A 70% Cu–30% Zn brass wire is cold-drawn 15 percent to a diameter of 4.53 mm. The wire is then further cold-drawn to a diameter of 3.98 mm. (a) Calculate the total percent cold work that the wire undergoes. (b) Estimate the wire’s tensile and yield strengths and elongation from Fig. 6.44.

Assume that you are appointed by a university as the technical manager of the University's Formula-SAE-A Race Car project and you are required to:

a) Identify the relationships between operational objectives and functional requirements for the case of a new Formula-SAE-A Race Car (F-SAE-A) in 2018. Cite three operational objectives and the functional requirements that are needed to realise these objectives via using qualitative measures only; and

b) What is meant by “MOE”? For the effectiveness analysis of the F-SAE-A, list what you think would be the 10 most important characteristics that should be exercised and measured in the analysis. For one of the MOE of the F-SAE-A, describe an operational scenario for obtaining a measure of its effectiveness.

The 12 cylinder 2 stroke cycle compression ignition engine of an oil tanker is operating at 150 rpm The brake mean effective pressure of the engine is 400 kPa and the excess air coefficient is 2. The crankshaft of the engine is directly coupled to a propeller and a torque of 1500 kN-m is applied. The engine operates on light fuel oil which can be approximated as C12H26. If the brake specific fuel consumption is 200 g/hp-h what is the volumetric efficiency of the engine ?

Boxes use to ship the components, must have square bases in order or attached square labels to each end. The labels may have standard hazard warnings or handling information. The labels, however, can be magnified or reduced in size, but they must remain square, presently the boxes a base of 10cm square. To pack enough components into a box, the boxes have a capacity of 4000 cm³. The boxes are made of a special fibre-glass reinforced tough plastic to protect the components and the box manufacturer charges £2.50 for an area of 500 cm².

As a cost cutting exercise calculate a box with a square base and a capacity of 4000 cm³ which has the minimum possible area. If 10,000 boxes are use per year by the component manufacturer, how much money will be saved in a year by using the new boxes with the minimum area?

Answer = £10,000

Steam is contained in a 4-liter volume at a pressure of 1.5 MPa and a temperature of 200°C. If the pressure is held constant by expanding the volume while 40 kJ of heat is added, find the final temperature. use enthalpy.

Describe How hot wire anemometer is calibrated?

a gas turbine power plant operating on brayton cycle with a fuel compressor isentropic efficiency of 80 and turbine isentropic efficiency of 85 percent and it has a pressure ratio of rp. The gas temperature is 300K at a compressor inlet and 1300K at the turbine inlet. Heat is received from a source of 1700K. Utilizing the air-standard assumption (Hot Assumption) and for pressure ratio rp which varies from 3 to 10, determine:

a) The gas temperature at the exits of the compressor and the turbine.

b) the back work ratio

c) the thermal efficiency

d) the second law efficiency

e) exergy destruction for each component

plot your results as functions of gas cycle pressure ratio, and discuss the results.

Please solve this using EES software

Considering the three classes of response of materials to changes in temperature, explain why it is a sudden change rather than an accelerating or gradual change that is important for the operation of a repeatable thermal cutout switch.

(a) Dry saturated steam at a temperature of 180ºC is to be produced in a fire tube boiler from the cooling of 50 000 kg h–1 of flue gases from a pressurised combustion process. The gases enter the tubes of the boiler at 1600ºC and leave at 200ºC. The feed water is externally preheated to 180ºC before entering the boiler. The mean specific heat capacity of the flue gases is 1.15 kJ kg–1 K–1. The latent heat of vaporisation of the water at 180ºC is 2015 kJ kg–1. Feed water temperature = 180ºC. Determine the amount of steam produced per hour, if the total heat loss is 10% of the heat available for steam raising.

(b) The overall heat transfer coefficient based on the outside area of the tubes is given as 54 W m–2 K–1. Determine the area of heat transfer required to perform this duty.

(c) The tubes within the boiler are to be 25 mm inside diameter with a wall thickness of 3 mm. The average flue gas velocity through the tubes to maintain the overall heat transfer coefficient value and to minimise pressure losses is to be more than 22 m s–1 and less than 28 m s–1. Assuming that the average density of the flue gases is 1.108 kg m–3, calculate:

(i) the minimum and maximum number of tubes in each pass

(ii) the overall length of tubes at each of these numbers of tubes

(iii) the minimum number of tube passes in each case, if the length of a boiler tube is to be less than 5 metres.

2. Write a program which reads in the text file generated in part one and writes out the same data as a comma-separated values (CSV) file for further processing.

The file should have a header line which identifies which column contains which values and should look something like this:
Time, Potentiometer, Temperature, Light, Switch0, Switch1, Switch2, Switch3
That header line should be followed by detail lines containing the measurements and should look something like this (matching the above Arduino output):
0,1,1,1,1,0.50,0.14,0.90 40,1,1,1,1,0.65,0.20,0.89

Store the data in an appropriate struct.

Small high-swirl direct-injection CI engines have fuel conversion efficiencies which are about 10 percent higher than values typical of equivalent indirect-injection engines. (ID1 engines are used because they achieve higher bmep.) What combustion-system-related differences contribute to this higher efficiency?

You are required to develop a computer code that that can solve systems of ODE. The code should request the user to choose one of the following methods for solving the system:

? Euler

? 4th Order Runge Kutta  

% Consider the following system of equations:
% -2a +5b + c + 3d + 4e - f = 0
% 2a - b - 5c - 2d + 6e + 4f = 1
% -a + 6b - 4c - 5d + 3e - f = -6
% 4a + 3b - 6c - 5d - 2e - 2f = 10
% -3a + 6b + 4c + 2d - 6e + 4f = -6
% 2a + 4b + 4c + 4d + 5e - 4f = -2

% a)
% Define a symbolic variable for each of the equation and use symbolic
% capability to solve for each unknown. Convert your results to doubles.

% Answer

% b)
% Compare the amount of time it takes to solve the system of equations
% using left division and symbolic math by using the tic and toc function.

% Answer

Explain how the use of glass walls gives rise to heating in a greenhouse. Be brief.