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Quantitative assessment of the conservative addition transfer by filtration flow through the wall  [cached]
D.V. Petrosova
Magazine of Civil Engineering , 2012,
Abstract: Effect of air filtration on the temperature and humidity conditions of building structures is significant. This explains the great attention which is paid to the question of air filtering through the building envelope. In the air permeable building envelopes heat flow is carried out including by air filtration. Filtering transfer of conservative addition is comparable with heat transfer by thermal conduction. A method for calculating the heat flow by filtering heat transfer was proposed. Calculation examples for lightweight building envelope were given.
Optimization of thermal comfort in building through envelope design  [PDF]
Milorad Bojic,Alexandre Patou Parvedy,Harry Boyer
Computer Science , 2013,
Abstract: Due to the current environmental situation, energy saving has become the leading drive in modern research. Although the residential houses in tropical climate do not use air conditioning to maintain thermal comfort in order to avoid use of electricity. As the thermal comfort is maintained by adequate envelope composition and natural ventilation, this paper shows that it is possible to determine the thickness of envelope layers for which the best thermal comfort is obtained. The building is modeled in EnergyPlus software and HookeJeves optimization methodology. The investigated house is a typical residential house one-storey high with five thermal zones located at Reunion Island, France. Three optimizations are performed such as the optimization of the thickness of the concrete block layer, of the wood layer, and that of the thermal insulation layer. The results show optimal thickness of thermal envelope layers that yield the maximum TC according to Fanger predicted mean vote.
Determination of the thermal-physical properties of building envelope through the method of non-destructive test applying universal multichannel registration gauge of “Teplograf” / Определение теплофизических свойств ограждающих конструкций зданий методом неразрушающего контроля с использованием универсального многоканального регистратора Теплограф  [cached]
Kovylin A.V. / Ковылин Андрей Васильевич,Fokin V.M. / Фокин Владимир Михайлович
Internet-Vestnik VolgGASU , 2006,
Abstract: The paper gives a method, experiments, calculations for the determination of the thermal-physical properties of construction materials of building envelope through the method of non-destructive test applying the latest electronic gauge. / Приведены методика, эксперименты, расчеты по определению теплофизических свойств строительных материалов ограждающих конструкций зданий методом неразрушающего контроля с использованием новейшего электронного прибора.
Thermal Load Reduction with Green Building Envelope  [PDF]
Dilawar Husain, Sarvesh Shukla, Vivek Kumar Umrao, Ravi Prakash
Open Journal of Energy Efficiency (OJEE) , 2017, DOI: 10.4236/ojee.2017.63009
Abstract: Various studies have confirmed that high thermal resistance in roof & wall can reduce the heat transfer load of the buildings. In this study, experimental investigation of the effects of some sustainable features (such as green roof, reflective coated roof & Fly ash brick (FAB) etc.) on the building has been conducted in the Indian context. For the purpose, two scaled building models i.e. Model I (conventional design) & Model II (green design) have been examined with different design configurations. The sensible heat transfer (SHT) load of the building is reduced by 21% - 29% through the use of FAB with cavity wall in place of Fired clay brick (FCB) wall. The load reduction increases to 26% - 44% by using FAB cavity wall with reflective coating on the roof. This reduction further increases to 64% - 68% with FAB cavity wall along with green roof. In this final scenario, the monthly electrical energy saving for air-conditioning is approximately 5.1 kWhe/m2 per unit envelope area, with associated reduction in GHG emissions up to 6.36 kg CO2eq/m2 per unit envelope area, assuming continuous operation of HVAC systems.
V. V. Ivanov,A. N. Butenko,L. V. Karaseva
Scientific Herald of the Voronezh State University of Architecture and Civil Engineering , 2011,
Abstract: Problem statement. To determine additional heat losses through window opening slopes, it is ne-cessary to calculate temperature fields of a wall in the zone of connection between window and building envelope. Two types of building envelopes are considered: solid brick wall and two-layer-wall of bricks and fiber foam concrete block interlayered with air.Results. The results obtained show the influence of a window on the temperature field of wall opening. Different types of wall structures are investigated. The temperature distribution in the edge zone and in the center of glazing is shown. The problem has been solved on the basis of the finite element method. Heat transfer in the translucent part of the window was studied.Conclusions. The analysis conducted showed that it is possible to calculate considered glazing structures without regard for adjacent wall structures.
The Oppressive Broadband Interference Excision through Envelope Filtering for Pseudo-random Code Phase Modulation Fuze System

Zhang Shu-ning,Zhao Hui-chang,Wang Li-jun,

电子与信息学报 , 2006,
Abstract: The effects of several types of oppressive broadband interference (BPSK interference, FM interference) on pseudo noise coded fuze system are analyzed. It is found that the correlation output is deteriorated when the interference power is larger than the anti-interference limit of the fuze system. So it is very necessary to excise the above interference before correlation. A new simple technique of excising interference through envelope filtering is put forward. The received signal is quadrature demodulated to inphase and quadphase signal. The instantaneous envelope and phase are got with the inphase and quadphase signal. The envelope of interference is obtained by envelope notch filtering in the frequency domain. The interference is reconstructed using the notched envelope sequence and the phase sequence. Then the reconstructed interference is subtracted from the received signal. It is found by simulation that the technique proposed in this paper can effectively excise the broadband interference, especially for strong interference. And the correlation output is improved obviously. The technique is easy to be understood. It has low computational complexity and therefore is easy to realize.
Environmental Impact on Building Envelope: A Case Study for New Mosque Design in Baghdad  [PDF]
Akeel Noori Abdul Hameed
International Transaction Journal of Engineering, Management, & Applied Sciences & Technologies , 2011,
Abstract: The work is carried out with an objective of first, evaluating: the thermal characteristics of opaque and transparent parts of the building envelope in hot dry climate of case study “new mosque” building in Baghdad, the impact of sol-air temperatures, heat gain factors and the u-value of envelope section components. Second, it aims to assess the architectural criteria for appropriate passive design of new mosques in hot dry climates. Architectural design and construction of the new mosque (musalla) envelope in Baghdad are thermally inefficient in protecting the indoor space from climatic fluctuations. Therefore, the existing new mosques are not within thermal comfort level. To achieve and maintain that, applying architectural and construction alternatives on the mosque envelope contributes to controlling heat exchange through it as well as enhancing its thermal behaviors that contribute to getting internal thermal balance. The research covers survey of design, construction features, comfort levels in new mosques, and definition of the “model mosque”, as well as identification and thermal assessment of the typical “model mosque”. Computer simulations for building thermal behavior and design modification of building construction components also covered by the research. The findings and conclusion of the impact of simulation changes stated as well as recommendations for possible future mosque and design strategy. The findings show that HVAC systems entail capital, functional and maintenance costs whereas the passive mosque (musallas) building consumes less energy as well as being more likely to be in sympathy with the environment.
Influence of building envelope thermal protection on heat loss value in the building (rus)
Vatin N.I.,Nemova D.V.,Rymkevich P.P.,Gorshkov A.S.
Magazine of Civil Engineering , 2012,
Abstract: The research presents the calculations for the heat losses through the envelope of the apartment building. The calculations are provided for different levels of insulation of enclosing structures (i.e. wall, windows, roof etc) according to three normative documents: Set of rules 50.13330.2012 (rus), Construction Norms and Regulations 23-02-2003 (rus) and National Building Code of Finland, Part D3 (fin). The impact of level of thermal protection of external enclosure structures on the values of heat losses, the operating costs and the costs of fuel and energy resources during the heating period (for 10, 30 and 50 years of upkeep of buildings) on the example of the one habitable apartment building is analyzed. Calculation of payback periods of the energy saving actions directed on increase of level of thermal protection of external enclosure structures of buildings is given. Economic efficiency of investments in energy saving measures is analyzed.
Ventilated Double Window for the Preheating of the Ventilation Air Comparison of Its Performance in a Northern and a Southern European Climate  [PDF]
Jorge S. Carlos,Helena Corvacho
Journal of Renewable Energy , 2013, DOI: 10.1155/2013/290865
Abstract: Keeping the indoor air quality within the reference levels requires that the polluted indoor air be replaced by fresh air coming from the outside. This paper presents a sensitivity analysis and a series of simulations where the performance of this passive system is studied. The influence of each relevant factor, like the wind, the solar radiation, and the outdoor air temperature, is assessed. Two different local sets of climatic data were chosen, a mild and a cold winter. 1. Introduction Buildings envelope has been optimized over the last decades assuring a better insulation between the indoors and the outdoors, thus reducing heat transfer through the construction elements. Part of the thermal losses of a building takes place through the necessary renewal of the indoor air to maintain a good air quality for the inhabitants. Increasing thermal resistance of buildings envelope leads to an increasing relative importance of heat losses through ventilation. Those losses may come to represent an important percentage in the overall thermal losses. Energy Research Group [1] points to 20% to 40% of heat loss by the renewal of air in homes in central Europe, with an increase to 70% in buildings well thermally insulated. Various technologies and building systems have been developed to reduce the impact of climate, thus reducing the energy consumption of buildings. A survey of studies on buildings facades is listed by Quesada et al. [2, 3] where active and passive solar facade solutions, either opaque or nonopaque, are presented. Sadineni et al. [4] made a review of building envelope components and respective improvements from an energy efficiency perspective. Preheating of the ventilation air in winter has also been studied in the last decades. A study was done and a model was proposed by Woods et al. [5] to reduce energy consumption due to ventilation by heating the air through an atrium of large public buildings. In fact, several possible ways of preheating the ventilation air are available. “For a high insulated house or low energy house, the minimum heating requirement should be supplied by heating the supply air in the ventilation system—a system which is necessary in any case,” as it was referred by Persson et al. [6]. The unglazed transpired solar collectors [7], the solar air collector mounted on sun-facing walls [8] or on the roof, the ventilated photovoltaic facade [9] with an air channel between the photovoltaic panel and the facade, the ventilated double glazed facade [10], the window air collector [11], the supply air window [12], and the ventilated
Energy-Saving Potential of Building Envelope Designs in Residential Houses in Taiwan  [PDF]
Chi-Ming Lai,Yao-Hong Wang
Energies , 2011, DOI: 10.3390/en4112061
Abstract: The key factors in the energy-saving design of a building’s exterior in Taiwan are the thermal performance of the roof and window glazing. This study used the eQUEST software to investigate how different types of roof construction, window glasses and sunshield types affect the energy consumption in residential buildings under common scenarios. The simulation results showed that the use of an appropriate window glass significantly reduced the annual energy consumption, followed by the shading device, whereas the roof construction produced less of an energy-efficiency benefit. By using a low-E glass and a 1.5 × 1.5 m box shading (e.g., balcony), this could save approximately 15.1 and 13.6% of the annual electricity consumption of air conditioners, respectively. Therefore, having control over the dominant factors in the building envelope is indeed an important step in the path to achieving energy savings and carbon reduction in residential houses.
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