scholarly journals RESEARCH ON THE UNIFORMITY DEGREE OF SOLID ORGANIC FERTILIZERS DISTRIBUTION

2021 ◽  
pp. 495-504
Author(s):  
Vasilica Stefan ◽  
Ana Zaica ◽  
Adrian Iosif
Keyword(s):  
Wind Speed ◽  
Working Conditions ◽  
Experimental Research ◽  
Inclination Angle ◽  
Feed Rate ◽  
Organic Fertilizers ◽  
Material Function ◽  
Soil Fertilization ◽  
Number Of Factors

In this paper are presented the results of experimental research conducted in order to improve the uniformity of organic fertilizers distribution (compost and semi-fermented manure) used for soil fertilization, if the administration is done with a machine with a distributor with continuous spiral centrifugal beaters, arranged vertically. The uniformity of organic fertilizers distribution depends on a number of factors such as: the speed and angle of inclination of the distribution device, the distance between the distribution beaters, the humidity and the density of the material, wind speed, the size of the fertilizer particles. The determinations were performed under working conditions and the various parameters were the beaters speed, beaters inclination angle and the feed rate of the distribution device, choosing 3 situations (minimum, average and maximum) for each of them. Based on the obtained results, the multivariable functions of polytropic form was determined, which characterize the degree of uniformity of the spread material, function that can be the basis for the elaboration of constructive solutions to ensure the optimum uniformity of distribution.

scholarly journals Effects of central stabilizing barriers on flutter performances of a suspension bridge with a truss-stiffened deck under skew winds

2018 ◽  
Vol 22 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Ledong Zhu ◽  
Xiao Tan ◽  
Zhenshan Guo ◽  
Quanshun Ding
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Inclination Angle ◽  
Suspension Bridge ◽  
Control Measures ◽  
Wind Effect ◽  
Wind Condition ◽  
Wind Tunnel Tests ◽  
Critical Wind Speed ◽  
Bridge Span

To improve the flutter performance of a suspension bridge with a 1088-m-span truss-stiffened deck, the aerodynamic measures of upper and lower central stabilizing barriers were investigated at first via wind tunnel tests of sectional model under the normal wind condition. The yaw wind effect on the flutter performance of the bridge with the above aerodynamic measures was then examined via a series of wind tunnel tests of oblique sectional models. The test results show that the effect of the lower central stabilizing barrier on the flutter critical wind speed is remarkably different from that of the upper central stabilizing barrier for both the normal and skew wind cases. The inclination angle +3° is the most unfavorable inclination angle to the flutter performance of the truss-stiffened suspension bridge no matter whether the aerodynamic control measures are adopted or not. Furthermore, for most cases, the lowest flutter critical wind speed occurs when the incident wind deviates from the normal direction of the bridge span by a small yaw angle between 5° and 10°.

scholarly journals Comparison of logistic, energy and exploitative parameters of compost and manure application by spreaders

2017 ◽  
Vol 63 (Special Issue) ◽  
pp. S33-S39
Author(s):  
Souček Jiří ◽  
Pražan Radek ◽  
Roy Amitava ◽  
Plíva Petr ◽  
Jelínek Antonín ◽  
...  
Keyword(s):  
Working Conditions ◽  
Dry Matter ◽  
Agricultural Land ◽  
Matter Content ◽  
Organic Fertilizers ◽  
Dry Matter Content ◽  
Volume Weight ◽  
Lower Volume ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

This article deals with comparison of composts and manure use from the viewpoint of handling, transport and application on agricultural land. The published values were established by measurements under working conditions and afterwards converted on the basis of the content of nutrients defined in laboratory. Compost contained a greater share of nitrogen, phosphorus and potassium and had higher dry matter content and lower volume weight. Direct consumed energy expressed by recalculation of the consumed diesel fuel in case of composts moved from 5.12 MJ/kg (potassium) up to 16.19 MJ/kg (phosphorus). In case of manure it was higher and moved from 10.49 MJ/kg (nitrogen) up to 29.79 MJ/kg (phosphorus). The greatest share in energy consumption occupies transport, which was considered uniformly at the distance of 5 km. The study confirmed the feasibility of use of compost in agriculture as a partial substitute of conventional organic fertilizers; for its handling, transport and application the standard mechanization used for manure may be utilized.

scholarly journals Checking the conformity of the grain-size composition of road cement concrete mixtures

2019 ◽  
Vol 110 ◽  
pp. 01051
Author(s):  
Artur Onyshchenko ◽  
Sergii Aksonov ◽  
Vitalii Stozhka ◽  
Mykola Garkusha ◽  
Alexandr Matusevich
Keyword(s):  
Grain Size ◽  
Quality Control ◽  
Experimental Research ◽  
Size Composition ◽  
Cement Concrete ◽  
Grain Composition ◽  
Concrete Mixtures ◽  
Number Of Factors ◽  
Operational Quality

The article is devoted to operational quality control of grainsize composition of cement-concrete road mixtures for use on highways of Ukraine. The results of the experimental research are presented, which testify to the non-conformity of the planned grain composition to the actual production composition, as well as the influence on it of a number of factors that significantly affect the quality of the mixture and the durability of cement concrete.

Experimental Research on Conductor's Ice Accretion and Aerodynamic Characteristics

2014 ◽  
Vol 889-890 ◽  
pp. 497-500
Author(s):  
Han Jie Huang ◽  
Xin Min Li
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Wind Speed ◽  
Experimental Research ◽  
Lift Coefficient ◽  
Aerodynamic Characteristics ◽  
Ice Thickness ◽  
Sudden Increase ◽  
Ice Accretion ◽  
Power Project

For conductor commonly used in power project, research was conducted on its ice accretion and aerodynamic characteristics. Ice mass and ice shape were examined under various icing condition: time, temperature and wind speed. Ice mass increases linearly with time, while the growth rate varies significantly with wind speed. Ice mass does not increase with the fall of temperature; it reaches the max value in a relatively high temperature range of-5°C~-10°C. Ice shape and ice thickness are both important factors that determine conductors aerodynamic characteristics. Sudden increase of lift coefficient may happen at low attack angle for conductor with thick crescent ice shape.

Surface Roughness in High Feed Turning with Wiper Insert

2008 ◽  
Vol 375-376 ◽  
pp. 406-410 ◽  
Author(s):  
Zhan Qiang Liu ◽  
Peng Zhang ◽  
Peng Guo ◽  
Xing Ai
Keyword(s):  
Surface Roughness ◽  
Feed Rate ◽  
Machined Surface ◽  
Good Surface ◽  
Corner Radius ◽  
Number Of Factors ◽  
Machined Surface Roughness ◽  
High Feed ◽  
Good Surface Roughness ◽  
Coated Carbide

Surface roughness in a turning operation is affected by a great number of factors. Two of the most important factors are feed rate and the size of the corner radius. Surface roughness can be roughly determined to increase with the square of the feed rate and decrease with increased size of the corner radius. However, wiper insert geometries changed this relationship with the capability to generate good surface roughness at relatively higher feeds by transferring small part of the round insert edges into the straight cutting edges of the pointed insert. The principle of how wiper inserts behave different from conventional inserts as to the effects on the surface roughness is explored in this paper. Experimental study of the surface roughness produced in the turning of hardened mild steels using coated carbide tools with both conventional and wiper inserts is conducted. The test results prove the effectiveness of the wiper inserts in providing excellent surface roughness. The results also suggest that the use of the wiper insert is an effective way that significantly increases cutting efficiency without changing the machined surface roughness in high feed turning operations.

Influence of wind speed, stay cable inclination angle and wind yaw angle on formation of rivulets

2016 ◽  
Vol 22 (6) ◽  
pp. 508-515
Author(s):  
Jihong Bi ◽  
Ji Wu ◽  
Jian Guan ◽  
Jian Wang
Keyword(s):  
Wind Speed ◽  
Inclination Angle ◽  
Stay Cable ◽  
Yaw Angle

scholarly journals Composite Compost Produced from Organic Waste

2016 ◽  
Vol 10 (2) ◽  
pp. 43-50
Author(s):  
Radu Lăcătuşu ◽  
Romeo Căpăţână ◽  
Anca-Rovena Lăcătuşu
Keyword(s):  
Organic Waste ◽  
Marine Algae ◽  
Waste Water Treatment ◽  
Farmyard Manure ◽  
Farming Systems ◽  
Organic Fertilizers ◽  
Soil Fertilization ◽  
Composting Process ◽  
Organic Farming Systems ◽  
The Difference

Abstract The soil fertilization in ecological agriculture is done mostly using organic fertilizers. Some of them are prepared as compost from waste, but other haven’t, until now, any recycling possibility. In this context, for the preparation of new types of compost, we used three type of waste: sewage sludge from waste water treatment, marine algae and farmyard manure. We have made four different composting variants, each consisting of different proportions of the three waste: equal parts (33.33%) of each waste, 50% of each of the three wastes separately, the difference being made up in equal amounts (25%) of the other two wastes. Composting process was performed in Könemann silos (cubs with side by 1.20m) and lasted 60 days, from July 19 until September 16, when the composted material has passed the stages of reduction and oxidation. During composting process, in the reductive stage the material has reached a temperature up to 63°C Celsius, enough heat for its sterilization. Initial material, semi composted and final composted material were been chemical analyzed, especially in terms of macro- and microelements, analytical results revealing high and normal content of such chemicals. Therefore the achieved compost could be used in organic farming systems.

Experimental Research of Effective Cutting Speed Influence on Surface Roughness in Ball End Milling of C45 Material with Hardness 34 HRC

2014 ◽  
Vol 657 ◽  
pp. 53-57 ◽  
Author(s):  
Sándor Ravai Nagy ◽  
Ioan Paşca ◽  
Mircea Lobonțiu ◽  
Mihai Banica
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Experimental Research ◽  
Inclination Angle ◽  
Cutting Tool ◽  
End Milling ◽  
Cutting Speed ◽  
Cnc Machine Tools ◽  
Machined Surface ◽  
Ball End Milling

Machining of Complex Concave or Convex Surfaces Requires the Use of Ball End Milling Cutters. Obtaining the Expected Surface Quality Compete Various Technological Factors which should be Taken into Account. Following the Machining of the Surface with Different Inclination Angles between the Cutting Tool Axes and the Machined Surface, Significant Changes of the Surface Roughness have been Observed. Based on the Tests Performed, we can Determine the Range of the Tool Inclination Angle, which is the Best for the Surface Quality. we have also Made a Correlation between the Cutting Speeds, Inclination Angle of the Cutting Tool Toward the Machined Surface for an Obtained Surface Quality. the Presented Results are Based on Experimental Research in Industrial Conditions by Using CNC Machine Tools with 5 Axes. the Tests have been Performed on the C45 Material, Heat Treated to 34HRC.

scholarly journals Influence of Selected Working Conditions on Electricity Generation in Bifacial Photovoltaic Modules in Polish Climatic Conditions

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4964
Author(s):  
Arkadiusz Dobrzycki ◽  
Dariusz Kurz ◽  
Ewa Maćkowiak
Keyword(s):  
Working Conditions ◽  
Inclination Angle ◽  
Electricity Generation ◽  
Unit Cost ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Total Power ◽  
Rear Side ◽  
Energy Yield ◽  
Additional Energy

This paper discusses the conversion of solar irradiance energy into electricity. Double-sided (bifacial) panels are gaining increasing popularity in commercial applications due to the increased energy yield with a constant occupied mounting surface. However, the value of the additional energy yield produced by the back of the panel depends on several important factors. This paper presents the influence of working conditions on electricity generation in bifacial modules. This paper also investigates the influence of weather conditions, the module inclination angle, and the substrate beneath the panel surface on electricity generation. Fill factor and efficiency were calculated for each case included in the study scope. Based on the current voltage, power characteristics, and calculations, the module operation for different conditions was compared. It was observed that the optimal inclination angle to the surface is higher for the bifacial modules compared to the unilateral modules. The type of surface under the module has also been indicated to impact the amount of electricity generated. The additional energy yield associated with the panels’ rear side accounts for 2% to more than 35% of the total power generated by a photovoltaic (PV) module. The unit cost of electricity generation in the analyzed cases was also determined.

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