Engineering, 31.10.2019 04:31, kcruz0609

Along, cylindrical, electrical heating element of diameter d= 10 mm, thermal conductivity k= 240 w/m·k, density rho= 2700 kg/m3, and specific heat cp= 900 j/kg·k is installed in a duct for which air moves in cross flow over the heater at a temperature and velocity of 27°c and 15 m/s, respectively.

(a) neglecting radiation, estimate the steady-state surface temperature when, per unit length of the heater, electrical energy is being dissipated at a rate of 1500 w/m.

(b) if the heater is activated from an initial temperature of 27°c, estimate the time required for the surface temperature to come within 10°c of its steady-state value. evaluate the properties of air at 450 k

Answers: 2

Show answers

Other questions on the subject: Engineering

Engineering, 04.07.2019 18:10, Candi9697

A-mn has a cubic structure with a0 0.8931 nm and a density of 7.47 g/cm3. b-mn has a different cubic structure, with a0 0.6326 nm and a density of 7.26 g/cm3. the atomic weight of manganese is 54.938 g/mol and the atomic radius is 0.112 nm. determine the percent volume change that would occur if a-mn transforms to b-mn.

Answers: 2

continue

Engineering, 04.07.2019 18:10, 0436500

Aturning operation is performed with following conditions: rake angle of 12°, a feed of 0.35 mm/rev, and a depth of cut of 1.1 mm. the work piece is aluminum alloy 6061 with t6 heat treatment (a16061-t6). the resultant chip thickness was measured to be 1.0 mm. estimate the cutting force, fc. use shear stress of 207 mpa and coefficient of friction on the tool face of 0.6.

Answers: 1

continue

Engineering, 04.07.2019 19:10, Destinationz

Asteam is contained in a rigid tank with a volume of 1 m3. initially, the pressure and temperature are 7 bar and 500 oc, respectively. the temperature drops due to cooling process. determine: (1) the temperature at which condensation begins in °c, (2) the fraction of the total mass that has condensed when the pressure decreased to 0.5 bar. (3) the volume in m3 occupied by saturated liquid at the final state?

Answers: 3

continue

Engineering, 04.07.2019 19:10, jennymares

Abarometer contains mercury with a density of 13600 kg/m3. atmospheric conditions are 95.8 kpa and 20 °c at 20 °c, the vapor pressure of the mercury is 0.000173 kpa. the column of mercury will rise to a height of most nearly. select one: a)- 0.38 m b)- 0.82 m c)- 0.48 m d)- 0.72 m

Answers: 1

continue

Do you know the correct answer?

Along, cylindrical, electrical heating element of diameter d= 10 mm, thermal conductivity k= 240 w/m...