2. (35 Pts) At a graduation cookout party, the host accidentally leaves a can of cooking...

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2. (35 Pts) At a graduation cookout party, the host accidentally leaves a can of cooking spray near the hot grill. Is there a risk of the party becoming more memorable than originally intended? PAM ORIGINAL Assume the outside surface of the grill is isothermal at TG = 500 K, and that it has an emissivity of &G = 0.9. You can model the side of the grill as a square of 0.5 x 0.5 m. The cooking spray can is an isothermal cylinder with diameter Dc = 65 mm and height Hc = 200 mm. The outside surface of the can has emissivity &c=0.5. The distance from the center of the can to the side of the grill is a = 80 mm. The ambient environment is at T = 300 K. a. (10 pts) Draw a radiation resistance network that includes the side of the grill, the cooking spray can, and the ambient environment. Label all resistances in the network. List any important assumptions you are making to enable this sort of enclosure analysis (e.g., gray, diffuse surfaces). b. (8 pts) Calculate all view factors needed to evaluate the space resistances in the radiation resistance network defined in part a. You can estimate the view factor from the cylinder to the side of the grill as: F2 = arctan (2) TT . Make sure to calculate the above formula in radians. A -2b- c. (9 pts) Solve for the steady state temperature of the can assuming that it is only subject to heat transfer due to radiation from the grill and the ambient environment (i.e., no convection or conduction to surroundings). Would the can likely explode in this case? d. (8 pts) Now, assume that the can is convectively cooled by the environment with heat transfer coefficient h = 10 W m2 K-. Would the can likely explode in this case? 2. (35 Pts) At a graduation cookout party, the host accidentally leaves a can of cooking spray near the hot grill. Is there a risk of the party becoming more memorable than originally intended? PAM ORIGINAL Assume the outside surface of the grill is isothermal at TG = 500 K, and that it has an emissivity of &G = 0.9. You can model the side of the grill as a square of 0.5 x 0.5 m. The cooking spray can is an isothermal cylinder with diameter Dc = 65 mm and height Hc = 200 mm. The outside surface of the can has emissivity &c=0.5. The distance from the center of the can to the side of the grill is a = 80 mm. The ambient environment is at T = 300 K. a. (10 pts) Draw a radiation resistance network that includes the side of the grill, the cooking spray can, and the ambient environment. Label all resistances in the network. List any important assumptions you are making to enable this sort of enclosure analysis (e.g., gray, diffuse surfaces). b. (8 pts) Calculate all view factors needed to evaluate the space resistances in the radiation resistance network defined in part a. You can estimate the view factor from the cylinder to the side of the grill as: F2 = arctan (2) TT . Make sure to calculate the above formula in radians. A -2b- c. (9 pts) Solve for the steady state temperature of the can assuming that it is only subject to heat transfer due to radiation from the grill and the ambient environment (i.e., no convection or conduction to surroundings). Would the can likely explode in this case? d. (8 pts) Now, assume that the can is convectively cooled by the environment with heat transfer coefficient h = 10 W m2 K-. Would the can likely explode in this case?