Engineering, 27.02.2020 04:51 jjcw000

A 1200-W iron is left on the iron board with its base exposed to ambient air at 26°C. The base plate of the iron has a thickness of L = 0.5 cm, base area of A = 150 cm2 , and thermal conductivity of k = 18 W/m·K. The inner surface of the base plate is subjected to uniform heat flux generated by the resistance heaters inside. The outer surface of the base plate whose emissivity is ε = 0.7, loses heat by convection to ambient air with an average heat transfer coefficient of h = 30 W/m2 ·K as well as by radiation to the surrounding surfaces at an average temperature of Tsurr = 295 K. Disregarding any heat loss through the upper part of the iron,

(a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the plate,

(b) obtain a relation for the temperature of the outer surface of the plate by solving the differential equation, and

(c) evaluate the outer surface temperature.

Answers: 3

Show answers

Another question on Engineering

Engineering, 03.07.2019 15:10

Apiston-cylinder with a volume of 0.25 m3 holds 1 kg of air (r 0.287 k/kgk) at a temperature of 100 c. heat transfer to the cylinder causes an isothermal expansion of the piston until the volume triples. how much heat is added to the piston-cylinder?

Answers: 3

Answer

Engineering, 04.07.2019 18:10

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

Answers: 1

Answer

Engineering, 04.07.2019 18:10

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.

Answers: 3

Answer

Engineering, 04.07.2019 18:10

Slip occurs via two partial dislocations because of (a) the shorter path of the partial dislocation lines; (b) the lower energy state through partial dislocations; (c) the charge balance.

Answers: 1

Answer

You know the right answer?

A 1200-W iron is left on the iron board with its base exposed to ambient air at 26°C. The base plate...

Questions