Saturated water at 20 C flows inside the annular region formed by two concentric circular tubes. The OD=71 in mm, while the ID= 101 mm, The mass flow rate is 0.02 kg/s. , The outer surface is insulated, and the inner surface is kept at 71 C, . Determine the heat transfer coefficient from inner surface to water   under fully developed velocity and temperature flow conditions. Use the following constant thermo-physical properties of water, ρ = 1000kg/m3; μ = 1×10-5 kg/m-s; k = 0.027 W/m-°C; Cp = 4000 J/kg-°C

ROUND UP TO 4 DECIMAL PLACES. Draw and label the P-V & T-S diagrams.

An Ideal air standard dual-combustion cycle has a compression ratio of 15. At the start of the compression process, the air temperature and pressure are 30°C and 150kPa respectively. Heat addition takes place until the maximum cycle temperature reaches 1950°C and produces total heat of 1200 kJ/kg. Determine (a) Temperature, specific volume and Pressure at each state, (b) Net work output (kJ/kg), and (c) thermal efficiency. (d) cut off ratio. (e) mean effective pressure (kPa)

Only 50% of the irradiation on the human skin are absorbed that fall in the range of ?1=0.71 ?? to ?2=1.71 ?? .Radiation with shorter wavelengths than ?1 and longer wavelengths than ?2 are completely absorbed. Assuming the solar surface to be a black surface of temperature 5527C, calculate the fraction of solar irradiation absorbed by the human skin?

Suppose you have a 4340 steel plate in fully reversed axial loading, with an axial load varying from 15000 lbf to -15000 lbf. The plate is 1⁄4” thick, 2” high, and 5” long. A hole is in the center of the plate, and is 1/4“ in diameter. The stress concentration factor chart is in the Quiz 3 References. The fully adjusted endurance limit was found to be Se = 25 ksi.​

The fatigue strength fraction f is 0.76. The notch sensitivity is 0.95.

What is the life in cycles of this bar?

References Fully Reversed Loading Fatigue:

https://d3c33hcgiwev3.cloudfront.net/_b812cd169fbe57b00756e256731aa4a3_Quiz-3--References-Fully-Reversed-Loading-Fatigue-.pdf?Expires=1593993600&Signature=c5lXDSj-l8Sa7aUp1pCxY88L-MSbdEMoEUYl-YZMNvdU11UqQ-2vZAPYcuzbYmwZt28RMIoSf~KHf-5h6nZgUc89eqWDtLRmffjmk1wjAgll8Vgnuhza-m3ni5~IjL9utiaQrGCmoFZBEr8FzNyHi1629kpKoMAL4FHW7TRLG5g_&Key-Pair-Id=APKAJLTNE6QMUY6HBC5A

Explain the phenomena of creep and stress rapture

A fuel mixture consists of 90% octane (C₈H₁₈) and 10% ethyl alcohol (C₂H₅OH), by volume. This fuel mixture is burned with 200% theoretical dry air in a combustion chamber at atmospheric pressure.

a) Write the balanced reaction equation for complete combustion of this fuel mixture.

b) Determine the theoretical air-fuel ratio.

c) Actual air-flow rate for a fuel mixture flow rate of 5 kg/s.

d) Calculate the molar mass of the mixture product gases.

can someone explain teardown analysis and competitive benchmarking with examples, please?

A water pump has the following performance based on the tabulation below: Q, liters/min Total head, m Power in, W 100 12.0 208.5 120 10.0 204.2 140 8.5 211.3 160 7.5 227.9 180 7.0 263.8

1. Make computations each for the efficiencies at the different flowrates and total heads of the pump. Recommend at what total head should the pump be operated for maximum efficiency.

PART 1

The company would like to investigate how the actual performance of the suspension system compares to that of theory. Dynamic theory states that the equation of motion of the wheel in the vertical direction can be expressed as,

  m d 2 y d t 2 = − c d y d t − k y   or d 2 y d t 2 + c m d y d t + k m y = 0

where m is the mass of the wheel, k is the spring stiffness and c is the damping coefficient.

This is a second order differential equation, and if for example, the car hits a hole at t = 0, such that it is displaced from its equilibrium position with y = y₀, and dy/dt = 0, it will have a solution of the form,

y ( t ) = e − n t ( y 0 cos ⁡ ( p t ) + y 0 ( n p ) sin ⁡ ( p t ) )

where   p = k m − c 2 4 m 2 and n = c 2 m provided   k m > c 2 4 m 2

To analyse the actual performance of the design, the suspension system was built and tested with the following displacements of the wheel recorded during the time period of 2.6 and 3.1 seconds (this dataset is known to contain experimental error):

The design team are interested if the dataset can be characterised by expressions which are less complex than that of the above theory.

PART 2

The design team performed stress analysis on the coil spring, and it was determined that the stress at a specific point could be characterised by:

Similar calculations were performed to calculate the maximum principal stress at 420 locations along a non-linear path through the coil spring. The following frequency distribution of the calculated maximum principal stresses was produced:

The design team is interested in the significance of these frequencies and therefore need to calculate the area under the graph which displays these results.

The design team believe any further calculations of principal stresses and determining the area under the graph will be time consuming (and potentially error prone), thus would like an automated method for performing this.

Submission

Create two separate MATLAB scripts for Part 1 and Part 2:

PART 1 - Create a MATLAB script which is capable of performing the following:

• Plotting the theoretical displacement of the wheel which shows the first 8 roots when the suspension system has the following specifications:
  • mass acting on each wheel = 3.6 x 10³ kg
  • c = 1.5 x 10³ Ns/m
  • k = 1.5 x 10⁴ N/m                        
  • initial displacement = 0.3 m
• Calculating the time for the 3^rd, 6^th and 7^th occasion when the wheel passes through the equilibrium position (i.e. the root);
• Calculating the value of the coefficient of multiple determination (R 2 ) and the standard error ( σ E) when presuming the experimental dataset is characterised by a power equation (y = a x b );
• Plotting a graph of the experimental dataset of the wheel displacement (displacement vs time) with a curve calculated using regression analysis when presuming the dataset is characterised by a power equation (y = a x b);
• Calculating the displacement of the wheel at 2.8s when presuming the experimental dataset is characterised by a power equation (y = a x b ).

PART 2 – Create a MATLAB script that is capable for performing the following:

• Calculating the maximum principal stress at the specific point shown;
• Plot the frequency distribution of the calculated maximum principal stresses and fit a natural spline through the dataset;
• Calculate the area under the natural spline (between the data points given).

Two parallel thin sheets are placed 2 cm apart. The sheets are squares of sides 5 m. Temperature of both sheets are constant with one at ?! = 15 °? and the other at ?! = -120 °?.

The emissivity of surfaces can be assumed to be 1.

Determine the rate of heat transfer between the plates assuming the gap between the plates is:

a. Vacuum

b. Filled with air at atmospheric pressure (air is not moving)

c. Please state any assumptions you make in your calculations

Thermal conductivity of air at 1 atm is 0.0223 W/m · °C Thermal conductivity of superinsulation is 0.00015 W/m · °C

Illustrate various Air Cargo Scheduling Problems (ACSP) with appropriate examples taking any imaginary route/data of your choice (500-600 words).

A 3-mm-diameter and 12-m-long electric wire is tightly wrapped with a 1.5-mm-thick plastic cover whose thermal conductivity and emissivity are k 5 0.20 W/m·K and « 5 0.9. Electrical measurements indicate that a current of 10 A passes through the wire and there is a voltage drop of 7 V along the wire. If the insulated wire is exposed to calm atmospheric air at T` 5 30°C, determine the temperature at the interface of the wire and the plastic cover in steady operation. Take the surrounding surfaces to be at about the same temperature as the air. Evaluate air properties at a film temperature of 40°C and 1 atm pressure. Is this a good assumption?

Water is flowing through a pipe having the diameter 200 mm and 100 mm at sections 1 and 2 respectively. The rate of flow through the pipe is 35 liters per second. The section 1 is 6000 mm and section 2 is 4000 mm above the datum line. If the pressure at the section 1 is 0.4 N/mm², find the intensity of pressure at section 2.                                                            

a. Briefly describe (with the use of diagrams) the Brayton’s cycle and derive the formula for
the coefficient of performance for the Brayton’s cycle
b. A Bell-Coleman refrigerator operates between pressure limits of 2 bar and 14 bar. Air is drawn from the cold chamber at 100C, compressed and then it is cooled to 32OC before entering the expansion cylinder. Expansion and compression follow the law pv1.35 = constant. Calculate the theoretical C.O.Pof the system
ForairtakeƳ=1.6,CP =1.205kJ/kgK andPV1.23=C

The change of the motor moment (Mm) and the resistance moment (Md) in a 2? period machine with a conservative force field are as follows.
?? = 100? / ?, 0 ≤ ? <? (Nm)
?? = 200 - 100? / ?, ? ≤ ? <2?
?? = 50, 0 ≤ ? <2?
The average speed of the machine is 100 rad / s and the variable part of the moment of inertia is ?? = (0.003) sin (2?). If the speed unevenness is 1% and the current flywheel value is 0.4 kgm ^ 2, find the flywheel amount that should be added to the machine.