is heated in a chamber by mixing it with superheated steam at 300kPa and 300oC. The cold water enters the chamber at a rate of 1.9 kg/s. Calculate the mass flow rate of the superheated steam, if the mixture leaves the chamber at 60oC.
answer is ______kg/s
If necessary, define system and energy flows shown on sketch. Complete solution shown analytically before numbers.
In: Mechanical Engineering
In: Mechanical Engineering
How are the requirements for a design project developed?
In: Mechanical Engineering
Is it possible to design products without any demand? Explain your answer with the likely consequences.
In: Mechanical Engineering
A vapor-compression heat pump with a heating capacity of 500 kJ/min is driven by a power cycle with a thermal efficiency of 30%. For the heat pump, Refrigerant 134a is compressed from saturated vapor at -10°C to the condenser pressure of 10 bar. The isentropic compressor efficiency is 80%. Liquid enters the expansion valve at 9.6 bar, 34°C. For the power cycle, 80% of the heat rejected is transferred to the heated space. (a) Determine the power input to the heat pump compressor, in kW (b) Evaluate the ratio of the total rate that heat is delivered to the heated space to the rate of heat input to the power cycle. Round answers to 3 significant digits.
In: Mechanical Engineering
One kg of Methance (CH4) is burned with 200% theoretical air. What is the air fuel ratio on a mass basis?
In: Mechanical Engineering
Consider a simple Brayton cycle using air as the working fluid with properties assumed constant and evaluated at room temperature (300 K). Conditions at the compressor inlet are T1 = 25°C and P1 = 200 kPa. The pressure ratio is 11 and maximum cycle temperature is 750°C. Answer the following (a) Compute the back?work ratio and cycle efficiency assuming both the turbine and compressor are isentropic (b) Compute the same quantities assuming only the turbine is isentropic while the compressor has an isentropic efficiency of 75% (c) Compute the same quantities assuming only the compressor is isentropic while the turbine has an isentropic efficiency of 75%
Please show all work, assume ideal gas and cold air assumptions and please write legible. Thanks
In: Mechanical Engineering
In: Mechanical Engineering
A 3-phase, 5 kVA, 208 V, four-pole, 60 Hz, Y-connected
synchronous machine has negligible stator
winding resistance and a synchronous reactance of 8
per phase at rated terminal voltage. Themachine is operated as a
generator and delivers rated kVA at 0.8 power factor lagging.
(a) Determine the excitation voltage,
(b) Find the power angle,
(c) Draw the phasor diagram,
(d) Find the stator current assuming that the field excitation
current is now increased by 20 %
(without changing the prime mover power).
In: Mechanical Engineering