Search results for "Natural Ventilation"
showing 10 items of 21 documents
EVALUATION OF THE COMBINED EFFECT OF VEGETATION AND NATURAL VENTILATION IN NEARLY ZERO ENERGY MULTI-STOREY BUILDINGS – nZE(ms)B
2020
Cooling load is the main cause of high energy consumption for tall buildings in tropical climates while the construction of tall buildings is an unavoidable practice due to land scarcity in metropolitan cities. In this regard, the use of natural ventilation (NV) in tall buildings can help reducing the energy consumption. However, this solution can also bring the problem of polluted air that may enter the space to be ventilated. If the air is passed through a system that can absorb pollutants and add more oxygen to the air, the problem may almost be solved. Building integrated vegetation (BIV) systems can help solving this problem. So, if the air entering buildings passes through dense veget…
A Workflow for the Performance Based Design of Naturally Ventilated Tall Buildings Using a Genetic Algorithm (GA)
2019
Optimization of Natural Ventilation process in highrise buildings is one of the most complex and least addressed phenomenon in the field of sustainable architecture. This issue requires urgent consideration to reduce the computation time due to fast growing demand of vertical construction in metropolitan cities. Until recently most highrise buildings have been operated with mechanical systems, causing high energy loads in hot climates and have high carbon footprints. Highrise buildings with natural ventilation and sky gardens can address these problems. This study involves the development of a Genetic Algorithm (GA) addressing the multi objective optimization of natural ventilation in tall …
Ventilation rates and unsatisfied percentage from indoor CO2 concentration.
2011
This work reports the results of a survey carried out on a hall in a historic building in Palermo (Italy) with the aim of assessing the air quality by means of objective measurement of carbon dioxide (CO2) concentration and its subjective evaluation through a questionnaire. The measured values of CO2 concentration were compared with those evaluated using the Meckler equation under steady-state conditions, having verified necessary parameters such as the constancy of the indoor and outdoor CO2 levels and the uniformity of the CO2 generation rate for all the occupants. The positive correspondence between measured and calculated results allowed us to utilise, under differing circum- stances, t…
Computer model and simulation of a traditional passive cooling ventilation system in a Modern building in Mazara del Vallo (Italy)
2008
Traditional and modern natural ventilation techniques have been integrated in a hybrid system for a retrofitting of public building in the city of Mazara del Vallo (Italy). The hybrid ventilation and air cooling system integrates a wind tower, an indirect evaporative heat exchanger, a ground cooling pipe network and ventilated façade. The first idea was to design a passive cooling system inspired to the typical wind towers of the Middle East, being the area very well ventilated. On the other hand, air humidity in summer is quite high and therefore the effectiveness of indirect evaporative cooling is quite low. For this reason, it was adopted a second passive cooling system consisting in a g…
Experimental determination of natural air ventilation rates based on CO2 concentration
2009
This study reports the first results of a survey carried out by the authors on a hall used for conferences, training courses, seminars, and aimed to determine the correlation between the concentration of CO2 and the number of air changes only through natural ventilation. The assessment of ventilation rates was based on the knowledge of the indoor and outdoor CO2 concentrations and of the number of people in the hall. As it is known, the CO2 concentrations can be used as an index for the number of people present in a room and can be evaluated as a function of time by using the Meckler equation in steady-state conditions. In that case it is however necessary that some restrictive hypotheses a…
PASSIVE SYSTEMS FOR BUILDINGS INDOOR COMFORT
2016
The paper shows the preliminary studies for the University Campus ZEB Energy realization in Palermo. The particular location in the Mediterranean basin has required careful planning to resolve the problems related to high temperatures and humidity. For this reason has been employed strategies, elements and building materials that meet the requirements of sustainability and energy savings provided by law, in order to build a new building energy self-sufficient. The University of Palermo had the need to create new spaces to be used as classrooms for different types of education and especially of a space for conferences and conventions. This type of spaces is usually very energy eater because …
Evaluation of the Thermodynamic Performance of the Traditional Passive Systems
2011
The need to reduce urban consumption of energy in the buildings, one of the major energy waster resulting in emission of CO2, is pushing research in the field of building design to the appreciation of passive air-conditioning systems that can be integrated with conventional systems and determine, therefore, the so-called hybrid systems. Historically this passive systems were developed in the Mediterranean and in the Middle East area. Actually the research activity has been focused on this problem, through an approach that involves the application of design strategies and the development of computational tools and control systems. The synergy between current scientific knowledge, advanced ma…
Review of wind tunnel modelling of flow and pollutant dispersion within and from naturally ventilated livestock buildings
2021
[EN] Ammonia emissions from naturally ventilated livestock buildings (NVLBs) pose a serious environmental problem. However, the mechanisms that control these emissions are still not fully understood. One promising method for understanding these mechanisms is physical modelling in wind tunnels. This paper reviews studies that have used this method to investigate flow or pollutant dispersion within or from NVLBs. The review indicates the importance of wind tunnels for understanding the flow and pollutant dispersion processes within and from NVLBs. However, most studies have investigated the flow, while only few studies have focused on pollutant dispersion. Furthermore, only few studies have s…
Natural ventilative cooling in school buildings in Sicily
2016
The paper shows analysis of the impact on thermal comfort of natural ventilation in a nonresidential Mediterranean case-study. Results are based on the EN 15251 approach on adaptive comfort. Different scenarios are proposed, granting an improvement of up to 10% in the number of summer comfort hours.
Soluzioni per la ventilazione naturale e precetti igienici nell’edilizia ospedaliera tra Ottocento e Novecento
2016
La ventilazione, il riscaldamento e raffrescamento, il soleggiamento divennero, tra Ottocento e Novecento, strumenti imprescindibili per garantire la salubrità dell’aria e degli ambienti, sia nel caso di risanamento di edifici esistenti, sia nella realizzazione di nuove costruzioni. La tipologia degli ospedali era, al pari delle scuole, teatri, mercati quella in cui i sistemi di ventilazione finalizzati all’igiene dell’aria erano studiati con più accuratezza. Si ricorreva ad ingegnosi espedienti che consentivano di mantenere nello stabilimento sanitario quelle condizioni che garantissero il comfort ambientale, evitando l’entrata di aria dai padiglioni delle malattie infettive; particolare i…