Mechanical engineering Archives - Page 3 of 7

Question Cagtegory: Mechanical engineering

All Questions

Filter by

Questions Per Page:

A 30 mm OD pipe is to be insulated with asbestos having a thermal conductivity of 0.1 W/mK. The convective heat transfer coefficient is 5W/m²K. What is the critical radius of insulation for this pipe?
A 30 mm OD pipe is to be insulated with asbestos having a thermal conductivity of 0.1 W/mK. The convective …
fluids

heat and mass transfer

Mech_59 Asked on 14th August 2023 in Mechanical engineering.
- 750 views
- 1 answers
- 0 votes
What is the ratio of heat flows from two walls of same area and thickness ratio 1:2 and thermal conductivity ratio 3:1 for the same temperature diiference on the two sides?
What is the ratio of heat flows from two walls of same area and thickness ratio 1:2 and thermal conductivity …
fluids

heat and mass transfer

Mech_59 Asked on 7th August 2023 in Mechanical engineering.
- 405 views
- 1 answers
- 0 votes
The temperature at the inner and outer surfaces of a 15 cm thick plane wall are measred to be 40°C and 28°C, respectively. What is the expression for steady, one-dimensional variation of temperature in the wall ?
The temperature at the inner and outer surfaces of a 15 cm thick plane wall are measured to be 40°C …
fluids

heat and mass transfer

Mech_59 Asked on 7th August 2023 in Mechanical engineering.
- 437 views
- 1 answers
- 0 votes
A composite wall having three layers of thickness 0.3m, 0.2 m and 0.1 m and with thermal conductivities 0.6, 0.4, 0.1 W/(m-K), respectively, is having surface area 1 m2.
A composite wall having three layers of thickness 0.3m, 0.2 m and 0.1 m and with thermal conductivities 0.6, 0.4, …
fluids

heat and mass transfer

Mech_59 Asked on 7th August 2023 in Mechanical engineering.
- 404 views
- 1 answers
- 0 votes
The variation of temperature in a plane wall is determined to be T(x) = 110 – 48x where x is in m and T is in °C. If the thickness of the wall is 0.75 m, what the temperature difference between the inner and outer surface of the wall?
The variation of temperature in a plane wall is determined to be T(x) = 110 – 48x where x is …
fluids

heat and mass transfer

Mech_59 Asked on 2nd August 2023 in Mechanical engineering.
- 386 views
- 1 answers
- 0 votes
A hollow sphere is made up of two materials, first with k = 70 W/m K having an I.D. of 10 cm and O.D. of 30 cm and the second with k = 15 W/m K forms the outer layer with O.D. of 40 cm. The inside and outside temperature are 300°C and 30°C, respectively.
A hollow sphere is made up of two materials, first with k = 70 W/m K having an I.D. of …
fluids

heat and mass transfer

Mech_59 Asked on 2nd August 2023 in Mechanical engineering.
- 402 views
- 1 answers
- 0 votes
A stainless steel tube (kst = 19W/mK) of 2 cm ID and 5 cm OD is insulated with 3 cm thick asbestos(ka = 0.2 W/mK). If the temperature difference between the inner most and outermost surfaces is 600°C, What is the heat transfer rate per unit length?
A stainless steel tube (kst = 19W/mK) of 2 cm ID and 5 cm OD is insulated with 3 cm …
fluids

heat and mass transfer

Mech_59 Asked on 31st July 2023 in Mechanical engineering.
- 370 views
- 1 answers
- 0 votes
A copper pipe having 35 mm OD and 30 mm ID carries liquid oxygen to the storage site of a space shutle at -182° C and 0.06 m3/min. The ambient air is at 20°C and has a dew point of 10°C.
A copper pipe having 35 mm OD and 30 mm ID carries liquid oxygen to the storage site of a …
fluids

heat and mass transfer

Mech_59 Asked on 31st July 2023 in Mechanical engineering.
- 447 views
- 1 answers
- 0 votes
A thin-walled copper tube of outside metal radius r = 0.008 m carries stream at 383 K. It is inside a room where the sourrounding air temperature is 300 K. The tube is insulated with magnesia insulation of an approximate thermal conductivity of 0.071 W/(mK).
A thin-walled copper tube of outside metal radius r = 0.008 m carries stream at 383 K. It is inside …
fluids

heat and mass transfer

Mech_59 Asked on 31st July 2023 in Mechanical engineering.
- 408 views
- 1 answers
- 0 votes
For a current carrying wire of 20mm diameter exposed to air (h = 20 W/m2K), What is the thickness of insulation (k = 0.5 W/mK) for maximum heat dissipation?
For a current carrying wire of 20mm diameter exposed to air (h = 20 W/m2K), What is the thickness of …
fluids

heat and mass transfer

Mech_59 Asked on 25th July 2023 in Mechanical engineering.
- 453 views
- 1 answers
- 0 votes

Tags

LATEST QUESTIONS

Tags