Mechanical Engineering Answers

A steam turbine receive a steam flow of 13kg/s and the power output is 500kw calculate

a. The chance specific enthalpy across the turbine when velocity at entrance and exist and the difference in elevation negliable

b. The chance specific enthalpy when the velocity of entrance is 60m/s, The velocity of exist is 36m/s and inlet pipe is 3m above the exhausted pipe.

The intersecting edges of a nonorthogonal parallelepiped are defined by the

position vectors TR/A=-20 T+ 30 j + Sk, TOA=8™+ 25 j+ 10k, DA = 4T - 2 j-15k

mm. Determine the volume of this object.

What are the possible causes and remedies of engine Low oil pressure?

x ^ 3 - 3x * y ^ 2 + 3x ^ 2 - 3y ^ 2

1. A piston – cylinder containing steam at 700 kPa and 250 deg C undergoes a constant pressure process until the quality is 70%. Determine per kilogram (a) change of internal energy and (b) change of enthalpy.

1 kg of air at 7 bar pressure and 90 temperature undergoes a non-

flow polytropic process. The law of expansion is p

=Constant.

The pressure falls to 1.4 bar during the process.

Calculate: (1) Final Temperature (2) Change in Internal energy (3)

Work done (4) Heat exchange. Take R=287J/kg-K and = 1.4 for air

The main ways for improving the performances of the Brayton cycle are staged compression with intercooling and reheating. Extend these methods to the main turbine engines cycles for aviation: turbojet, turbofan and turboprop and explain where each or both methods might work or not and give appropriate reasons

If for a certain BCC crystal, the (110) plane has a separation of 1.181A and wavelength of 1.540A

Find the glance angle for the 1st line of the reflection.

B. Hence find the atomic radius

The resistance of a copper wire is 1 ohm at 20 degrees C. At what temperature will it be 1.1 ohms

A perfect gas has a molar mass of 26kg/kmol and an adiabatic index of 1.26 calculate the mass rejected when unit mass of the gas is contained in a rigid vessel at 3bar and 315 degree celcius and is cooled until the pressure falls to1.5bar