Thermodynamics Evaluation Methodology And Software Research Of Building Envelope

In our country, most of the existing buildings and new buildings are high energyconsumption buildings which seriously restrict the sustainable development ofeconomy and bring a series of environmental pollution. The current availableevaluation systems of building energy saving mainly evaluate t he quantity of energyconsumption without consideration of energy consumption quality and effects onenvironment, therefore their results are usually with some errors.In this paper, the influences of stages of building material production andbuilding operation are considered comprehensively combined with lifecycle theoryand the conception of exergy is introduced to more objectively evaluate the useefficiency of energy by comprehensively considering the quantity and quality ofenergy. The energy consumption, exergy consumption and co2emission of buildingenvelops in the stages of building material production and building operation arecalculated and analyzed with the thoughts and methods in thermo economics.The calculation formula of exergy cost per outer building envelope area ispresented and an evaluation software of exergy cost of building envelope is developedby Access and VB6.0based on the above thoughts and the derived calculation formula.The software can be used to calculate the energy consumption, exergy consumptionand co2emission of building envelops in the stages of building material productionand building operation, and exergy cost of building envelopes and compare andanalyze schemes of different buildings with different predicted opera tion time, andthe general situation of building can be displayed with columnar section. It usingmethod is demonstrated in the end of this paper.Considering the complexity of building materials, a method using referencematerial, comprehensive equivalent coefficient of thermodynamic cost andrelationship between engineering cost and energy consumption, exergy consumptionand co2emission is proposed to estimate energy consumption and exergy consumptionof building material.