Mechanical engineering Archives

Worldtech
Investigate the principles of aerodynamics in mechanical engineering, covering topics such as fluid flow around objects, lift and drag forces, and boundary layer phenomena.
on 1st December 2024 in Mechanical engineering.
- 40
- 1
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Mech_59
Two large diffuse gray parallel plates, separated by a small distance, have surface temperature of 400 K and 300 K. If the emmissivities of the surface are 0.8 and the Stefan-Boltzmann constant is 5.67 x 10^-8 W/m3K4, What is the net radiation heat exchange rate in KW/m3 between the two plates?
- fluids
- heat and mass transfer
on 16th October 2023 in Mechanical engineering.
- 447
- 1
- 0
Mech_59
Two concentric spheres of diameters D1 = 0.5 m and D2 = 1 m are separated by an air space as shown in given figure and have surface temperatures of 400 K and 300 K respectively.
- fluids
- heat and mass transfer
on 13th October 2023 in Mechanical engineering.
- 435
- 1
- 0
Mech_59
Consider a hot, boiled egg in a spacecraft that is filled with air at atmospheric presssure and temperature at all times.
- fluids
- heat and mass transfer
on 13th October 2023 in Mechanical engineering.
- 447
- 1
- 0
Mech_59
Air at 27°C and 1 atm flows over a flat plate at velocity of 2 m/s. Assume that the plate is heated over its entire lenght to a temperature of 60°C.
- fluids
- heat and mass transfer
on 12th October 2023 in Mechanical engineering.
- 425
- 1
- 0
Mech_59
A fluid flowing over a flat plate has the following properties : dynamic viscosity = 25 x 10^-6 kg/ms, specific heat = 2.0 kJ/kgK, thermal conductivity 0.05 W/mK.
- fluids
- heat and mass transfer
on 12th October 2023 in Mechanical engineering.
- 434
- 1
- 0
Mech_59
An aluminium sphere weighning 5.5 kg and initially at a temperature of 290°C is suddenly immersed in a fluid at 15°C. The convective heat transfer coefficient is 58 W/m²K.
- fluids
- heat and mass transfer
on 29th September 2023 in Mechanical engineering.
- 815
- 1
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Mech_59
A metallic rod (k = 32 W/m°C), 10 mm in diameter and 80 mm long, with an insulated end is to be used as spine. It is expossed to sourrounding with a temperature of 80°C and a heat transfer coefficient 55 W/m²°C.
- fluids
- heat and mass transfer
on 29th September 2023 in Mechanical engineering.
- 407
- 1
- 0
Mech_59
What is the efficciency of a plate fin of length L = 1.5 cm and thickness 2 mm, (if k = 210 W/m-K, h = 285 W/m²k).
- fluids
- heat and mass transfer
on 28th September 2023 in Mechanical engineering.
- 1K
- 1
- 0
Mech_59
It is required to heat oil to about 500°C for quenching purpose. A ladder is used in the furnace. The section of ladder is (10 x 20) mm². The sourroundings are at 27°C.
- fluids
- heat and mass transfer
on 28th September 2023 in Mechanical engineering.
- 2K
- 1
- 0