scholarly journals A Characteristic of Selected Properties of Vulcanised Rubber Elements Used on the “Izabel” Inland Vessel

2018 ◽  
Vol 1 (1) ◽  
pp. 675-679
Author(s):  
Patrycja Pawłowska ◽  
Zbigniew Matuszak ◽  
Katarzyna Sosik ◽  
Mária Chovancová
Keyword(s):  
Hardness Test ◽  
Weather Conditions ◽  
General Concept ◽  
Operating Conditions ◽  
Shore Hardness ◽  
Final Phase ◽  
High Elasticity ◽  
Static And Dynamic Loads ◽  
Main Components ◽  
Elastic Deformability

Abstract Vulcanised rubber as a complex system is made from the basic component being virgin rubber and various components amounting to 10-15 per cent or even more. The material gains its most valuable properties in the final phase of processing i.e. vulcanisation. In mechanical as well as automotive engineering it is important for vulcanised rubber to be resistant to grease, oil and fuel in high operating temperatures. Being one of the very valuable isolation materials, vulcanised rubber is also characterised by dielectric and elastic properties as well as distinguished resistance to operating conditions (high/low temperature, weather conditions). All the above mentioned applications of vulcanised rubbers are also found in the shipyard industry. Their use is also very much predicated on the properties such as: ability to attenuate mechanical vibrations, high elasticity, considerable elastic deformability under static and dynamic loads, low permeability of water and gas, resistance to various chemicals, and other. The purpose of this article was to determine the hardness of vulcanised rubber samples obtained from various places on the “Izabel” inland barge. The scope of the study covered sampling and preparing the samples for testing (i.e. cleaning and degreasing the samples). Then, the hardness of the samples was measured using the Shore hardness test. The first part of the article presents the general concept of vulcanised rubber, its main components, properties, applications, and ageing. The second part focuses on the research scope and measuring the hardness of vulcanised rubber samples obtained from the “Izabel” inland barge.

scholarly journals Performance optimization of polymeric porous membrane-based liquid desiccant air dehumidifier used in air conditioning system

2019 ◽  
Vol 11 (1) ◽  
pp. 55-71
Author(s):  
Ali Mohammad Jafarpour ◽  
Farivar Fazelpour ◽  
Seyyed Abbas Mousavi
Keyword(s):  
Performance Optimization ◽  
Air Conditioning ◽  
Weather Conditions ◽  
Porous Membrane ◽  
Operating Conditions ◽  
Regeneration System ◽  
Liquid Desiccant ◽  
Air Conditioning System ◽  
Air Stream ◽  
Improved Performance

AbstractIn this study an experimental design was developed to optimize the performance and structure of a membrane-based parallel-plate liquid desiccant dehumidifier used in air conditioning regeneration system which operates under high humidity weather conditions. We conducted a series of polymeric porous membranes with different compositions fabricated that were prepared with various weight percentages of polysulfone (PSU), mixed with N-methyl-2-pyrrolidone (NMP) and dimethyl form amide (DMF) solvents. Furthermore, the designed experiments were performed under various operating conditions, indicating that the dehumidification efficiency declines with increasing flow rate, temperature, and humidity. Consequently, a membrane with optimized porosity and moisture permeability was selected which resulted in eliminating the carryover of solution droplets in the air, largely due to separating the flow condition of liquid desiccant (Li Cl) and air. This specific design is also greatly benefited by removing the water vapor from the air stream. The results of mathematical model simulations indicate that the DMF solvent had higher dehumidification capability compared with that of NMP under the optimized operating conditions. Additionally, it can clarify the porosity of the membrane which plays a significant role in the overall performance. Therefore, the fabricated membrane produces fresh cool air, and it can be applied as a guiding sample for designing the membrane-based dehumidifier with improved performance.

Transient Considerations of Flat-Plate Solar Collectors

1974 ◽  
Vol 96 (2) ◽  
pp. 109-113 ◽  
Author(s):  
S. A. Klein ◽  
J. A. Duffie ◽  
W. A. Beckman
Keyword(s):  
Flat Plate ◽  
Solar Collector ◽  
Meteorological Data ◽  
Weather Conditions ◽  
Operating Conditions ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Thermal Capacitance ◽  
Flat Plate Solar Collector ◽  
Capacitance Effects

The effects of thermal capacitance in the modeling of the performance of a flat plate solar collector have often been neglected because of the computation involved. But because the solar collector is inherently exposed to continuously variable weather conditions, capacitance effects may be significant. To investigate these effects, three different models of flat-plate collectors have been investigated. The first, a quasi-steady-state model, simulates the performance of a collector of zero capacitance. The second model accounts for capacitance effects by assuming that a single value of thermal capacitance can be determined for the collector as a unit. The third model divides the collector into many isothermal segments, or nodes. For all three models the heat transfer coefficients are calculated as a function of operating conditions. The results show that, when hourly meteorological data are used, the zero-capacitance model is adequate.

Investigating the Impact of Rainfall on Travel Speed

2014 ◽  
Vol 71 (3) ◽  
Author(s):  
Nordiana Mashros ◽  
Johnnie Ben-Edigbe ◽  
Hashim Mohammed Alhassan ◽  
Sitti Asmah Hassan
Keyword(s):  
Empirical Studies ◽  
Heavy Rain ◽  
Weather Conditions ◽  
Travel Speed ◽  
Operating Conditions ◽  
Speed Reduction ◽  
Light Rain ◽  
Rainfall Condition ◽  
Adverse Weather ◽  
The Impact

The road network is particularly susceptible to adverse weather with a range of impacts when different weather conditions are experienced. Adverse weather often leads to decreases in traffic speed and subsequently affects the service levels. The paper is aimed at investigating the impact of rainfall on travel speed and quantifying the extent to which travel speed reduction occurs. Empirical studies were conducted on principle road in Terengganu and Johor, respectively for three months. Traffic data were collected by way of automatic traffic counter and rainfall data from the nearest raingauge station were supplied by the Department of Irrigation and Drainage supplemented by local survey data. These data were filtered to obtain traffic flow information for both dry and wet operating conditions and then were analyzed to see the effect of rainfall on percentile speeds. The results indicated that travel speed at 15th, 50th and 85th percentiles decrease with increasing rainfall intensities. It was observed that allpercentile speeds decreased from a minimum of 1% during light rain to a maximum of 14% during heavy rain. Based on the hypothesis that travel speed differ significantly between dry and rainfall condition; the study found substantial changes in percentile speeds and concluded that rainfalls irrespective of their intensities have significant impact on the travel speed.

Pengaruh penambahan propana dalam bahan bakar terhadap karakteristik sel tunam oksida padat

2018 ◽  
Vol 4 (1) ◽  
pp. 159
Author(s):  
Isdiriayani Nurdin ◽  
Astrilia Damayanti ◽  
Ocktavianus Lede M. R. ◽  
Pramujo Widiatmoko
Keyword(s):  
Cell Voltage ◽  
Life Time ◽  
Operating Conditions ◽  
Optimum Operating ◽  
High Alumina ◽  
Test Results ◽  
Fuel Gas ◽  
Aisi 304 ◽  
Negative Effect ◽  
Main Components

AbstractFuel cell is a renewable energy source that does not create any negative effect to the environment. One of the advantage of the Solid Oxide Fuel Cell (SOFC) is its tolerance to fuel contaminants. This research is aimed to study the effect of propane addition into fuel gas on SOFC'S characters. SOFC tested during this research consists of main components functioned as feed gas distributor, and insulator made of asbestos and C-12 high alumina. SOFC's characters studied in this research including optimum operating conditions, polarization, and expected life time of the cell. The test results show that optimum operating conditions of tested SOFC are 700ºC, 45 mL H/minute and 225 mL air/minute. Cell using 22,2 %-vol propane in the fuel gives a longer lifetime, a smaller maximum current, and a higher voltage efficiency than such using hydrogen only as fuel. Propane concentration in fuel gas up to 22,2 %-vol has not any significant influence to cell voltage. The obtained polarization curve reveals that cell reactions are mass transfer controlled.Keywords: SOFC, Life Time, Polarization, EfficiencyAbstrakSel tunam oksida padat (SOFC) merupakan salah satu sumber energi terbarukan yang tidak menimbulkan dampak negatif terhadap lingkungan dan toleran terhadap kontaminan dalam bahan bakar. Tujuan percobaan ini adalah mempelajari pengaruh penambahan propana dalam bahan bakar terhadap karakteristik SOFC. Pada penelitian ini SOFC yang diuji terdiri dari komponen utama sel tipe ASC1 buatan lnDEC B.V,dilengkapi dengan cangkang terbuat dari stainless steel tipe AISI 304, yang merangkap sebagai distributor gas umpan, dan isolator dari bahan asbes serta semen tahan api tipe C-12 high alumina. Karakter SOFC yang dipelajari pada penelitian ini meliputi kondisi operasi optimum, polarisasi, dan umur set. Hasil percobaan menunjukkan bahwa operasi SOFC optimal pada temperatur 700ºC dengan laju alir H2, 45 mL/menit dan udara 225 mL/menit. Konsentrasi propana dalam bahan bakar 22,2 %- v memberikan umur sel yang lebih panjang, arus maksimum yang lebih kecil, dan efisiensi tegangan yang lebih besar daripada dengan bahan bakar gas hidrogen saja. Konsentrasi propana dalam gas bahan bakar sampai dengan 22,2 %-v tidak mempengaruhi tegangan sel. Kurva polarisasi yang diperoleh menunjukkan bahwa reaksi sel terkendali olehperpindahan  massa.Kata Kunci : SOFC, Umur, Polarisasi, Efisiensi

Design and Implementation of Elevator Monitoring Terminal

2014 ◽  
Vol 926-930 ◽  
pp. 1253-1256 ◽  
Author(s):  
Shi Hong Li ◽  
Hui Pu Hu ◽  
Yan Jin
Keyword(s):  
Effective Means ◽  
Computer Software ◽  
Operating Conditions ◽  
Monitoring And Control ◽  
Special Equipment ◽  
Security Issues ◽  
Government Supervision ◽  
Communication Module ◽  
Main Components ◽  
Network Server

Concerning the security issues in the running elevator and the fact that elevator monitoring is an effective means to ensure the safe running of the elevator, and the special equipment, users, manufacturers, and government supervision departments will need to master the operating conditions of the elevator. Therefore, combining with the main components, embedded microprocessor, RF communications modules, sensors and GPRS designed the remote elevator monitoring terminal, and complete real-time acquisition of the state data of the running elevator via GPRS communication module to send data to a remote network server. Monitoring terminal cooperates with the web server, database, and host computer software, then realize the remote monitoring and control of the elevator group. Practice has proved the feasibility, effectiveness and reliability of the design of the monitoring terminal.

Study of Photovoltaic Systems’ Performances with Different Module Types

2016 ◽  
Vol 856 ◽  
pp. 279-284 ◽  
Author(s):  
Zahari Zarkov ◽  
Ludmil Stoyanov ◽  
Hristiyan Kanchev ◽  
Valentin Milenov ◽  
Vladimir Lazarov
Keyword(s):  
Theoretical Study ◽  
Weather Conditions ◽  
Operating Conditions ◽  
Experimental Results ◽  
Photovoltaic Systems ◽  
Experimental Site ◽  
Pv Systems ◽  
Research Platform ◽  
Pv Modules ◽  
Different Types

The purpose of the work is to study and compare the performance of photovoltaic (PV) generators built with different types of panels and operating in real weather conditions. The paper reports the results from an experimental and theoretical study of systems with PV modules manufactured according to different technologies and using different materials. The experiment was carried out at a research platform for PV systems developed by the authors, built and located at an experimental site near the Technical University of Sofia. Based on the obtained results, comparisons are made between the different PV generators for the same operating conditions. The comparison between the theoretical and the experimental results demonstrates a good level of overlap.

scholarly journals Study of Reliability for Main Components and Devices of Die-Cutting Presses for Packaging

2020 ◽  
Vol 19 (4) ◽  
pp. 320-328
Author(s):  
N. S. Kohnenko ◽  
I. I. Karpunin ◽  
V. V. Kuz'mich
Keyword(s):  
Failure Probability ◽  
High Performance ◽  
Residual Life ◽  
Operational Reliability ◽  
Operating Conditions ◽  
Single Type ◽  
Successful Operation ◽  
Urgent Task ◽  
Probabilistic Values ◽  
Main Components

A large variety of machine operating conditions leads to a difference in the wear rate even for their units being of the same type. Operational time terms of single-type units and machines are not the same, and therefore, numerical expressions of operational reliability will be probabilistic values. Incomplete restoration of original properties of a unit, a negligent repair, a poor maintenance usually lead to the fact that any of several parts independently one from another can determine reliability  of  a  machine  (a unit).  This is especially important  to  consider  when  manufacturing packaging in order to avoid rejects. The operational reliability of modern machines consisting of hundreds, and sometimes thousands of parts, wear processes of which are in a complex relationship,  depends on a number of factors. A study on reliability of main components and equipment devices is an urgent task. Successful operation of printing equipment is possible only if there is a clear organization of preventive work, ensuring preparation of printing machines for printing and post-printing processing. High-performance equipment, such as die-cutting presses, should be regularly inspected, adjusted and maintained in such a way as to obtain standard results at the output. The paper has studied reliability of main components and devices of die-cutting presses based on calculation of failure probability. Calculations have been carried out by analogy with the calculation of the probability of events in the fault tree. Failure diagrams of devices and units of die-cutting presses have been built in the paper. Based on the analysis of the failure probability for main components and devices, graphs of residual life for equipment operation on its life cycle have been constructed in the paper.

scholarly journals Influence of the Processes Occurring in the Movable Interfaces of the Parts of Transport Machines Under the Action of the Components of the Geomodifier on the Efficiency of Tribotechnologies of Running-in and Recovery

2020 ◽  
pp. 250-265
Author(s):  
Viktor Aulin ◽  
◽  
Sergey Lysenko ◽  
Andriy Grinkiv ◽  
Andriy Chernai ◽  
...  
Keyword(s):  
Nonequilibrium Thermodynamics ◽  
Protective Coatings ◽  
Operating Conditions ◽  
Working Environment ◽  
Physical Processes ◽  
Friction Zone ◽  
Transmission Oil ◽  
Main Components ◽  
Aluminosilicate Mineral ◽  
Degree Of Fragmentation

It is shown that the effectiveness of the implementation of tribotechnologies for running-in and restoration of systems and assemblies of transport machines depends on the preparation of the working environment in which the running-in of tribocouplings of parts takes place. When using a geomodifier to add to engine and transmission oil, it is important to refine the particles of its components and obtain special properties of their surfaces. The properties of the main components of the KGMT-1 geomodifier: SiO2, MgO, Al2O3, Fe2O3 are considered. Their activation during grinding and feeding into the friction zone is substantiated. The change in the size of the particles of the components of the geomodifier on the duration of the test under various operating conditions and within the limits of the strength intervals was investigated. The course of various physical processes according to nonequilibrium thermodynamics and the realization of states and processes of self-organization are considered. It was found that, depending on the degree of fragmentation, the particles of the components exhibit different activity, and therefore, different conditions for the formation of protective coatings on the working surfaces of parts and tribomechanical and tribophysical effects on particles are realized. It is shown that the latter manifests itself during the formation of defects, specific surface area, and duration of mechanical activation. It was revealed that for the materials of the KGMT-1 geomodifier components with strongly homeopolar bonds, such as SiO2, SiC, and the aluminosilicate mineral kaolinite, an amorphization process is observed. The influence of the α-Si-k-Si phase transformation in the materials of the KGMT-1 additive on the efficiency of the implementation of tribotechnologies has been determined. It is shown how physical processes in a composite oil cause tribochemical reactions and formation of coatings on the working surfaces of interfaces of parts of systems and aggregates of transport machines.

scholarly journals THE ROLE AND BEHAVIOR OF THE INDIVIDUAL IN THE DEVELOPMENT OF SOCIAL CAPITAL

2021 ◽  
Vol 2 (1) ◽  
pp. 39-44
Author(s):  
Natalia Rіabinina
Keyword(s):  
Economic Growth ◽  
Social Capital ◽  
General Concept ◽  
Economic Behavior ◽  
Economic Changes ◽  
Economic Concept ◽  
The Future ◽  
Main Components ◽  
The Individual ◽  
And Behavior

At the intersection of the past and the future there is a point of present, which, due to external and internal socio-economic requirements, activates the subject himself, when uniting the sciences of economics and sociology, as well as psychology, philosophy and law, we see the development of a new scientific direction - social capital. Interdisciplinary and multi-vector methodological conception on development has the capabilities to use in all spheres of life, to develop a more productive and inclusive economy because it works directly with people and for people. The development of society and the formation of institutions of citizenship and economic growth are inherently connected with the new economic and social concept, which is an incentive for self-organization, and the establishment of interpersonal and intergroup relations, leading to a path of harmonization based on sincere help and trust. Formulation of the goals and objectives of the article (setting a task). A large amount of research on social capital, a wide and diverse direction of study directly inhibits the systemicity and orderliness of concepts and theoretical knowledge, so at the beginning of the study it is necessary to put problems, tasks, a place in the knowledge system and connection with other disciplines. The purpose of the study is to separate and determine the individuality of a person in the process of social capital, attitude and behavior of the individual and group at all levels of this concept, analysis, specifics and structural content of social capital. Methodology. During the research, to study and achieve the goal, the analysis of theoretical aspects and generalizations of scientific sources, dialectic cognition of the formation of social capital, revealed a kind of economic concept, methods of induction and deduction, abstraction of theoretical provisions and dialectic cognition were carried out. Results. The article raises the issue of the resource of socio-economic growth and improvement, on the basis of intergroup and interpersonal interactions and relationships at a high micro level, on the foundation of trust and cooperation between people, single work and development of state, economic, civic platforms. It is with humans that the mechanism of development, accumulation and effective use begins. The accumulation of individuality in the development of social capital of the economic system and the main components of social capital, such as trust and reliability, are studied. The analysis of economic behavior of the individual when making a rational decision in the world of economic changes is carried out. The practical component of the main provisions of the concept and levels of social capital, and its role in the general concept of the economic component can further develop and be used in the process of developing the analysis and development of the individual with individual behavior and personal decision-making. Value/originality. The theory of social capital itself is new and little-studied, so any vector of study and research gives a new impetus to interest and further development of the detection of theoretical aspects, generalization to definition and essence, outlining the main directions of development and formation for the future.

Development of main components of device for measuring residual stresses

2019 ◽  
pp. 65-69
Author(s):  
N. F. Wroblewski ◽  
P. N. Gerasimov ◽  
O. A. Korotky
Keyword(s):  
Stress State ◽  
Residual Stresses ◽  
Measurement Errors ◽  
Operating Conditions ◽  
Electromagnetic Properties ◽  
Machine Elements ◽  
Main Components ◽  
Object Material ◽  
Magnetic Resistance ◽  
The Impact

The paper presents the results of the study of the stress state of machine elements and structures in which there are residual stresses. Examines the use of overhead eddy current and magneto-elastic transducers, investigates the process of measurement of residual stresses. It is proved that the cause of measurement errors is the instability of the gap between the transducer and the surface of the object. It is proved that during calibration and measurements, the installation of the gap and its control should be carried out by the magnitude of the magnetic resistance. Undesirable effects of variable electromagnetic properties of the object material on the installation result can be eliminated by using the method of vortex currents. As a result, a device for measuring the stress state of objects made of ferromagnetic metals has been developed, which uses a magnetoelastic converter. Using the values of the frequency increment of the corresponding oscillator, it is possible to significantly reduce the impact of changes in operating conditions on the measurement result.

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