Fundamentals of Heat and Mass Transfer – Problem 1.18

A spherical interplanetary probe of 0.5-m diameter contains electronics that dissipate 150 W. If the probe surface has an emissivity of 0.8 and it does not receive radiation from other surfaces, such as the sun, what is the surface temperature of the probe? How useful was this post? Click on a star to rate it!…

A glass window of width W= 1 m and height H = 2 m is 5 mm thick and has a thermal conductivity of kg 1.4 W/m·K. If the inner and outer surface temperatures of the glass are 15°C and -20°C, respectively, on a cold winter day, what is the rate of heat loss through…

An array of 10 silicon chips, each of length L=10 mm on a side, is insulated on one surface and cooled on the opposite surface by atmospheric air in parallel flow with T∞​=24°C and u∞​=40m/s. When in use, the same electrical power is dissipated in each chip, maintaining a uniform heat flux over the entire cooled surface….

The temperature distribution across a wall 0.3 m thick at a certain instant of time is T(x) = a + bx + cx2, where T is in degrees Celsius and x is in meters, a = 200 °C, b = -200 °C /m, and c = 30 °C /m2, The wall has a thermal conductivity…

Chips of width L = 15 mm on a side are mounted to a substrate that is installed in an enclosure whose walls and air are maintained at a temperature of Tsur =T=25C. The chips have an emissivity of ε = 0.60 and a max allowable temperature of Ts = 85 C. (a) If heat…

Uniform internal heat generation at  q˙= 5 × 107 W/m3 is occurring in a cylindrical nuclear reactor fuel rod of 50-mm diameter, and under steady-state conditions the temperature distribution is of the form T(r)=a+br2, where T is in degrees Celsius and r is in meters, while a= 800 °C and b= -4.167 × 105 °C/m2. The fuel rod properties are…