A jet propulsion engine has an air that enter the compressor at 100 kPa and 290K. The pressure ratio across the compressor is 14 and the turbine inlet temperature is 1500K. When the air leaves the turbine, it enters the nozzle and expands to 100kPa. Determine the pressure at the nozzle inlet and the velocity of the air leaving the nozzle
Important notes: Please be neat and write legibly, it’s important that I understand your writing and follow your thoughts. And write what tables you are using and solving every step with fully details and from which tables you got the numbers please solve it clearly
In: Mechanical Engineering
Write a project which study steady state conduction in series /parallel configuration such as are used in conventional residential constryuction .This includes analysis of the walls ,windows,doors and cieling .
Also calculate energy saving for it by using modern cumputer tools .
In: Mechanical Engineering
In an air standard Otto cycle, the maximum and minimum temperatures are 1400 and 15?C. The heat supplied per kilogram of air is 800 kJ. Calculate the compression ratio and the cycle efficiency. Calculate also the ratio of maximum to minimum pressures in the cycle.
ANSWERS(5.24/1; 48.5%; 30.42/1
In: Mechanical Engineering
A four-cylinder petrol engine has a swept volume of 2000 cm3, and the clearance volume in each cylinder is 60 cm3. Calculate the air standard cycle efficiency. If the introduction conditions are 1 bar and 24 ?C, and the maximum cycle temperature is 1400 ?C, calculate the mean effective pressure based on the air standard cycle.
ANSWERS(59.1%; 5.30 bar)
In: Mechanical Engineering
In a dual-combustion cycle, the maximum temperature is 2000 ?C and the maximum pressure is 70 bar. Calculate the cycle efficiency and the mean effective pressure when the pressure and temperature at the start of compression are 1 bar and 17 ?C, respectively. The compression ratio is 18/1.
ANSWERS(63.7%; 10.54 bar)
In: Mechanical Engineering
The engine of problem 10 is supplied with a mixture of gas and air in the proportion of 1 to 7 by volume. The estimated volumetric efficiency is 85 % and the Qnet,p of the gas is 38.6 MJ/m3. Calculate the brake thermal efficiency of the engine.
ANSWER (27.4 %)
In: Mechanical Engineering
In: Mechanical Engineering
In: Mechanical Engineering
The upper end of a vertical steel wire 4mm diameter and 2,5 m long is held securely. The other end is fixed central to a steel cylinder, 80 mm diameter and of density 7,8 Mg/m3, arranged with its axis vertically. Determine the length of the cylinder to give 0,6 torsional vibration per second.
In: Mechanical Engineering
Describe the Rockwell hardness test. Include information on the indenter type, loading conditions and quantities measured.
Describe how an Izod impact test of a polymer specimen is performed. What does the test measure?
In: Mechanical Engineering
estimate the microstructural properties (ferrite, pealite, bainite. martensite) from CCT tables. Estimated cooling time of 2900 seconds with vickers hardness value of 286
In: Mechanical Engineering
A 10-kg block A is released from rest 2 m above the 5-kg plate P, which can slide freely along the smooth vertical guides BC and DE. Determine the velocity of the block and plate just after impact. The coefficient of restitution between the block and the plate is e = 0.75. Also, find the maximum compression of the spring due to impact.The spring has an unstretched length of 600 mm
The spring with the 5 kg plate are stationary before impact at 450mm. The 600mm unstretch length of the spring is without the 5 kg plate.
In: Mechanical Engineering
Describe how Aluminium can corrode or degradein Aircraft Fuselage.
And methods for avoid degradation in Aircraft Fuselage.
In: Mechanical Engineering
Describe how Aluminium can corrode or degradein Aircraft Fuselage.
And methods for avoid degradation in Aircraft Fuselage.
In: Mechanical Engineering
1. Rocket motor cases may be fabricated as thin walled tubes from:
a) Low alloy steel of proof stress 1200 MPa and GC = 24 kJ/m measured in sheet of an appropriate thickness, or
b) Maraging steel of proof stress 1800 MPa and GC = 24 kJ/m
In a particular application the design code specifies that the design stress is StressY/1.5 where Y
is the proof stress. Calculate the minimum defect size
required to give brittle fracture in service for the two materials. Comment
on your result. You may take Young’s modulus to be 200 GPa in both cases.
2)If the fracture stress of a large sheet of
maraging
steel containing a central
crack of length 40 mm is 480 MPa, calculate the fracture stress of a similar
sheet containing a crack of length 100 mm.
In: Mechanical Engineering