Tag Archives: solar radiation

1614-1621 D.V. Cao and P. Kic
Analysis of indoor temperature in the workshop building during the summer: a pilot study
Abstract |
Full text PDF (580 kB)

Analysis of indoor temperature in the workshop building during the summer: a pilot study

D.V. Cao* and P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamýcká 129, CZ165 21, Czech Republic
*Correspondence: caodoan2006@gmail.com

Abstract:

The aim of this paper is the presentation of measurements’ results and the calculation
method for analysis and evaluation of climate conditions as well for using of natural illuminance
in two large simple buildings during summer which could be used to calculate power demand for
the air cooling to reduce the indoor temperature caused by solar radiation. In this research, we
carried out experiments of measuring the indoor temperature at level of working place which is
1.1 m, in two similar large workshops with floor area 260 m2 and height 6.5 m, during several
hot summer days. The indoor conditions were strongly influenced by the solar radiation as the
buildings have large wall and roof windows. The indoor air temperatures in the first building
achieved 39.5 °C, which caused the heat stress for workers. The indoor air temperatures in the
second building achieved only 29.5 °C. The calculated power demand for the air cooling to reduce
the indoor temperature to 25 °C is 25.6 kW in the first building, the cooling power for second
building is 14.9 kW. We investigated measured construction of the workshop and we set up the
formula in order to calculate thermal balance. The measurement results and calculated results in
two buildings are compared and summarized in the tables and in the graphs for analysis. As a
general conclusion, it must be said that solar radiation has a big influence on the air temperature
and methods of passive air-conditioning should be more applied also on the production buildings
in industry, agriculture and other branches of civil engineering to release heat increasing air
temperature inside the building.

Key words:

, , ,




910-916 A. Stunda-Zujeva, M. Zuteris and K. Rugele
Sunlight potential for microalgae cultivation in the mid-latitude region – the Baltic states
Abstract |
Full text PDF (824 kB)

Sunlight potential for microalgae cultivation in the mid-latitude region – the Baltic states

A. Stunda-Zujeva*, M. Zuteris and K. Rugele

Riga Technical University, Faculty of Materials Science and Applied Chemistry, Institute of General Chemical Engineering, Pulka 3, LV-1007 Riga, Latvia
*Correspondence: agnese.stunda-zujeva@rtu.lv

Abstract:

Products, e.g. food and feed from microalgae are a promising part of bioeconomy. One of the most investigated and highly demanded microalgae is Spirulina. Light is one of limiting factors for biomass cultivation by photosynthesis. Sunlight is cheap and climate friendly light source. The aim of this study was to evaluate available sunlight potential in the mid-latitude region – the Baltic states (Europe, 55–60 °N) for microalgae, e.g. Spirulina growth. The data of Climate atlas based on satellites of EUMETSAT and data from an observation station in Riga were analyzed. The latitude and climate (cloudiness) were main parameters affecting the total solar radiation received by Earth’s surface. The sunlight potential in the Baltic states was higher than in most of Europe in similar latitude. Multi-year mean daylight intensity in the Baltic states was slightly less than in Southern France or Bulgaria, (26 klux and 30 klux, respectively, in summer) where Spirulina is commercially produced. Hourly solar radiation varied a lot in the Baltic states – from 880 W m-2 to 200 W m-2, sunny and overcasted noon of summer day, respectively; average value (8 a.m.–4p.m.) was 450 W m-2. Summer days are longer than 12 h, reaching 18 h in midsummer. The sunlight potential is suitable for microalgae, e.g. Spirulina cultivation in this period. From November till February days are shorter than 10 h and solar radiation is less than 300 W m-2 even in noon of sunny days.

Key words:

, , , , ,




426–434 P. Kic
Effect of construction shape and materials on indoor microclimatic conditions inside the cowsheds in dairy farms
Abstract |
Full text PDF (347 kB)

Effect of construction shape and materials on indoor microclimatic conditions inside the cowsheds in dairy farms

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 21 Prague, Czech Republic
E-mail: kic@tf.czu.cz

Abstract:

The aim of this paper is to present the results of microclimatic research focused on the indoor conditions in cowsheds and milking parlours in two dairy farms. The attention is paid mainly to the construction and materials used for buildings, which can influence together with technological equipment and system of ventilation the microclimatic conditions inside the cowsheds. In the frame of this research main parameters of internal and external properties of climate (air temperature, humidity, globe temperature, THI, BGHI and concentration of CO2) during the hot summer were measured and evaluated. Results of long time and short time measurements show very important role of used materials and shape of buildings. The research results show that the use of principles of passive air conditioning can contribute significantly to the improvement of internal microclimate. Reduced amplitude of temperature oscillation was 42.4% of amplitude of outside air temperature in cowshed with massive construction and 91.7% in modern light building. The average phase shift of temperature oscillations, expressed as a time delay of internal temperature rise behind the external temperature rise was about 2.8 hours and time delay of drop of internal temperature behind external temperatures drop was 3.3 hours in massive cowshed. The same parameters in modern light cowshed were only 1.1 hours and 0.5 hours.

Key words:

, , ,




82–90 P. Kic
Microclimatic conditions in the poultry houses
Abstract |
Full text PDF (361 kB)

Microclimatic conditions in the poultry houses

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamýcká 129, CZ 165CZ 21 Prague,
Czech Republic; Correspondence: kic@tf.czu.cz

Abstract:

The aim of this paper is to present the results of microclimatic research focused on the indoor conditions in several agricultural buildings used for fattening of chicken broilers. The attention is paid mainly to the construction of the building and its position in the farm area, which together with technological equipment of the building, floor covering, and system of ventilation, can influence the microclimatic conditions inside the halls. In the frame of this research main parameters of internal and external properties of climate were measured and evaluated. Themeasurement results of the air temperature, humidity, globe temperature, concentration of CO2, dust pollution and surface temperatures show rather important role of the overall layout of buildings, influence of the wind and solar radiation together with surroundings. The research results show that to the improvement of internal microclimate can contribute significantly the use of principles of passive air conditioning. The acquired new knowledge can be useful not only to improve the current situation on the farm, but mainly for the improvement of the building
constructions in similar new farms.

Key words:

, , ,




435-444 W. Bres and M. Jerzy
Changes of nutrient concentration in chrysanthemum leaves under influence of solar radiation
Abstract |
Full text PDF (142 kB)

Changes of nutrient concentration in chrysanthemum leaves under influence of solar radiation

W. Bres¹ and M. Jerzy²

¹Department of Horticultural Plant Nutrition , Poznan University of Life Sciences, Zgorzelecka4, 60-198 Poznań, Poland; e-mail: wbnaw@au.poznan.pl
²Department of Ornamental Plants, Poznan University of Life Sciences,Dabrowskiego 159, 60-594 Poznań, Poland

Abstract:

Eleven pot cultivars of the chrysanthemum (Chrysanthemum x grandiflorum /Ramat./ Kitam.) were grown in 12 year-round cycles. Starting with 2 January 2002, on the second day of each successive month, rooted cuttings of all the chrysanthemum cultivars were planted into pots 14 cm in diameter, 5 cuttings per pot. From the day of potting, the plants were exposed to short-day treatment. In periods of naturally long days, the day was shortened to 10.5 hours. From November till mid-February (days under 10 hours), no supplementary assimilation light was used to improve the light conditions in the period of insolation deficit. Depending on weather conditions, the electrolytical conductivity of the nutrient solution used for plant feeding varied between 1.8 mS cm-1 (in summer) and 2.2 mS cm-1 (in winter). To prepare the nutrient solution rainwater was used. When 30% of inflorescences were in flower, for chemical analysis well-developed leaves from plants were sampled. The total concentrations of macro- and microelements in plant tissue were determined. To find the relationship between nutrient concentration in plant tissue and radiation, data were analysed using simple linear regression models. Radiation had an effect on nutrient concentration in chrysanthemum leaves. The highest determination coefficient R2 for P and Ca, the lowest for N and K were calculated.

Key words:

, , , , ,