Air Wind Research Articles

Оценка деформации зоны распределения жидкого противогололедного реагента при различных параметрах внешней среды

The article considers distribution of liquid deicing reagents over aerodrome pavement. The deformation of the treatment zone contributing to the formation of unevenness of distribution under different environmental parameters (air temperature, wind speed and direction) is estimated. The research is based on the developed mathematical models of the reagent droplet movements over the distribution disk and in the air. The dependence of overlapping the two zones and the width of the untreated zone on the wind speed and direction is derived. The process of reagent distribution at different ambient temperatures and varying height of disks above the pavement is simulated. Estimation of quality indicators of anti-icing treatment for the temperature range from 0 to --15 °C is given on the basis of the obtained results. The practical value of the obtained results lies in the possibility of their application in the development of operational methods to ensure the quality of distribution of liquid chemicals under changing environmental conditions.

Climatic Comfort Potentials in the View of Tourism in Ilam Province Using Equivalent Temperature Index (ETI) and Discomfort Index (DI)

The purpose of present research is to assess Ilam provincial climate in the view of tourism using Equivalent Temperature Index Discomfort Index. In this regard, it was used dataset of National Meteorology Organization and statistics of General planning and management Department, Ilam provincial stations (& stations) from the date of their opening to the end of 2016. Then, collected data were considered by two respective indices. Discomfort Index will calculate the rate of human discomfort in relation to thermal factor using air temperature, relative humidity (RH) and wind rate. Equivalent Temperature Index will assess common effects of temperature on living organism in relation to air temperature and evaporation. Results obtained from Ilam provincial tourism climate by means of Equivalent Temperature Index showed that the lowest and highest annual scores were related to Ilam and Dehloran cities, respectively. Results of Discomfort Index (DI) showed that the lowest and highest DI scores related to Ilam city in January and Dehloran city in July were 614 and 28.8, respectively. Based on obtained results, Ilam province had two different spatial and temporal spans for tourism. Tow that, in regard to tourist attraction, if northern region has optimal conditions in one season, at the same time, there is no optimal conditions in southern regions.

Case study: Analysis of the propagation of noise generated by construction equipment

In the construction industry, workers are exposed to several risks, among them is the noise generated by construction equipment. This research had as its objective to evaluate the noise emitted by circular saws and concrete mixers, equipments usually present on construction sites, in order to propose noise control measures. For that purpose, the propagation curves (isoclines) of the sound pressure level (SPL) were measured and analyzed during the operation of three concrete mixers and three circular saws. The sound measurements were conductedwith the type 2 sound level meter, while for air temperature and wind speed a digital thermo-anemometer was used. Contour lines representing the isoclines of SPL were generated, and control measures were proposed. The results show that values of SPL above 85 dB(A) were observed at a maximal distance of 7 m from the source for concrete mixers and 16 m for circular saws. It was also confirmed that the furthest distance that the SPL is greater than 85 dB(A) depends on the number of barriers, screens and masonry walls. In obstacle-free areas, the rate of reduction of sound intensity was 1.26 dB(A) per meter for concrete mixers and 1.47 dB(A) per meter for circular saws. The SPL isoclines should be considered in planning of construction sites and organizing adequate control measures.

Effect of Street Morphology on Buildings’ Thermal Storage in a Hot and Arid Climate: Case Study of Biskra (Algeria)

This work is an experimental study focusing on the relationship between street morphology and thermal storage in buildings. The first aim of this study is to reduce air conditioning usage in hot and arid areas, taking as example Biskra city (Algeria), during the long summer period (5 months), by reducing thermal storage. This leads to the reduction of carbon emissions to a level higher than the individual construction level in order to design a sustainable city, using measuring instruments (kimo HD 100 and Cason CA 380), we measured outdoor air temperature, wall temperature, relative humidity and wind speed on three street morphologies ; the (canyon, dihedral and open streets). These streets are different in terms of morphological indicators such as Sky View Factor (SVF) and albedo materials (a). We also applied mathematical equations across the thermal balance to calculate thermal storage. Our second goal was to identify the morphological indicators of the streets affecting the thermal storage of buildings. In this context, the obtained results showed that SVF was the most influential parameter on the heat storage.

Assessing exposure to unconventional natural gas development: using an air pollution dispersal screening model to predict new-onset respiratory symptoms

Various exposure estimates have been used to assess health impact of unconventional natural gas development (UNGD). The purpose of this study was to (1) use an air pollution dispersal screening model and wind direction to characterize the air emissions from UNGD facilities at each residence and (2) assess association of this exposure estimate with respiratory symptoms. Respiratory symptoms were abstracted from health records of a convenience sample of 104 adults from one county in southwestern PA who had completed a standard clinical interview with a nurse practitioner. Using publicly available air emission data, we applied a “box” air pollution dispersion screening model to estimate the median ambient air level of CO, NOx, PM 2.5, VOCs, and formaldehyde at the residence during the year health symptoms were reported. Sources and median emissions were categorized as north, south, east, or west of the residence to account for the effect of wind direction on dispersion. Binary logistic regression was performed for each respiratory symptom. Number of sources had varying magnitudes of association with some symptoms (i.e., cough, shortness of breath, and “any respiratory symptom”) and no association with others (i.e., sore throat, sinus problems, wheezing). Air emissions were not associated with any symptom.

Investigation and low energy improvement of the thermal environment of work areas in the Qingdao Metro in winter

Few studies have investigated the thermal environment of the work area hall in underground metro stations during winter. Two underground stations were chosen within Qingdao Metro Lines 2 and 3 to investigate the thermal environment in the work area hall in northern city metros in China. Air temperatures and wind velocity parameters were identified as key influencing factors and were continuously measured in the work area. The study found that the thermal environment fluctuates frequently in the work area throughout the day. Changes in temperatures and wind speeds were periodically caused by piston wind flowing from the platform level. To improve this heating situation in the work area in winter, the study proposes recycling waste heat from the power equipment rooms, using the air source but through the water cycle heat pump system. Insights from the study may help save energy and improve the thermal environment, and could be applied across metro stations in north China cities in winter. Practical application: The thermal comfort of the working area in the metro station hall is extremely poor as indicated by a study of Qingdao Metro stations. This paper explores the application of a heat pump as a means of heating the working area to improve the cold and damp winter environment for the metro staff using waste heat from the machine rooms.

Urban weather modeling applications: A Vienna case study

Recently, the interest in urban weather modeling methods has been steadily increasing. This is in part due to the insight that thermal building performance simulations are typically undertaken with standardized weather files that provide a rather general perspective on urban weather conditions. This may lead toward errors in conclusions drawn from modeling efforts. In this context, present contribution reports on the potential of different approaches to generate location-dependent urban meteorological data. We compare the meteorological output generated with the Weather Research and Forecasting (WRF) model, Urban Weather Generator, and morphing approach. These methods were compared based on empirical data (air temperature, humidity, and wind speed) collected from two distinct urban locations in Vienna, Austria, over 5 study periods. Our results suggest significant temporal and spatial discrepancies in resulting modeling output. Results further suggest better predictive performance in the case of high-density urban areas and under warmer and extreme conditions in spring and summer periods, respectively.

<p class="HeadingRunIn"><strong>Population Dynamics and Seasonal Occurrence of Adult <em>Amphipsyche meridiana</em> Ulmer 1902 (Trichoptera: Hydropsychidae) in an Irrigation Pond Outlet</strong></p>

Population dynamics and seasonal occurrence of adult Amphipsyche meridiana Ulmer, 1902 (Trichoptera: Hydropsychidae) in an irrigation pond outlet at Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom Province were determined, with the influence of air temperature, wind speed, precipitation and relative humidity on its population density being evaluated. Samples were collected monthly from January to December 2013 by light trapping. Monthly sampling records for adults collected were 24876, 2605, 29344, 43632, 18684, 16524, 29871, 15183, 10548, 17100, 7695 and 15678, respectively. An increase in the number of adults collected was observed from January to July with peaks of 43,632 (18.83%) in April. A remarkable decrease in the number of insects collected was observed in the months after August. There was an increase in the number of adults most influenced by the decrease in precipitation and relative humidity.

Severity of the present-day climate in the Polar regions of Siberia

Over the period 1981–2015 severe climatic conditions on the North of Siberia (area within 66–162° E above the Polar Circle) were characterized by significant space-time variations of air temperature at the cold period of the year. This conclusion is made on the basis of analysis of observations made about 13 hour of local time. Positive changes in the mean seasonal air temperature were observed here in October–April. The largest rates of air temperature rise with a pronounced gradient to the West were noted in high latitudes, i.e. in Arctic glacial and polar desert landscapes. The change in weather severity which is one of characteristics of the climate discomfort was analyzed by means of the Arnoldi index (TA). This index reflects the combined effect of negative temperatures and stiff wind on the thermal state of the open surface of the human body. Together with the space-time dynamics of the actual TA values, important values of TA are its threshold values (more than 30 and more than 45 units) which determine a degree of discomfort. Duration of these periods, limiting a possibility of a person's stay in the open air, is also extremely important as well. In recent decades (1981–2015), the spatial differentiation of the number of days (from 80 to 160) limiting the human’s stay in the open air reflects in the main fluctuations of the air temperature and wind regime in polar landscapes. Slight warming (a rise of the air temperature) and small wind speed variability during the period from October to April in 1981–2015 resulted in a certain decrease in the index of weather severity in relation to the period 1966–1980, since the last one did not did not go beyond limit of the interannual variability. Despite the stable increase in the air temperature in 1981–2015, no tendency to reduction of the number of days limiting human’s stay in the open air was noted. The duration of this period for 1981–2015 is similar to that observed in 1936–1964, and we believe that this is suggestive of manifestation of the cyclicity of atmospheric processes and is agreed with a gradual decrease in the rate of the temperature rise. In the last period duration of the period limiting human stay in the open air in the considered area remains high and ranges from 3.5 (to the west of 80° E) to 5 months on islands and capes of the region. So, as is demonstrated by the above example of space-time dynamics of the weather severity index at the time about 13 hours of local time, no decrease in the level of discomfort in polar Siberia is found.

Presence of Buildings and their Influence on Patterns of Urban Microclimates, a Case Study in the City of Juiz de Fora, Southeast Brazil

Several mechanisms and processes are responsible for the urban climate. A city’s growth intensity and speed along with the distinct and complex materials of which it is composed, lead to multiple urban microclimates. The main objective of this research was analysing the influence of one of these factors – the buildings – in an area near the central zone of Juiz the Fora, a city in Brazil, and the patterns of microclimates associated with them. The presence of buildings might be creating thermal and barometrical distinct fields, influencing the population’s quality of life. Five sampling points spatially distributed in previously designated locations were chosen. Meteorological stations collected air temperature, wind and air humidity data at each sampling point. Maps were made for the purpose of observing the spatial distribution patterns of the buildings, comparing the geographical location of the Points, number of pavements and 3D Shadows. The buildings had a significant effect on patterns of microclimates. A wind corridor was also found at point 2, as a result of the dimensions and disposition of the access roads and their buildings. There is a need to rethink planning laws related to the urban land use and cover of the city of Juiz de Fora, taking into consideration the effect of buildings as part of the planning process.

Understanding Environmental Changes Using Statistical Mechanics

We present results for Shannon entropy from environmental data, such as air temperature, relative humidity, rainfall and wind speed. We use hourly generated time-series hydrological model data covering the whole of Tasmania, a state of Australia, and employ concepts from statistical mechanics in our calculations. We also present enthalpy and heat capacitance equivalent quantities for the environment. The results capture interesting seasonal fluctuations in environmental parameters over time. Our results also present an indication that corresponds to a slight increase in the number of microstates due to air temperature over the duration of data considered in this work.

Characteristics of Horizontal Precipitation in Semi-Humid Forestland in Northern China

Little information is available on horizontal precipitation in forest land in semi-humid climate regions. In this study, the quantity and duration of horizontal precipitation were investigated using the high precision weighing lysimeter system in the mountainous areas of northern China during the experiment year 2011 and 2012. The purpose of this study was to better understand the formation mechanisms of horizontal precipitation in the semi-humid climate region. The results showed that hourly values of horizontal precipitation distributed between 0 and 0.1 mm, and that the one-night values distributed between 0.2 and 0.4 mm. The number of days with horizontal precipitation accounted for about 45% of the whole year. The average monthly amount of horizontal precipitation was 4.5 mm in the non-growing season, while it was a mere 1.6 mm in the growing season. The total amount of horizontal precipitation in the year was about 33 mm. Horizontal precipitation represented about 4.61% and 4.23% of the annual precipitation in 2011 and 2012. During the non-growing season, water vapor absorbed by the soil was greater than canopy and soil condensation, not only in terms of frequency, but also in the cumulated quantity. On a typical day, the canopy and soil condensation was 0.07 mm, accounting for 31.81% of total quantity of horizontal precipitation (0.22 mm). Air temperature, soil temperature and wind speed were negatively correlated with the quantity and duration of horizontal precipitation. This research could provide information for a better understanding of the ecological significance of horizontal precipitation in the semi-humid climate region in northern China.

Assessment the Effect of Nanofluid on Turbulent Heat Transfer and Pressure Drop in Bend Finned Tube

An experimental study of using Al2O3-water nanofluid that flows in a finned bend tube cross flow heat exchanger on heat transfer and pressure drop was implemented. The experimental part consists of closed loop of water or nanofluid that flows in the bend tube heat exchanger that inserted in an air wind tunnel. The effect of different nanoparticles volume fraction of (0, 0.01, 0.05, 0.1 and 0.2%Vol.) were depressed in deionized water. The hot water or nanofluid flow in the two types of smooth and finned bend tube heat exchanger with different inlet Reynolds numbers for the range of (450-920) for laminar flow and (6900-10000) for turbulent flow. The experimental results were presented as a friction factor, local and average Nusselt number for the water and air side respectively for the smooth and finned bend tubes. The results show that the inner average Nusselt number of Al2O3-water nanofluid that flows in heat exchanger enhanced by up (34.6 %) for smooth tube heat exchanger and about (44.1 %) for finned bend tube heat exchanger compared to pure water. Also, the friction factor of the nanofluid flow inside the heat exchanger increase by up (13.9 %) for smooth bend tube heat exchanger and (22%) for finned bend tube as compared with the use of pure water.

Neuro-fuzzy systems to estimate reference evapotranspiration

Routine and rapid estimation of evapotranspiration (ET) at regional scale is of great significance for agricultural, hydrological and climatic studies. A large number of empirical or semi-empirical equations have been developed for assessing ET from meteorological data. The FAO-56 PM is one of the most important methods used to estimate evapotranspiration. The advantage of FAO-56 PM is a physically based method that requires a large number of climatic parameter data. In this paper, the potential of two types of neuro-fuzzy system, including ANFIS based on subtractive clustering (S_ANFIS), ANFIS based on the fuzzy C-means clustering method (F_ANFIS), and multiple linear regression (MLR), were used in modelling daily evapotranspiration (ET0). For this purpose various daily climate data – air temperature (T), relative humidity (RH), wind speed (U) and insolation duration (ID) – from Dar El Beidain Algiers, Algeria, were used as inputs for the ANFIS and MLR models to estimate the ET0 obtained by FAO-56 based on the Penman-Monteith equation. The obtained results show that the performances of S_ANFIS model yield superior to those of F_ANFIS and MLR models. It can be judged from results of the Nash-Sutcliffe efficiency coefficient (EC) where S_ANFIS (EC = 94.01%) model can improve the performances of F_ANFIS (EC = 93.00%) and MLR (EC = 92.12%) during the test period, respectively.

Polynomial chaos expansion and response surface method for nonlinear modelling of reference evapotranspiration

ABSTRACTThe feasibility of polynomial chaos expansion (PCE) and response surface method (RSM) models is investigated for modelling reference evapotranspiration (ET0). The modelling results of the proposed models are validated against the M5 model tree and multi-layer perceptron neural network (MLPNN) methods. Two meteorological stations, Isparta and Antalya, in the Mediterranean region of Turkey, are inspected. Various input combinations of daily air temperature, solar radiation, wind speed and relative humidity are constructed as input attributes for the ET0. Generally, the modelling accuracy is increased by increasing the number of inputs. Including wind speed in the model inputs considerably increases their accuracy in modelling ET0. Mean absolute error (MAE), root mean square error (RMSE), agreement index (d) and Nash-Sutcliffe efficiency (NSE) are used as comparison criteria. The PCE is the most accurate model in estimating daily ET0, giving the lowest MAE (0.036 and 0.037 mm) and RMSE (0.047 and 0.050 mm) and the highest d (0.9998 and 0.9999) and NSE (0.9992 and 0.9996) with the four-input PCE models for Isparta and Antalya, respectively.

Differences between times of day for the basic physiological traits of Nellore bulls exposed to solar radiation

ABSTRACT The aim of this study was to evaluate the basic physiological traits of Nellore bulls exposed to solar radiation at different times of the day. Sixteen Nellore bulls with an average age of 3 years were used. Air temperature (Ta, °C), relative humidity (RH, %), wind speed (U, m/s) and solar radiation (Rs, W/m2) were the meteorological variables evaluated during the study. Respiratory rate (Fr, breaths/min), rectal temperature (Tr, °C), body surface temperature (Ts, °C) and expired air temperature (Texp, °C) were evaluated as physiological traits. The highest Fr and Ts averages were observed from 11:00 to 14:00 (36.34 breaths/min and 37.62 °C, respectively). Texp presented increasing values throughout the day, with its highest average (33.35 °C) between 15:00 and 17:00. The Tr did not present significant variation between the times of day. It is concluded that intense Rs and high Ta during the hottest times of day induce Nellore bulls to trigger thermoregulatory mechanisms, such as the respiratory system, to maintain body temperature within narrow limits.

A meta-analysis over geometric modeling simplifications in ENVI-met urban climate simulation

Abstract Environmental modelling requires, among other aspects, a description of the built geometry. However, the complexity of the urban tissue draws uncertainties about the building form and locations. Therefore, during the planning process generic simplified geometry models may be more appropriate than the detailed ones. This research shows a meta-analysis performed by comparing the results of detailed and simplified geometric models. The prediction deviations that may arise from using geometric simplifications on ENVI-met modelling were evaluated, considering the output data from different building typologies (one and ten-storey buildings) and urban scenarios (with and without internal squares). Three metrics were analysed: air temperature, wind speed, and sky view factor (SVF). These metrics were normalized between 0 and 1 for comparison and performance assessment. The results indicated that the most adequate simplification models are those that that have kept the building perimeter of the blocks unchanged in relation to the corresponding detailed models.

Comparative analysis of indoor and outdoor concentration of PM10 particulate matter on example of Cracow City Center

Article concerns the problems of air pollution with PM10 particulate matter in Cracow. An indoor concentration of PM10, along with the outside air pollution, was observed in the period between January and March. Comparative analysis was carried out, especially for the periods with exceptionally high outside concentration of PM10. Both outside and inside concentration results were subjected to analyses on raw and averaged (minute, hourly, daily) data, along with extreme values. The results of investigations showed that for the time periods with extremely high concentration of particulate matter suspended in the air outside, the air quality indoor was also poor. In general, after exceeding the value 250 μg/m3, PM10 concentration inside building was higher than outside, especially during night time. Analysis of the relationship between PM10 concentration and air temperature and wind speed showed higher correlation between PM10 and wind speed; however, the relationship PM10–temperature appeared significant, too.

Neural networks in climate spatialization and their application in the agricultural zoning of climate risk for sunflower in different sowing dates

ABSTRACTSunflower is a species that is sensitive to local climate conditions. However, studies that use artificial neural networks (ANNs) to evaluate this influence and create tools such as agricultural zoning of climate risk (ZARC) have not been conducted for this species. Due to the importance of sunflower as a human food source and for biodiesel production, and also the necessity of conducting research to evaluate the suitability of this oleaginous species under different climatic conditions. Thus, we seek to construct a ZARC for sunflower in Brazil simulating sowing on different dates and using meteorological elements spatialized by ANNs. Climate data were used: air temperature (T), rainfall (P), relative air humidity (UR), solar radiation (MJ_m−2_d−1) and wind velocity (U2). Climatic regions considered suitable for the cultivation of sunflower had average annual values for T between 20 and 28°C, P between 500 and 1.500 mm per cycle, and soil water deficit (DEF) below 140 mm per cycle. A neural network is an efficient tool that can be used in spatialization of climate variables quickly and accurately. Sunflower sowing in the spring and summer are the ones that provide the largest suitable areas in southeastern Brazil, with 58.13 and 64.36% of suitable areas, respectively.

Spatially distributed water-balance and meteorological data from the Wolverton catchment, Sequoia National Park, California

Abstract. Accurate water-balance measurements in the seasonal, snow-dominated Sierra Nevada are important for forest and downstream water management. However, few sites in the southern Sierra offer detailed records of the spatial and temporal patterns of snowpack and soil-water storage and the fluxes affecting them, i.e., precipitation as rain and snow, snowmelt, evapotranspiration, and runoff. To explore these stores and fluxes we instrumented the Wolverton basin (2180–2750 m) in Sequoia National Park with distributed, continuous sensors. This 2006–2016 record of snow depth, soil moisture and soil temperature, and meteorological data quantifies the hydrologic inputs and storage in a mostly undeveloped catchment. Clustered sensors record lateral differences with regards to aspect and canopy cover at approximately 2250 and 2625 m in elevation, where two meteorological stations are installed. Meteorological stations record air temperature, relative humidity, radiation, precipitation, wind speed and direction, and snow depth. Data are available at hourly intervals by water year (1 October–30 September) in non-proprietary formats from online data repositories (https://doi.org/10.6071/M3S94T).