Insulating materials are frequently installed with a reflective coating to reduce the radiation heat transfer between the surface and the surroundings. An insulating material is installed on a furnace oven wall that is maintained at 200ºC. The energy cost of the fuel firing the oven is $8.25/GJ and the insulation installation must be justified by the savings in energy costs over a three-year period. Select an appropriate insulation from Table 2-1 and/or Table A-3 and determine a suitable quantity of insulation that will pay for itself over a three-year period. For this computation assume that the outer surface of the insulation radiates like a blackbody and that the heat loss can be determined from Equation (1-12). For the calculation use Table 1-2 as a guide for selecting the convection heat-transfer coefficient. Next, consider the same type of insulating material but with a reflective coating having ε = 0.1. The radiation transfer may still be calculated with Equation (1-12). Determine the quantity of the reflective insulating material required to be economical. How much higher cost per unit thickness or volume could be justified for the reflective material over that of the nonreflective? Comment on uncertainties which may exist in your analysis.