scholarly journals Window Design of Naturally Ventilated Offices in the Mediterranean Climate in Terms of CO2 and Thermal Comfort Performance

2020 ◽  
Vol 12 (2) ◽  
pp. 473 ◽  
Author(s):  
Hardi K. Abdullah ◽  
Halil Z. Alibaba
Keyword(s):  
Thermal Comfort ◽  
Natural Ventilation ◽  
Mediterranean Climate ◽  
Computational Modelling ◽  
Co2 Concentration ◽  
The North ◽  
Adaptive Thermal Comfort ◽  
Adaptive Comfort ◽  
The Mediterranean ◽  
Window Design

Natural ventilation through window openings is an inexpensive and effective solution to bring fresh air into internal spaces and improve indoor environmental conditions. This study attempts to address the “indoor air quality–thermal comfort” dilemma of naturally ventilated office buildings in the Mediterranean climate through the effective use of early window design. An experimental method of computational modelling and simulation was applied. The assessments of indoor carbon dioxide (CO2) concentration and adaptive thermal comfort were performed using the British/European standard BS EN 15251:2007. The results indicate that when windows were opened, the first-floor zones were subjected to the highest CO2 levels, especially the north-facing window in the winter and the south-facing window in the summer. For a fully glazed wall, a 10% window opening could provide all the office hours inside category I of CO2 concentration. Such an achievement requires full and quarter window openings in the cases of 10% and 25% window-to-floor ratios (WFR), respectively. The findings of the European adaptive comfort showed that less than 50% of office hours appeared in category III with cross-ventilation. The concluding remarks and recommendations are presented.

scholarly journals Adaptive Thermal Comfort Potential in Mediterranean Office Buildings: A Case Study of Torre Sevilla

2018 ◽  
Vol 10 (9) ◽  
pp. 3091 ◽  
Author(s):  
Raúl Castaño-Rosa ◽  
Carlos Rodríguez-Jiménez ◽  
Carlos Rubio-Bellido
Keyword(s):  
Thermal Comfort ◽  
Air Conditioning ◽  
Natural Ventilation ◽  
High Tech ◽  
Adaptive Thermal Comfort ◽  
Adaptive Comfort ◽  
Conditioning Equipment ◽  
Air Conditioning Systems ◽  
The City

The design and construction of buildings is currently subject to a growing set of requirements concerning sustainability and energy efficiency. This paper shows a case study of the Torre Sevilla skyscraper, located in the city of Seville (in the south of Spain), which has high-tech energy-efficient features and which uses air-conditioning systems during most of its operating hours. The analysis carried out starts from a simulation in which occupants’ thermal comfort are obtained, based on the adaptive comfort model defined in the standard EN 15251:2007. With this approach, it is possible to determine the number of hours during operation in which the building has adequate comfort conditions only with the help of the envelope and natural ventilation. Consequently, the remaining useful hours require the use of air-conditioning systems. The results show that it is possible to improve the thermal performance of the building due to its location in the Mediterranean climate. To do this, advanced mixed mode (through manual-opening or mechanically-controlled opening windows) and active air-conditioning are suggested. This experimental proposal provides a reduction of the occupation hours which require the use of air-conditioning equipment by 28.57%, reducing the air-conditioning demand and, consequently, the energy consumption of the building.

scholarly journals Field study on adaptive thermal comfort models for nursing homes in the Mediterranean climate

2021 ◽  
pp. 111475
Author(s):  
N. Forcada ◽  
M. Gangolells ◽  
M. Casals ◽  
B. Tejedor ◽  
M. Macarulla ◽  
...  
Keyword(s):  
Nursing Homes ◽  
Thermal Comfort ◽  
Field Study ◽  
Mediterranean Climate ◽  
Adaptive Thermal Comfort ◽  
The Mediterranean

scholarly journals Long-Term Productivity of Thirteen Lowland and Upland Switchgrass Ecotypes in the Mediterranean Region

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 923
Author(s):  
Efthymia Alexopoulou ◽  
Federica Zanetti ◽  
Eleni G. Papazoglou ◽  
Konstantinos Iordanoglou ◽  
Andrea Monti
Keyword(s):  
Panicum Virgatum ◽  
Mediterranean Climate ◽  
Biomass Crop ◽  
The North ◽  
Panicum Virgatum L ◽  
The Usa ◽  
Biomass Yields ◽  
The Mediterranean ◽  
Marginal Soil

Switchgrass (Panicum virgatum L.) has been identified in the USA as an ideal biomass crop, in relation to its wide environmental suitability, mainly linked to the availability of both upland and lowland ecotypes, allowing the possibility of growing this species in most of the North American region. Switchgrass is conventionally grown for forage, but more recently, it has been considered as a model biofuel crop. Early European studies on switchgrass as a bioenergy crop started in the late 1990s, when a multi-location field trial was established in Greece (Aliartos) and Italy (Ozzano) to compare the productivity of 13 switchgrass genotypes, including upland (Carthage, Blackwell, Caddo, CIR, Forestburg, SU 94-1, Summer) and lowland (Alamo, Kanlow, Pangburn, SL 93-2, SL 93-3, SL94-1) genotypes. The scope was to identify the most suitable ecotype within each environment and, possibly, the best performing variety. The trials lasted 17 years (1998–2014) in Greece and 13 years (1998–2010) in Italy. While in Italy the trial was rainfed and unfertilized, in Greece, where the soil was marginal, drip irrigation was always applied, and the plots were fertilized regularly. The biomass yields in Greece, as averages across the 17 years, were similar for the lowland and upland varieties (11.5 vs. 11.1 Mg ha−1, respectively), while in Italy, as averages across the 13 years, the differences were relevant: 15.4 vs. 11.3 Mg ha−1 for lowland and upland, respectively. Alamo (lowland) was the most productive variety, both in Greece and Italy, with average annual yields of 12.7 and 16.6 Mg ha−1, respectively; CIR in Greece (10.1 Mg ha−1) and Forestburg in Italy (9.1 Mg ha−1) (both upland) were the least productive genotypes. The present results demonstrate the good suitability of switchgrass as biomass crop for the Mediterranean climate. Despite the very marginal soil (i.e., very shallow and with a sandy texture) in the Greek trial, the application of regular fertilization and irrigation produced biomass yields above 11 Mg ha−1 (grand mean) in the present 17-year-long study.

scholarly journals An adaptive thermal comfort model for naturally ventilated classrooms of technical institutions in Madurai

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Subhashini S. ◽  
Thirumaran Kesavaperumal ◽  
Masa Noguchi
Keyword(s):  
Thermal Comfort ◽  
Natural Ventilation ◽  
Higher Learning ◽  
Educational Institutions ◽  
Climatic Region ◽  
Content Type ◽  
Comfort Levels ◽  
Neutral Temperature ◽  
Adaptive Comfort ◽  
Temperature Levels

Purpose Occupants dwelling in hot climatic regions of India for a longer term are tolerable to high temperature levels than predicted by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards. The purpose of this study is to evaluate the thermal sensations (TS) and neutral temperature of the occupants in naturally ventilated (NV) and air-conditioned (AC) classrooms of two technical institutions located in the same premises in the suburbs of Madurai. The main focus of this study is to understand the occupants’ behaviour in response to the thermal conditions of the educational buildings particularly in the warm and humid climatic zone of Madurai. Design/methodology/approach This research collected data through field studies. The data included 383 survey questionnaires from NV classrooms and 285 from AC classrooms, as well as on-site measurements of interior and exterior weather conditions. The TS results show that the students preferred well-designed NV classrooms than AC classrooms. A new adaptive comfort equation derived from this study can be applied to NV classrooms in warm and humid climates where mean outdoor temperature exceeds 40°C. Findings The neutral temperature derived for NV classrooms in Madurai ranged from 29°C to 34°C. Thus, the occupants in the NV classrooms of the higher learning educational institutions in the warm and humid climatic region of Madurai can adapt well to higher indoor temperature levels than predicted by ASHRAE comfort levels with minimum adjustments. Research limitations/implications The study was limited to only occupants in two premier higher learning technical educational institutions located in Madurai region within 5–10 km within the city limits to understand the implications of microclimate with respect to the urban context. Thus, further research is required to examine the tendency under local conditions in other regions beyond those applied to this study. Social implications The findings of this study showed that occupants in higher learning educational intuitions in Madurai prefer NV classrooms than AC classrooms. Therefore, with rising demands of energy use for mechanical ventilation and the associated high cost for running AC buildings, architects should prioritize the design of energy efficient buildings through the optimal use of passive design strategies for ventilation and thermal comfort. This study gives a base data for architects to understand the adaptive limitations of occupants and design NV buildings that can promote natural ventilation and provide better thermal environments that can help increase the productivity of students. Originality/value This paper was an attempt to develop the adaptive comfort model for NV classrooms in Madurai regions. There has been no attempt to identify the adaptive comfort levels of occupants in higher learning technical educational institutions located in warm and humid climatic region of India.

scholarly journals Summertime Impact of Climate Change on Multi-Occupancy British Dwellings

2012 ◽  
Vol 37 (4) ◽  
pp. 50-60
Author(s):  
Shariful Shikder ◽  
Monjur Mourshed ◽  
Andrew Price
Keyword(s):  
Climate Change ◽  
Thermal Comfort ◽  
Threshold Temperature ◽  
Baseline Scenario ◽  
Adaptation Measures ◽  
User Adaptation ◽  
Human Thermal Comfort ◽  
Adaptive Thermal Comfort ◽  
Recent Climate ◽  
Adaptive Comfort

Recent climate change projections estimate that the average summertime temperature in the southern part of Great Britain may increase by up to 5.4°C by the end of the century. The general consensus is that projected increases in temperature will render British dwellings vulnerable to summer overheating and by the middle of this century it may become difficult to maintain a comfortable indoor environment, if adaptation measures are not well integrated in the design and operation of new dwellings, which are likely to remain in use beyond the 2050s. The challenge is to reduce overheating risks by integrating building and user adaptation measures, to avoid energy intensive mechanical cooling. Developing guidelines and updating building regulations for adaptation, therefore, requires an understanding of the baseline scenario; i.e. the performance of existing buildings in future climates. This paper aims to investigate the performance of new-build multi-occupancy British dwellings for human thermal comfort in the present-day and projected future climates in four regional cities: Birmingham, Edinburgh, London and Manchester. Evaluations are carried out by a series of dynamic thermal simulations using widely adopted threshold temperature for overheating, as well as adaptive thermal comfort standards. This study thus offers a unique perspective on regional variations of performance and provides a clearer snapshot because of the use of more appropriate adaptive comfort standards in the evaluations. Finally, the paper sheds light on possible personal and building adaptation measures to alleviate overheating risks.

scholarly journals The Strong Precipitation of the Dry Warm Front Cyclone in Syria and Its Prediction by Data Mining Modeling

Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1667
Author(s):  
Jianhong Wang ◽  
Nour Alakol ◽  
Xing Wang ◽  
Dongpo He ◽  
Kanike Raghavendra Kumar ◽  
...  
Keyword(s):  
Mediterranean Climate ◽  
Forecast Accuracy ◽  
Middle Layer ◽  
Forecast Model ◽  
Winter Precipitation ◽  
Reanalysis Data ◽  
The North ◽  
Warm Front ◽  
The Mediterranean ◽  
Upper Level

The Eastern inland of Syria has a Mediterranean climate in the north and a tropical desert climate in the south, which results in a dry south and wet north climate feature, especially in winter. The circulation dynamics analysis of 16 winter strong precipitation events shows that the key system is the dry and warm front cyclone. In most cases (81–100% of the 16 cases), the moisture content in the northern part of the cyclone is higher than that in the southern part (influenced by the Mediterranean climate zone). The humidity in the middle layer is higher than that near the surface (uplifting of the dry warm front), and the thickness of the wet layer and the vertical ascending layer obviously expands upward (as shown by the satellite cloud top reflection). These characteristics lead to the moisture thermodynamic instability in the eastern part of the cyclone (dry and warm air at low level and wet and cold air at upper level). The cyclone flow transports momentum to the local humid layer of the Mediterranean climate belt and then causes unstable conditions and strong rainfall. Considering the limitations of the Syrian ground station network, the NCEP/CFSR global reanalysis data and MODIS aqua-3 cloud parameter data are used to build a multi-source factor index of winter precipitation from 2002 to 2016. A decision tree prediction model is then established and the factors index is constructed into tree shapes by the nodes and branches through calculating rules of information entropy. The suitable tree shape models are adjusted and selected by an automated training and testing process. The forecast model can classify rainfall with a forecast accuracy of more than 90% for strong rainfall over 30 mm.

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