Simulation and comparison of insulation performance of vitrified microbead insulation mortar based on EnergyPlus

Fund Project: The Doctoral Fund of the Ministry of Education (New Teacher) Project (20101402120007) Green building has become the basic trend of building development at present, and the countries in the world are constantly changing in the technology and application of green building. The greening of buildings and existing buildings has also developed greatly, marking the awakening of human environmental awareness and sustainable development awareness. “Urban cave dwelling” type green building, also known as integral thermal insulation building, its key technology is the study of heat preservation load-bearing coagulation of Journal of North University of China (Natural Science Edition), performance optimization of vitrified micro-bead insulation mortar, overall The research on the thermal insulation system is a new type of construction system proposed by the research group to introduce the advantages of the traditional soil cavern hot and humid environment into the design concept of modern architecture according to the requirements of establishing a resource-saving and environment-friendly society. Green building requirements. In this paper, the integral heat preservation is the smear integral heat preservation system, which can be realized by the mature construction technology of the traditional plastering mortar, which can better guarantee the engineering quality and the heat preservation effect.

This paper takes a typical medium-sized office building as an example, and compares the insulation performance of ordinary mortar and vitrified microbead insulation mortar with a new generation of building energy consumption analysis software EnergyPlus. The simulation results show that the inner and outer thermal insulation layers of vitrified micro-bead insulation mortar have great savings on the winter energy consumption of the building.

1 Model Overview Take a typical medium-sized office building as an example to compare the impact of ordinary mortar and vitrified micro-bead insulation mortar on building energy consumption. The building has 10 floors, 6 rooms per floor, a total of 60 rooms. Since EnergyPlus can simplify modeling by specifying the number of repeats of the hot zone (Zone), there are only 9 basic hot zones, which are 3 floors, top, standard and bottom. The standard layer has a total of 8 layers, so the number of repetitions of the standard layer is 8; each layer is divided into three basic hot regions of the west and the middle of the middle, and the number of repetitions of the central basic hot zone in each layer is 4. Plus. The 3D visual parameter setting of the model The energy consumption index in this paper is based on the energy saving design standard of residential building (DB04-242-2006). The heating period is 138d, and the average indoor calculation temperature is 16 °C. The vitrified microbead insulation The parameters of the mortar come from.

Plus model parameters: 1 building. Location: Taiyuan, Shanxi; building type and number of floors: office building, 10 floors above ground, height 25m; total floor area: 1 440m2; floor layout and floor height: 4 m<6m for each room, 24mK6m for floor plan, The height of the floor is 25 10a+6 double-layer white glass, the area of ​​each window is 1.0m2 from east to west, and the internal heat load and ventilation of each window area is 20m2.2. Personnel density: 9.29m2 people; lighting intensity: 9.15W/m2; hot water equipment: 31.1W/person. 3 heating system. Heater type: electric heating rice heater, power is automatically determined by EnergyPlus in the simulation of an optimal value; thermal efficiency: Q95.4 enclosure structure. Exterior wall: 30 thick plastering mortar + 200 thick reinforced concrete + 20 thick plastering mortar; interior wall: 20 thick plastering mortar + 200 thick reinforced concrete + 20 thick plastering mortar; window: 6t"10a+ 6 double-layer white glass; floor: 20 thick plastering mortar + 100 thick reinforced concrete + 20 thick plastering mortar; roof insulation waterproof layer: Zhejiang oil felt tile + 200 thick aerated concrete. 5 material parameters. Ordinary plastering Mortar: heat transfer coefficient is Q93W/(m2.K), density 2000kg/m2; vitrified microbead insulation mortar: heat transfer coefficient is 0.06W/(m2.K), density 309 kg/m3; reinforced concrete: heat transfer Coefficient 1.74W/(m2.K), density 2 500kg/m3; aerated concrete: heat transfer coefficient is 0.28W/(m2.K), density 700kg/m3; Zhejiang oil felt tile: heat transfer coefficient is 0.03W/ (m2.K), density 1121kg/m3; window: parameters are automatically calculated by EnergyPlus in the simulation.

3 Results Analysis 3.1 Simulation results. The heating period for calculation is n. 8~3.25, and the energy saving effect is better. The energy unit in the EnergyPlus simulation result is expressed in the international unit system of joules, and is expressed by megajoule and gyroscope according to the size of the data. The conversion relationship between them and the commonly used kw°h, kg standard coal is: 1 The amount of energy consumed for the simulation of the two models, and the other models have 15.5G of hot water for the indoor hot water equipment, for the sake of simplicity The form is only texted here and is not included in the form. Comparing the energy consumption data of the two models, the total energy consumption of the vitrified microbead insulation mortar model is only 56% of the total energy consumption of the ordinary plastering mortar model. The energy saving is entirely from the heating energy consumption, the former is only 19% of the latter. It embodies the energy consumption quantity of the vitrified micro-bead insulation mortar in the simulation results of the heating period. The total energy consumption of the whole building square meters energy consumption Gkg standard coal M / m2kg standard coal ordinary plastering mortar model 342. Mortar model 191. In the simulation results, the heat transfer coefficient of 6h10; +6 double-layer white glass is 2. / (m2.K), and the heat transfer coefficient of the roof insulation waterproof layer is 0.911W / (m2.K). The heat transfer coefficient of the wall has a large difference. The heat transfer coefficient of the inner and outer walls in the vitrified micro-bead insulation mortar model is 0.911W/(m2°K), and the heat transfer coefficient of the inner and outer walls in the ordinary plastering mortar model is 3.141. W/(m2.K), which is 3.45 times that of the former, is the cause of the difference in energy consumption in Table 1.

His heating season date/day in one year (a) ordinary plastering mortar model, heating season, day/day (b) vitrification microballoon thermal insulation mortar model, time-lapse indoor temperature comparison is 9 basic in two models The hot zone is significantly higher in the entire pass-through mortar model. Combined with the heating energy consumption of the two, it can be found that the vitrified micro-bead insulation mortar model maintains a high indoor temperature with less energy consumption, indicating the glass The excellent performance of the micro bead insulation mortar in the insulation of the envelope structure and the corresponding energy saving effect.

3.2 Results Verification The reliability and accuracy of the Plus building energy simulation results can be verified in three ways.

Verification of the reliability of the Plus software itself. The software has been continuously tested in applications by research institutions and commercial users for many years.

Verification of EnergyPlus simulation results based on building energy analysis theory and engineering specifications. Since the theory of building energy consumption analysis is a reasonable approximation of the actual energy consumption process, the calculation formula in the engineering specification has its accuracy requirements, so the calculation result has its accuracy. At present, some domestic and foreign scholars have carried out this verification work in the study of building energy consumption.

The hourly indoor average temperature curve during the warm period. From this, you can look at the project and build two identical comparisons in the three places. The average indoor temperature in the vitrified micro-bead insulation mortar model is compared with the general room, and one of them is installed with an external thermal insulation system for comparative experiments. This is a comparison of field measurements and EnergyPlus simulations of the same building. This kind of comparison and verification is time-consuming and costly. The engineering site conditions are not easy to control and its complex and variability. The requirements of the test equipment and testers are very high. Some process details are not handled properly, which leads to more deviations than theoretical models and software simulations. Difficult to control, any negligence in the field measurement and comparative analysis will make the conclusion too rash. At present, a large number of building energy consumption data have been collected in many urban public building energy consumption monitoring systems. However, the existing building energy consumption data is basically derived from energy consumption statistics.

In 2002, it was initiated by Weikai Company, and together with Beijing, Shanghai and Guangzhou universities and insulation system suppliers to jointly carry out the application of “external thermal insulation system in various climatic conditions”. The quantitative verification of the actual effect of the insulation system was carried out. On the other hand, it also points out the complexity of the actual situation and the limitations of the experiment. It is also insufficient to compare the software simulation.

In recent years, the practice of Passive Buildings in Passive Buildings in Germany shows that strict quality assurance and control testing can make the measured energy consumption level comparable to the design energy consumption level. Since 2009, various houses must provide “energy proof”. The provisions are also based on this level of measurement. This paper does not carry out this comparison verification. Based on the conclusions of the above rigorous work of scientific research projects, this paper has a positive attitude towards the consistency of EnergyPlus simulation results and the actual energy consumption of buildings. In the future research, it is still necessary to design and implement a perfect comparison. The program to really verify.

4 Conclusions and Discussions This paper compares the insulation performance of ordinary mortar and vitrified microbead insulation mortar with a new generation of building energy consumption analysis software EnergyPlus. The simulation results of a typical medium-sized office building show that: in a heating period, The total energy consumption of the vitrified micro-bead insulation mortar inside and outside the building is only 56% of the ordinary plastering mortar construction, the heating energy consumption is only 19% of the latter, and the indoor temperature is significantly higher than the latter, quantitatively verified The excellent thermal insulation and energy saving effect of the vitrified microbead insulation mortar.