Composting can be used to treat various organic wastes such as grass clippings, leaves, paper, animal manure, and the organic fraction of municipal solid waste. These wastes are converted by microbial degradation to a stabilized compost. The biochemical con-version process generates heat and consideration of this generated heat is critical in the design of composting systems. Compost managers strive to keep the compost below about 65C because hotter temperatures cause the beneficial microbes to die off. If the pile gets too hot, turning or aerating will help to dissipate the heat. Treat a compost pile on the ground as one-dimensional system of height 2 m in the vertical direction. The top of the pile has wind (at temperature 40C) blowing on it, leading to a heat transfer coefficient of 50 W/m2 K. The bottom of the pile can be approximated at the ground temperature of 20C. Consider only conductive heat transfer inside the pile and neglect any convection inside this porous pile. The volumetric bio-chemical heat generation is 7 W/m3 . The thermal conductivity of the compost material is 0.1 W/mK. 1) Setup the appropriate governing equation and boundary conditions. 2) Solve for temperature as a function of height from the ground. 3) Calculate the maximum temperature in the pile. 4) Calculate the top surface temperature of the pile. Ans: 2)T=-35 x2 + 80.06x + 20; 3) x=1.14 m; T=65.8C; 4) 40.1 C