Inconel refers to a class of nickel-chromium-based superalloys that are used in high-temperature applications, such as gas turbine blades. For further improvement in the performance of gas turbine engines, the outer blade surface is coated with ceramic-based thermal barrier coating (TBC). A flat Inconel plate with a thickness of 12 mm is coated with a layer of TBC with a thickness of 300 um on its surface. At the interface between the Inconel and the TBC, the thermal contact conductance is 3500 W/m2 K. The thermal conductivities of the Inconel and the TBC are 25 W/m K and 1.5 W/m-K, respectively. The plate is in a surrounding of hot combustion gasses at 1500'C, and the convection heat transfer coefficient is 750 W/m K. Determine the temperature at the mid-plane of the Inconel plate if the outer surface temperature is 1175°C. The temperature is 1'C.

two parts to a question

A semiconductor material has a conductivity of 0.0124 W/cm-K. It has the shape of a rectangular bar with cross sectional area of 1 cm2and length of 3 cm. One end is maintained at 300 °C and the other end at 100 °C. The bar carries a current of 50 A and has resistivity of 1.5x10-3ohm-cm. Assuming the longitudinal surface is insulated, calculated the midpoint temperature in the bar.

After you exercise for a while, you may notice that your skin turns red. (A) How is the blood flow in your limb changes as a response to the exercise? When your skin turns red, how has the temperature changed at the skin surface (Tskin)? (B) During exercise, does the total heat generation rate inside your body increase or decrease from that in normal conditions? (C) What is the relationship between the total heat generation rate and the total heat loss from the skin surface to the environment by convection? Neglect sweating and radiation. (D) The total heat loss from the skin surface to the environment is hA(Tskir-Tair). Based on this convection equation and results in (C), how has the skin temperature changed during exercise? Does Tskin increase or decrease from that in normal conditions? Is this consistent with that in (A)?