A. Galesi

A proposed methodology for estimating the performance of small wind turbines in urban areas

Large and medium scale wind turbine systems represent feasible renewable resources of energy, that constitute an alternative to conventional energy supply systems. However the development of small-scale wind turbines is still uncertain due to the difficulty in their use especially in urban areas.

Thermal Comfort In Operating Rooms:A Case Study

This paper focuses on thermal comfort in hospital operating rooms (ORs). Thermal comfort depends on several factors such as temperature conditions of the operating room, insulation of protective clothing, stress, rate of metabolism and safety mechanisms in the body to keep core temperature stable. The modification of any of these elements triggers defense mechanisms which in extreme cases may lead to serious disturbances in the body. The maintenance of recommended standards (ISO 7330) concerning thermal conditions in operating rooms ensures the highest possible physical capabilities of the personnel while providing maximum safety for the patients. The purpose of the present work is to report the results obtained during an experimental campaign carried out at the Umberto I Hospital in Enna in order to improve efficiency of HVAC installations to secure thermal comfort in the operating rooms.

Thermal comfort analysis of public transport passengers in Catania

The issue of passenger comfort on board public transport is gaining increasing importance in the last few years. Thermal comfort and indoor air quality are often a problem for the passengers during transportation. This paper presents the results of measurements and thermal comfort analysis and indoor air quality to which passengers are exposed during the utilization of public transport of Catania city. To individuate the thermal comfort of passengers the following indices are used: gradient of temperature, PMV, RWI, CO2 and CO concentration, SSI and Humidex.

Energy Analysis of Ventilated Roof

The thermal performance of the building envelope is an important requirement for guaranteeing both a comfortable indoor climate and building’s energy efficiency.

Analysis of acoustic climate on board public transport

The issue of thermal and acoustic comfort of passengers on board public transport has not yet been suitably faced in recent years. High-ranking of noise and improper thermal climate inside buses, trams and tubes can provoke justifiable complaints of passengers and noise impact. Noise impact may impair safety when it hinders communication inside the vehicles, causing fatigue, loss of concentration and is, obviously, annoying too. The research has been subdivided into two steps: the first is about thermal comfort and the second step has been drawn to evaluate by experimental measurements the main parameters characterizing the acoustic comfort: Equivalent sound pressure Level (Leq), Noise Rating (NR) and Speech Interference Level (SIL). All these parameters can give useful indications about the comfort status of passengers. Analysis and elaborations of measured data were taken to discover that passengers are often exposed to high levels of noise, which causes stress especially for older people and children.

A Neural Network model for the estimation of bioclimatic indexes

Many researches have highlighted the influence of climate on mortality, showing a high increase in mortality in the summer time during “heat waves”, periods of very high temperature and humidity levels. The bioclimatic indexes are used in urban climate studies to describe the level of thermal sensation that a person experiences due to the modified climatic conditions of an urban area. The index provides a meaningful and realistic indicator that can not only be used as an information as to how hot it feels, but also as a readily identifiable warning for individuals subject to the physiological dangers of heat exposure. The authors have developed a methodology that, by means of the Neural Network (NN), permits one to predict the values of meteorological data and then the calculation of the bioclimatic indexes. The meteorological data required for the calculation of the bioclimatic index concerning hourly values of air temperature, relative humidity, wind speed have been used according to the records of the meteorological station of the Pergusa Lake (EN), for the year from 2003 to 2006 NN-estimated, the bioclimatic indexes values were compared with coincident bioclimatic indexes values obtained from air temperature and relative humidity observations recorded at standard meteorological stations. Statistical analysis showed a good agreement between the NN-estimated and the station-observed bioclimatic indexes values, with a root mean square error (RMSE) < 1%.

Air Quality In Street Canyons: A Case Study

Keeping the air quality acceptable has become an important task for decision makers as well as for non-governmental organizations. Particulate and gaseous emissions of pollutants from auto-exhausts are responsible for rising discomfort, increasing airway diseases, decreasing productivity and the deterioration of artistic and cultural patrimony in urban centers. Air quality limit values, which are aimed at protecting public health, are frequently exceeded especially in streets and other urban hotspots. Within these streets, pedestrians, cyclists, drivers and residents are likely to be exposed to pollutant concentrations exceeding current air quality standards. In order to give the right support to decision makers for air pollution control, a suitable microscale dispersion model must be used to investigate phenomenon The paper presents the results obtained by utilizing a three dimensional numerical model based on Reynolds-averaged Navier–Stokes equations to simulate the fluid-flow development and pollutant dispersion within an isolated street canyon. Finally, the authors tested the reliability of the same code examined resemblances and differences between the measured data coming from a survey measurement within the canyon and the data coming from the code.

An applied research to forecast the trend of air pollution in particular geometries of streets: the real case of urban canyon

High pollution levels have often been observed in urban street canyons due to the increased traffic emissions and reduced natural ventilation. To investigate this phenomenon suitable microscale dispersion models must be used in order to give the right support to decision makers for air pollution control. Within these streets, pedestrians, cyclists, drivers and residents are likely to be exposed to pollutant concentrations exceeding current air quality standards. In this way people carried out an applied research choosing the “V. Giuffrida” street of Catania as a test canyon because this street shows both geometric features typical of an urban canyon and a lot of car traffic flowing during all the day. In the first step the authors carried out preliminary and suitable studies about street and surrounding buildings geometries, meteoclimatic local data, intensity of traffic flow in different hours of day and so on. In the second step a computational model of the street canyon has been developed taking into account all blocks of buildings on each side of the street according to the actual urban situation. The computational model has been done using K–e turbulence model and under three wind directions and velocity values characteristic of the area. Finally, people carried out a campaign of concentrations measurements of tracer gas on suitable sections of the investigated street. This paper intends to show: the methodologies and techniques to draw the investigation with the backing of a 3D computer code suitable for this use (Airpak – Fluent in our case). the particular flow-dynamic situations with formation of pollutant store zones. the influence of both buildings geometry and the presence of internal courtyard on pollution profiles. The distribution of gas concentrations along the facades of buildings flanking the street with reference to those zones which, overcoming the alarm limits of law, can cause detrimental effects on the health of the inhabitants.

AN APPLIED TEST TO EVALUATE THE USE OF FLUID DYNAMIC CODE AS A PREDICTIVE KEY OF AIR POLLUTION FROM URBAN ROAD TRAFFIC

Urban air pollution is a direct function of the consistency of flows of motor vehicles traveling through each zone of a city, of the geometry of structures at the boundary of streets where conditions effect the dispersive fluid dynamics of exhaust gases, and, of course, of meteoclimatic features of various zones that form the entire urban area. While urban planners actually consider the sole possibility of increasing the average speed of the run of traffic flow, they do not consider the health hazard for city dwellers that may be caused by the Plan of Urban Traffic (PUT) regarding air pollution from exhaust pipes, especially in a supersaturated urban area. To achieve a good PUT, both the solution of traffic problems and the control of health hazards caused by air pollution must be taken into account. To this aim, this paper gives selected results achieved by application and testing of MIKSAM fluid dynamic code used as the key to forecasting concentrations of polluting gases in a large area of Catania (Italy) marked by high flows of motor vehicles throughout the day. The knowledge of forecasted air pollution, zone by zone, could guide planners to the best choices to achieve both goals: increasing average speed and avoiding health hazards.

The Increase Of Carbon Dioxide In The Atmosphere And Its Possible Negative Effects On The Biosphere And Mankind

Some scientists of “Anthropogenic Global Warming” (AGW), such as M. T. Boy Koff, A. M. McCright et al., claim that the increase in atmosphere of greenhouse gas carbon dioxide (CO2) coming from anthropogenic burning fossil fuels will cause a rising of air temperature that, in a few decades, will create severe uncountable problems for mankind and the biosphere. On the contrary, other scientists who support the thesis of “Not Anthropogenic Global Warming” (NAGW), the so-called “skeptics”, such as L. Weinstain, N. Scafetta et al., affirm that the increase of CO2 coming from the various human activities will not be able to increase air temperature in the atmosphere in such a way as to cause dangerous consequences for the biosphere. For “skeptics” the rising of temperature in the atmosphere is caused mainly by a natural mechanism of the planetary system and other natural causes not strictly connected with anthropogenic activities. Moreover, they rely on theories based on the thermodynamic and physicalchemical equilibrium on the Earth’s atmosphere and based on the variation of both CO2 concentration and air temperatures down the ages. The aim of this paper is to demonstrate that both AGW and “skeptics” scientists, when analyzing the different problems caused to mankind and the biosphere were referring to only one of the two sides of the same medal. Based on this concept, the paper investigates: uf0b7 the changes on the increase of CO2 in the Earth’s atmosphere both in a human and in a geological scale of time; uf0b7 the most convincing theories that justify the “skeptics’” statements; uf0b7 the negative effects of rising CO2 concentration in the human scale of time.