Determination of insulation thickness by means of exergy analysis in pipe insulation

Abstract Energy consumptions in buildings can be reduced considerably using insulation materials. Even in well-insulated buildings energy consumption can be reduced further by insulating transmission pipes. For this reason, the energy savings can be obtained by using proper thickness of insulation in these areas. In this study, insulation thickness has been optimized by using exergy method and life-cycle cost concept for the case of using various fuels such as coal, natural gas and fuel–oil. This analysis is based on the exergetic cost of insulation materials and fuel. As a result, combustion parameters such as excess air, stack gas temperature, and combustion chamber parameters are much more effective on optimum insulation thickness. The optimum insulation thickness decreases with the increasing of inlet temperature of fuel, and with the decreasing of excess air coefficient, temperatures of stack gases and combustion chamber. Under this effects, the optimum insulation thicknesses determine as 0.065, 0.071, 0.099 m with a rate of 68.27%, 71.54% and 77.85% in the exergetic saving for natural gas, coal and fuel–oil fuels, respectively. The optimum insulation thickness, total annual exergetic cost, exergy saving, and exergy losses depending on heat transfer increase with the increase of heating degree-days, while they decrease by increasing the temperature of outside air (reference state). In addition, the optimum insulation thickness for the exergoeconomic optimization is higher than that of energoeconomic optimization.

[1]  Zoltán Pásztory,et al.  Multi-layer heat insulation system for frame construction buildings , 2011 .

[2]  Dias Haralambopoulos,et al.  Assessing the thermal insulation of old buildings—The need for in situ spot measurements of thermal resistance and planar infrared thermography , 1998 .

[3]  Mehmet Ali Alkan,et al.  Thermo-economic analysis of pipe insulation for district heating piping systems , 2011 .

[4]  G. M. Zaki,et al.  Cooling load response for building walls comprising heat storing and thermal insulating layers , 1991 .

[5]  A. Bejan.  Fundamentals of exergy analysis, entropy generation minimization, and the generation of flow architecture , 2002 .

[6]  M. J. Moran,et al.  Thermal design and optimization , 1995 .

[7]  Mario A. Medina,et al.  Reducing Heat Transfer Across the Insulated Walls of Refrigerated Truck Trailers by the Application of Phase Change Materials , 2010 .

[8]  Y. Çengel,et al.  Thermodynamics : An Engineering Approach , 1989 .

[9]  Evangelos G. Giakoumis,et al.  Cylinder wall insulation effects on the first- and second-law balances of a turbocharged diesel engine operating under transient load conditions , 2007 .

[10]  Mehmet Kanoglu,et al.  Exergetic and thermoeconomic analyses of diesel engine powered cogeneration: Part 1 – Formulations , 2009 .

[11]  E. Bilgen,et al.  Thermo-economic optimization of hot water piping systems : A comparison study , 2006 .

[12]  Ali Bolatturk,et al.  Determination of optimum insulation thickness for building walls with respect to various fuels and climate zones in Turkey , 2006 .

[13]  Ö. Altan Dombaycı,et al.  Optimization of insulation thickness for external walls using different energy-sources , 2004 .

[14]  Wei Chen,et al.  Thermal analysis on the cooling performance of a wet porous evaporative plate for building , 2011 .

[15]  K. S. Ong.  Temperature reduction in attic and ceiling via insulation of several passive roof designs , 2011 .

[16]  Aynur Ucar,et al.  Thermoeconomic analysis method for optimization of insulation thickness for the four different climatic regions of Turkey , 2010 .

[17]  Derya Burcu Özkan,et al.  Optimization of insulation thickness for different glazing areas in buildings for various climatic regions in Turkey , 2011 .

[18]  Abdullah Yildiz,et al.  ECONOMICAL AND ENVIRONMENTAL ANALYSES OF THERMAL INSULATION THICKNESS IN BUILDINGS , 2008 .

[19]  Ramazan Köse,et al.  Thermoeconomic optimization of insulation thickness considering condensed vapor in buildings , 2006 .

[20]  H. T. Ozkahraman,et al.  The use of tuff stone cladding in buildings for energy conservation , 2006 .

[21]  Afif Hasan,et al.  Optimizing insulation thickness for buildings using life cycle cost , 1999 .

[22]  M. S Söylemez,et al.  Optimum insulation thickness for refrigeration applications , 1999 .

[23]  Ibrahim Dincer,et al.  On thermal energy storage systems and applications in buildings , 2002 .

[24]  Abdul Jabbar N. Khalifa,et al.  Effect of insulation thickness on the productivity of basin type solar stills: An experimental verification under local climate , 2009 .

[25]  Tayfun Uygunoğlu,et al.  LCC analysis for energy-saving in residential buildings with different types of construction masonry , 2011 .

[26]  Wan Ki Chow,et al.  Optimum insulation-thickness for thermal and freezing protection , 2005 .

[27]  Moncef Krarti,et al.  Optimization of Korean crop storage insulation systems , 2003 .

[28]  W. Chen,et al.  The inaccuracy of heat transfer characteristics for non-insulated and insulated spherical containers neglecting the influence of heat radiation , 2011 .

[29]  Milorad Bojić,et al.  Thermal insulation of cooled spaces in high rise residential buildings in Hong Kong , 2002 .