References of "Nguyen, Anh Tuan"
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See detailA climate analysis tool for passive heating and cooling strategies in hot humid climate based on Typical Meteorological Year data sets
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Energy & Buildings (2014), 68(Part C), 756-763

Through a newly developed climate analysis tool, this paper examines the potential of improving thermal comfort under the climates of Vietnam thanks to passive strategies. A Building climatic chart for ... [more ▼]

Through a newly developed climate analysis tool, this paper examines the potential of improving thermal comfort under the climates of Vietnam thanks to passive strategies. A Building climatic chart for Vietnamese was proposed based on Fanger’s theory [1] and the comfort zone of this chart was then extended by calculating the effects of passive heating and cooling strategies. Typical Meteorological Year weather data are used for extracting and graphically printing of hourly environmental parameters on the psychrometric chart and for climate analysis, subsequently. The limitation and the scope of this method are also specified. The climates of three climatic regions in Vietnam have been used as case studies using all year, seasonal and monthly analysis. The results show that natural ventilation is an effective cooling solution as thermal comfort improvement varies with the climatic zones, increasing from 24.8% in Hanoi, 22.1% in Danang to 32.0% in Hochiminh city. Meanwhile, passive solar heating is only effective under the climate of Hanoi. Direct evaporative cooling also shows great cooling potential for comfort improvement but probable elevated humidity is not expected. Total possible comfort in a year of each location indicates that further climate modification methods are inevitable to achieve comfort during extreme weather conditions, especially in Hanoi. [less ▲]

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See detailA review on simulation-based optimization methods applied to building performance analysis
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg; Rigo, Philippe ULg

in Applied Energy (2014), 113

Recent progress in computer science and stringent requirements of the design of “greener” buildings put forwards the research and applications of simulation-based optimization methods in the building ... [more ▼]

Recent progress in computer science and stringent requirements of the design of “greener” buildings put forwards the research and applications of simulation-based optimization methods in the building sector. This paper provides an overview on this subject, aiming at clarifying recent advances and outlining potential challenges and obstacles in building design optimization. Key discussions are focused on handling discontinuous multi-modal building optimization problems, the performance and selection of optimization algorithms, multi-objective optimization, the application of surrogate models, optimization under uncertainty and the propagation of optimization techniques into real-world design challenges. This paper also gives bibliographic information on the issues of simulation programs, optimization tools, efficiency of optimization methods, and trends in optimization studies. The review indicates that future researches should be oriented towards improving the efficiency of search techniques and approximation methods (surrogate models) for large-scale building optimization problems; and reducing time and effort for such activities. Further effort is also required to quantify the robustness in optimal solutions so as to improve building performance stability. [less ▲]

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See detailPassive designs and strategies for low-cost housing using simulation-based optimization and different thermal comfort criteria
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Journal of Building Performance Simulation [=JBPS] (2014), 7(1), 68-81

An optimum design of low-cost housing offers low-income urban inhabitants great opportunities to obtain a shelter at an affordable price and acceptable indoor thermal conditions. In this paper, the design ... [more ▼]

An optimum design of low-cost housing offers low-income urban inhabitants great opportunities to obtain a shelter at an affordable price and acceptable indoor thermal conditions. In this paper, the design and operation of a low-cost dwelling were numerically optimized using a simulation-based approach. Three multi-objective cost functions including construction cost, thermal comfort performance and 50-year operating cost were applied for naturally ventilated and air-conditioned buildings. Thermal environment inside the house was controlled and assessed by two thermal comfort models. Optimization problems which consist of 18 design parameters and 6 ventilation strategies were examined by two population-based probabilistic optimization algorithms (particle swarm optimization and hybrid algorithm). Optimum designs corresponding to each objective function, differences in optimal solutions, energy saving by the adaptive comfort approach and optimization effectiveness were outlined. The optimization method used in this paper shows a considerable potential of comfort improvement, energy saving and operating cost reduction. [less ▲]

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See detailSustainable housing in Vietnam: Climate responsive design strategies to optimize thermal comfort
Nguyen, Anh Tuan ULg

Doctoral thesis (2013)

Housing issue in Vietnam is still a big concern as in 2008, 72.2% of the existing housing was semi-permanent or temporary and 89.2% of the poor did not have a permanent shelter. As a response to ... [more ▼]

Housing issue in Vietnam is still a big concern as in 2008, 72.2% of the existing housing was semi-permanent or temporary and 89.2% of the poor did not have a permanent shelter. As a response to sustainability, the global aim of this thesis is to develop design strategies toward comfortable, energy-efficient housing with acceptable building cost. Occupants’ thermal comfort is the key assessment criterion throughout the research. <br />First of all, the thesis develops a thermal comfort model for Vietnamese people living in naturally ventilated buildings through the data from field surveys around South-East Asia. This comfort model is then validated by survey data in Vietnam in 2012. <br />A new simple climate analysis tool is developed, used to analyze the climate of 3 regions in question and to draw preliminary design guidelines. A comprehensive study on climate responsive design strategies of vernacular housing in Vietnam is also carried out. The results to some extend reveal the remaining values of vernacular architecture and provide valuable lessons for modern applications. <br />Three most common housing prototypes in Vietnam are selected. Afterward a comprehensive framework is implemented to derive thermal performances of 3 typical housing types. Various techniques (in situ monitoring, building thermal simulation, CFD and airflow network model, numerical model calibration, parametric simulation method) are employed to improve the thermal performances and natural ventilation of these houses. <br />The sensitivity of building performance to the design variables is outlined by Monte Carlo-based sensitivity analysis. The thermal performances of the reference cases are optimized using the simulation-based optimization method and the most influential design variables. Optimization results show the best combinations of design strategies for each climatic region. The performances of the optimal solutions are compared with the references, providing an insight of the efficiency of this approach in building design. <br />Finally, the different objectives yielded in this thesis are summarized. The possible future extensions of this research are outlined. [less ▲]

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See detailOptimum design of low-cost housing in developing countries using nonsmooth simulation-based optimization
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Proceedings of the 28th International PLEA Conference (2012, November 07)

An optimum design of Low-cost housing (LCH) offers low-income urban inhabitants great opportunities to obtain a shelter at affordable price and acceptable indoor thermal conditions. In the present study ... [more ▼]

An optimum design of Low-cost housing (LCH) offers low-income urban inhabitants great opportunities to obtain a shelter at affordable price and acceptable indoor thermal conditions. In the present study, the design and operation of a low cost dwelling were numerically optimized using simulation-based approach in which a dynamic building simulation program (EnergyPlus) was coupled with the optimization engine (GenOpt). Three multi-objective cost functions which include construction cost, indoor thermal comfort and 50-year operating cost were applied for naturally ventilated (NV) and air-conditioned (AC) buildings. Optimization problem which consists of 18 building parameters combined with 6 ventilation strategies was examined by two population-based optimization algorithms (Particle Swarm optimization and Hybrid algorithm) to find optimum combinations among these variables. The results show that the design requirements of NV and AC dwellings are not quite similar, and in a few categories, even contradictory. Optimum design corresponding to each cost function was outlined. Results of this paper also show great potential of optimization in comfort improvement, energy saving, life cycle cost, up to 40%. [less ▲]

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See detailAn adaptive thermal comfort model for hot humid South-East Asia
Nguyen, Anh Tuan ULg; Singh, Manoj Kumar ULg; Reiter, Sigrid ULg

in Building & Environment (2012), 56

The present paper presents a full procedure to develop an adaptive comfort model for South-East Asia. Meta-analysis on large number of observations from field surveys which were conducted in this region ... [more ▼]

The present paper presents a full procedure to develop an adaptive comfort model for South-East Asia. Meta-analysis on large number of observations from field surveys which were conducted in this region was employed. Standardization and bias control of the database were fully reported. Statistical tests of significance and weighted regression method applied in the analyses strengthened the reliability of the findings. This paper found a great influence of ‘Griffiths constant’ on the establishment of adaptive comfort equation and proposed an appropriate value. The adaptive comfort model generated is applicable to naturally ventilated building under hot and humid conditions of South-East Asia. The mean neutral comfort temperature (operative temperature, effective temperature, standard effective temperature) in naturally ventilated and air-conditioned building was compared and the differences have been discussed. The similar neutral standard effective temperature in both naturally ventilated and air-conditioned building proposes a new idea to implement SET* into building simulation tools to assess thermal comfort without the attention of building classification. Through the analysis, the effectiveness of behavioral adaptive actions on occupant’s thermal perception has been argued. The extended PMV-PPD model for hot humid conditions was examined and its applicability was recommended. Other comfort related issues, the differences and similarities between various adaptive comfort models were also addressed. [less ▲]

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See detailAn investigation on thermal performance of a low cost apartment in hot humid climate of Danang
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Energy and Buildings (2012), 47

Low cost apartment has recently become one of the essential state policies to deal with rapid urbanisation and population boom in Vietnam. Thermal performance of a low cost apartment in Danang was ... [more ▼]

Low cost apartment has recently become one of the essential state policies to deal with rapid urbanisation and population boom in Vietnam. Thermal performance of a low cost apartment in Danang was examined using building simulation approach. The simulated results created by COMFIE were first calibrated by comparing them with measured data. The statistical indicators CV(RMSE) and NMBE as well as linear regression analysis were applied to assess the calibration. The calibrated model was then used to perform whole year simulations in which various ventilation and design strategies were applied. Thermal comfort potentials of these strategies were graphically defined by Brager’s adaptive comfort model from which the efficiency of each strategy was quantitatively determined. In the present paper, details of the calibration approach, assessment of simulated results and comparison of the findings were discussed. Results of these analyses revealed many notable findings which are in good agreement with those obtained from other publications. The limitation and recommendations for further study are also outlined. [less ▲]

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See detailAnalysis of Passive cooling and heating potential in Vietnam using Graphical Method and Typical Meteorological Year weather file
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Proceedings of CISBAT 2011 (2011, September 15)

This paper studies the potential to improve thermal comfort in Vietnam thanks to passive strategies. First, a thermal comfort zone for the Vietnamese is proposed by using the PMV-PPD heat balance model of ... [more ▼]

This paper studies the potential to improve thermal comfort in Vietnam thanks to passive strategies. First, a thermal comfort zone for the Vietnamese is proposed by using the PMV-PPD heat balance model of Fanger and the effects of adaptive mechanism of the people living in tropical hot humid region. Then, the comfort zone is enlarged using the algorithms proposed by the authors to calculate the effects of the passive heating and cooling strategies. Typical Meteorological Year (TMY) weather data are used for graphically printing of hourly environmental parameters on the psychrometric chart and for climate analysis, subsequently. The limitation and the scope of this method are also specified. Results of this study show that in all climatic zones of Vietnam, natural ventilation is an efficient cooling solution, low-cost and easy to apply. Thermal comfort improvement of natural ventilation strategy varies with the climatic zones, increasing from 17.1% in Hanoi, 21% in Danang to 31.4% in Hochiminh city. Meanwhile, passive solar heating is not really effective since winter in Vietnam is usually not too cold and the capacity of the passive solar collector system is usually limited. Direct evaporative cooling also has a great cooling effect compared with that of natural ventilation, but significant humidity augmentation in the air in hot and humid conditions may be inappropriate. Seasonal analysis reveals that natural ventilation gives higher performance than other methods and is particularly effective in mild seasons. During 12 months in Hanoi, the analysis clearly shows significant contribution of natural ventilation in the period from April to October during which comfort period achieved might vary from 30% to 81%. The combination of all passive strategies considerably improves thermal comfort: 22.6%, 31.7% and 47.6% of total time in Hanoi, Danang and Hochiminh city, respectively. Finally, the findings of this study indicate that conventional heating and cooling methods are also needed during extreme weather conditions in summer and winter, especially in Hanoi. [less ▲]

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See detailAn investigation on climate responsive design strategies of vernacular housing in Vietnam
Nguyen, Anh Tuan ULg; Tran, Quoc Bao; Tran, Duc Quang et al

in Building & Environment (2011), 46

Energy conservation issues and environmental problems in recent years have increased interest in traditional architecture which is well known for its energy saving designs. This paper thoroughly ... [more ▼]

Energy conservation issues and environmental problems in recent years have increased interest in traditional architecture which is well known for its energy saving designs. This paper thoroughly investigates vernacular housing designs and evaluates on the aspect of building physics. A new research methodology which is adapted to the natural and social context of Vietnam was proposed and applied. The process was carried out step by step, including: climate zoning, systematic analysis, in-situ survey and building simulations. The results of this study indicate that vernacular housing in Vietnam is creatively adapted to the local natural conditions and uses various climate responsive strategies. Through this study, the most frequently used strategies and their effectiveness were derived. The authors also found that under extreme weather conditions, traditional designs might not be sufficient to maintain indoor thermal comfort. [less ▲]

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See detailThe effect of ceiling configurations on indoor air motion and ventilation flow rates
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Building & Environment (2011), (46), 1211-1222

The purpose of this paper is to evaluate the effects of a building parameter, namely ceiling configuration, on indoor natural ventilation. The computational fluid dynamics (CFD) code Phoenics was used ... [more ▼]

The purpose of this paper is to evaluate the effects of a building parameter, namely ceiling configuration, on indoor natural ventilation. The computational fluid dynamics (CFD) code Phoenics was used with the RNG k-ɛ turbulence model to study wind motion and ventilation flow rates inside the building. All the CFD boundary conditions were described. The simulation results were first validated by wind tunnel experiment results in detail, and then used to compare rooms with various ceiling configurations in different cases. The simulation results generated matched the experimental results confirming the accuracy of the RNG k-ɛ turbulence model to successfully predict indoor wind motion for this study. Our main results reveal that ceiling configurations have certain effects on indoor airflow and ventilation flow rates although these effects are fairly minor. [less ▲]

Detailed reference viewed: 104 (36 ULg)