Tagliatela College of Engineering EAS112 – Methods of Engineering Analysis TO: EAS 112 Students March 27, 2013 FROM: Dr. Collura, EAS112 Instructor Subject: Project 2, Optimum Pipe Insulation A long pipe is to be installed to transport steam from a boiler to another part of the plant. Insulation is needed on the pipe for both safety and economic reasons. You are to develop a spreadsheet to calculate the surface temperature of the insulated pipe and to model the heat loss to the surrounding air as a function of the thickness of insulation on the outside of the pipe. Your model should allow for variation in the key parameters to explore the effect of various changes. Using data generated by your model, select the best insulation thickness to maximize the present value of net savings in comparison to an un-insulated pipe. Provide appropriate plots and data tables to support your decision and to show the financial penalty for using a different insulation thickness. Heat Loss Calculation The steam pipe is to be made from schedule 40 steel with a diameter in the range of 2 to 3.5 inches (nominal pipe size). The pipe will be encased in fiberglass insulation with an aluminum sheet cladding to protect from weather. Heat loss for this case can be modeled using a combination of convection and conduction heat transfer rate equations. Heat from the steam is transferred to the inside wall of the pipe by forced convection, then through each of three layers by conduction (pipe wall, insulation, cladding) and finally from the outside of the cladding to the surrounding air by natural convection. The governing equations are shown below to calculate heat transferred per unit length of pipe: QS = rate of heat lost by steam to inside pipe wall Q1, Q2, Q3 = rates of heat transferred through pipe wall, insulation, aluminum cladding, respectively QA=rate of heat lost to air ?? ???? ?? ?? ?? ?? ???? ?? ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? ?? A a ?? ???? A ?? ?? A ?? S s s s…