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Fu X.Z.,Nanjing Southeast University | Fu X.Z.,Key Laboratory of Urban and Architectural Heritage Conservation | Dong J.,Nanjing Southeast University
Applied Mechanics and Materials | Year: 2014

There are several factors impacting on the indoor airflows, such as building openings, ambient wind speed, occupants' behavior and so forth. This paper concentrates on the impact of windows and interior doors on airflows in a rural multi-storey residential building. The indoor airflow simulation was carried out by using the CFD software. 3 states of interior doors were set, and 60 regions were arrayed in bedroom to observe the variation of airflows. According to data of regions, the uniformity of airflow and the thermal comfort were analyzed. Simulation results identified that closing interior doors will increase the mean age of indoor air about 7 times as it under the condition of opening doors, which is from 90s to 666s. It also shows that transom windows is beneficial to improve natural ventilation efficiency, as it can raise the average wind velocity by 40% when interior doors are closed. © (2014) Trans Tech Publications, Switzerland.

Shi X.,Nanjing Southeast University | Shi X.,Key Laboratory of Urban and Architectural Heritage Conservation | Tian Z.,Nanjing Southeast University | Tian Z.,Key Laboratory of Urban and Architectural Heritage Conservation | And 6 more authors.
Renewable and Sustainable Energy Reviews | Year: 2016

Energy efficiency is a mandatory requirement and integral part of green and sustainable buildings. Energy efficient design optimization is both a design philosophy and a practical technique that has been proposed and used by architects and other professionals for several decades, especially in the past few years. In this review, a set of selection criteria are proposed and 116 works are identified as the core literature. Taking the perspective of architects, analysis is conducted to the core literature to reveal the state of the art of building energy efficient design optimization. The analyzed subjects include the general procedure, the origin and development, the classification, the design objectives and variables, the energy simulation engines, the optimization algorithms, and the applications. The review findings confirm that building energy efficient design optimization is a promising technique to design buildings with higher energy efficiency and better overall performance. However, obstacles still exist and future research is needed. © 2016

Xiong T.Y.,Nanjing Southeast University | Fu X.Z.,Nanjing Southeast University | Fu X.Z.,Key Laboratory of Urban and Architectural Heritage Conservation | Dong J.,Nanjing Southeast University
Advanced Materials Research | Year: 2014

Rural dwellings have a big difference in the appearance and envelope. Living form is changing a lot from detached house to the apartment in multi-story apartments. These changes affect building's energy consumption consisting of heating and cooling. This paper focuses on the impact of the energy consumption affected by different surface volume ratios, simulation analysis showed a general argument of the difference. And for the same house type, this paper also compares the energy-saving effect of different envelop performances, Specific contents are the heat transfer coefficient and shading ways. Simulation results identified that SVR has influence on different types of houses, the energy consumption of row houses can be saved more than 30% compared with detached houses. Envelope performance also affects energy consumption and the national standard is recommended for the energy saving and the comfort. © (2014) Trans Tech Publications, Switzerland.

Si B.,Nanjing Southeast University | Si B.,Key Laboratory of Urban and Architectural Heritage Conservation | Tian Z.,Nanjing Southeast University | Tian Z.,Key Laboratory of Urban and Architectural Heritage Conservation | And 8 more authors.
Energy | Year: 2016

Building energy efficient design optimization is an emerging technique that is increasingly being used to design buildings with better overall performance and a particular emphasis on energy efficiency. To achieve building energy efficient design optimization, algorithms are vital to generate new designs and thus drive the design optimization process. Therefore, the performance of algorithms is crucial to achieving effective energy efficient design techniques. This study evaluates algorithms used for building energy efficient design optimization. A set of performance indices, namely, stability, robustness, validity, speed, coverage, and locality, is proposed to evaluate the overall performance of algorithms. A benchmark building and a design optimization problem are also developed. Hooke–Jeeves algorithm, Multi-Objective Genetic Algorithm II, and Multi-Objective Particle Swarm Optimization algorithm are evaluated by using the proposed performance indices and benchmark design problem. Results indicate that no algorithm performs best in all six areas. Therefore, when facing an energy efficient design problem, the algorithm must be carefully selected based on the nature of the problem and the performance indices that matter the most. © 2016 Elsevier Ltd

Shi X.,Key Laboratory of Urban and Architectural Heritage Conservation | Shi X.,Nanjing Southeast University
Energy | Year: 2011

Architectural design is a process to find the best solution to satisfy various design criteria. To achieve sustainable and green design, performance simulations are often used to verify these criteria and modify the design. The conventional approach of manual trial-and-error is too time-consuming to be practical. Introducing optimization technique can greatly improve the design efficiency and help designers find the optimal design. In this paper, modeFRONTIER was used as the design optimization environment to find the best insulation strategy to minimize the space conditioning load of an office building located in Nanjing, China while keeping the insulation usage at minimum. EnergyPlus was integrated into the optimization tool by writing a DOS batch file to automate the work flow. The search engine was the genetic algorithm and it proved to be able to generate a well-defined Pareto frontier in a reasonable number of runs. Based on the Pareto frontier, the designer can specify his preferences and select the final design. The case study shows that an energy simulation program can be effectively integrated into a design optimization environment to find the optimal design. The technique presented has a broad application in architectural design, especially when the design considerations are multi-objective. © 2011 Elsevier Ltd.

Shi X.,Nanjing Southeast University | Shi X.,Key Laboratory of Urban and Architectural Heritage Conservation | Zhu Y.,China Academy of Building Research | Duan J.,Nanjing Southeast University | And 3 more authors.
Landscape and Urban Planning | Year: 2015

Pedestrian wind environment is one of the urban physical environments that have a significant impact on the overall wellbeing of a city and its dwellers. It is important to be able to assess pedestrian wind environment in the urban planning design stage. Such assessment is intrinsically an in-design assessment and should be based on spatial analysis. The methodology developed considers the probabilistic nature of the assessment by determining an 80-percentile ambient wind speed as the boundary condition for wind environment simulation. The assessing criteria include mechanical comfort, safety, and amplification factor. Their threshold values are based on comparisons of existing criteria. In addition, the concept of tolerance factor, which takes into account the psychological effects of different urban spaces on people, is integrated into the assessment system. The assessment methodology can be used by urban planners in parallel with the process of designing urban physical spaces. A case study of the downtown area of an urban planning project near Lake Tai in China is conducted to demonstrate the application of the assessment methodology. Two limitations of the methodology need to be noted. First, it relies on CFD techniques to obtain the wind environment and therefore, the simulation must be conducted with considerable care and circumspection. Secondly, the methodology does not include the thermal and ventilation effects of pedestrian wind. © 2015 Elsevier B.V.

She W.,Jiangsu Research Institute of Building Science | She W.,Nanjing Southeast University | She W.,University of Dundee | Jones M.R.,University of Dundee | And 3 more authors.
International Journal of Architectural Heritage | Year: 2015

The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone. © Taylor and Francis Group, LLC.

Fu X.,Nanjing Southeast University | Fu X.,Key Laboratory of Urban and Architectural Heritage Conservation | Wu D.,Nanjing Southeast University
Applied Mechanics and Materials | Year: 2012

Hybrid ventilation has significant advantages in building energy-saving. We discussed the potential and influencing factors of the rational use of building hybrid ventilation systems in three typical cities, located in three different climate regions of China. We used the Adapted Comfort Standard (ACS) model and Energyplus software to analyze the hybrid ventilation efficiency. This method combines the advantages of Degree-Hours Method and Heat Balance Method, and also takes into account the wind-driven and buoyancy-driven models. Results shows that the natural ventilation potential (NVP) utilization hours of high thermal insulation buildings with temperature control ventilation can be up to 5080h in Beijing, 6195h in Nanjing and 6726h in Guangzhou, accounting for 58.0%, 70.7% and 76.8% of the full year respectively. It means that the rational use of hybrid ventilation and ventilation mode can significantly reduce building energy consumption in summer. © (2012) Trans Tech Publications, Switzerland.

Qian K.,Key Laboratory of Measurement and Control of Complex Systems of Engineering | Qian K.,Nanjing Southeast University | Ma X.,Key Laboratory of Measurement and Control of Complex Systems of Engineering | Ma X.,Nanjing Southeast University | And 6 more authors.
International Journal of Smart Home | Year: 2014

In this paper, the design and development of a Building Energy and Environment Monitoring System (BEEMS) for smart campus applications is proposed. The system is implemented based on distributed sensor nodes using ZigBee technology, which empowers the collection and monitoring of various types of measurements that reflect the energy consumption and environmental status of buildings. These parameters include temperature, humidity, air velocity, sound, bubble globe temperature, TVOC, CO2 concentration, air quality level, et al. The application software system is developed using jQuery-based Ajax general interactive architecture, and further integrated with campus GIS, which offers rich analysis and report functions for monitoring both energy consumption and environment parameters. © 2014 SERSC.

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