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Development of a Low-cost Pressure Sensor
33-38Views:224In this paper development of a pressure sensor has been discussed. The main benefit of this sensor is relatively cheap compared to commercially available ones. The unit contains a beam type load cell and a pneumatic cylinder. The load cell has 4 strain gauges in Wheatstone bridge configuration in order to convert the change of resistance into measurable voltage. The system is well applicable in numerous circumstances, where digital pressure signal is necessary for control or data acquisition.
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Full-Scale Tests of Pipeline Girth Welds Under Complex Cyclic Internal Pressure and Static Bending Loading Conditions
76-82Views:95The critical elements of high-pressure hydrocarbon transporting pipelines are often the girth welds, which are subjected to complex loads. The aims of our research and this paper are to introduce our full-scale pipeline fatigue and burst tests applying cyclic internal pressure and superimposed external bending stress on girth welds, furthermore, attracting the importance and the applicability of the investigation results. A unique testing system was built to study the behaviour of pipeline girth welds under simultaneous loads. The tests were evaluated using video camera recordings, internal pressure vs. burst time functions and failure pressure values.
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Simulation Aspects of the High Pressure Die Casting Process
521-529Views:87High pressure die casting (HPDC) is a manufacturing process for producing accurately dimensioned, sharply defined, smooth or textured surface metal parts. It is accomplished by injecting liquid metal at fast velocity and under high pressure into reusable steel dies. Compared to other casting processes, die casting is at the top end of both velocity and pressure. The high velocity translates into a very turbulent flow condition. The process is often described as the shortest distance between raw material and the finished product.
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Global Inversion of Pressure Dependent Acoustic Velocity Data Based on a New Rock Physical Model
47-55Views:135In this paper with the further development of our previously published single exponential model, the new multiple exponential model describing the pressure dependence of acoustic longitudinal wave velocity is presented. Since with increasing pressure in the rock several relaxation mechanisms at the same time can cause the increasing propagation velocity, the new model can handle two or more physical mechanisms (e.g. the closure of pore volume or microcracks or friction on grain boundaries etc.). The previously applied linearized inversion procedure can trap in a local minimum, so during laboratory measured longitudinal velocity-pressure data processing a global optimization method was used to find the absolute minimum. Using the developed model equation as response equation in a Simulated Annealing algorithm the petrophysical parameters of the model can be determined. Inversion results proved that the calculated data using the new model and algorithm matched more accurate with measured data on a rock sample.
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Surface Activation of High Impact Polystyrene Substrate Using Dynamic Atmospheric Pressure Plasma
80-87Views:136Over the last decade, the number of researches has increased in the field of bonding technologies. Researchers attempt to improve surface adhesion properties by surface treatments. Adhesive bonding is one of these bonding techniques, where it is important to see what surfaces will be bonded. One such surface property is wetting, which can be improved by several types of surface treatment. In recent years, atmospheric pressure plasmas have appeared, with which research is ongoing on surface treatments. In our research, we will deal with the effects of plasma surface treatment at atmospheric pressure and its measurement. In addition, we summarize the theoretical background of adhesion, surface tension and surface treatment with atmospheric pressure plasma. Our goal is to improve adhesion properties and thus the adhesion quality.
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Casting Issues of Thick-Walled High Pressure Die Castings
159-166Views:143Die casting is a manufacturing process for producing accurately dimensioned, sharply defined, smooth or textured surface metal parts. It is accomplished by injecting liquid metal at fast velocity and under high pressure into reusable steel dies. Compared to other casting processes, die casting is at the top end of both velocity and pressure. The high velocity translates into a very turbulent flow condition. The process is often described as the shortest distance between raw material and the finished product.
Pre-fill is a process technique that is the result of significantly delaying the start of fast shot beyond the “metal at the gate” position. It can be stated as a percentage of cavity fill or as a distance beyond metal at the gate.
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Measurement of Friction Losses of Electro-Pneumatical Valves with Industrial Devices
68-72Views:85The pneumatic devices are frequently used in several fields of the industry but the losses and pressure
drops of the pneumatic system are not really investigated. These losses can cause great property damages during long uptime because the compressed air is a quite expensive energy source. I designed a measuring system which is able to measure the friction losses of electro-pneumatic 5/2-way valves (monostable and bistable too). It is possible to choose between manual and automatic operation modes as well. In the automatic mode the system makes measurements in three different user-defined pressure levels. In the manual mode the measuring pressure can be set between 2-6 bars. An automatic evaluate program is also an important part of the created system. It gives the possibility of the fast evaluation of the saved data and it could be the base of a fast report generating application. -
The Pressure Characteristics of the Released Gases from Sand Cores
73-79Views:142The core packages used for the production of castings are generally made from cores of different quality (no- bake phenol, HB-phenol, and HB-furan) and resin quantity, to meet the various requirements for the casting. In our research, the effect of the amount of resin on the pressure of the gases evolved from the cores was investigated. Experiments have shown that increasing the amount of resin has a different effect on different binder systems.
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Evaluating the Efficiency of Polyhedral Mesh Elements in Solving the Problem of the Flow around Ship’s Rudder
241-256Views:205Meshing is one of the crucial key features to the success of CFD based simulations, this study is evaluating the efficiency of polyhedral elements in solving the problem of the flow around ship rudder, using a Reynolds-averaged Navier-Stokes turbulence model (SST k-ω), and compares it to a tetrahedral based mesh, considering that polyhedral elements were neglected in the past due to difficulties in implementing them, this was solved by introducing a tool by ANSYS that converges tetrahedral elements to polyhedral element, and integrating it into FLUENT software, the model was validated by comparing it with previously validated model which used the full version of ANSYS, this study was concluded using the academic version, but still it was able to produce satisfying results in predicting the lift and the drag coefficient, the pressure around the rudder surface, the velocity and the turbulent kinetic energy, finally the mesh quality was evaluated using the orthogonal quality criteria, the results showed the supremacy of the polyhedral elements in saving time and computational resources and improving mesh quality, and keeping high level of accuracy in predicting the results.
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Thermoelastic Problems of Multilayered Spherical Pressure Vessels Subjected to Axisymmetric Loading
106-115Views:109This paper deals with the linear thermoelastic analysis of functionally graded multilayered spherical bodies subjected to constant mechanical and thermal loading. The temperature field is arbitrary function of the radial coordinate, the material properties and the radial body force vary according to power law functions along the radius of the sphere. An analytical method is presented to calculate the displacements and stresses within the multilayered spherical body. The method is expanded to tackle the problem of spherical bodies made from radially graded materials with temperature dependent material properties. The results are compared to finite element simulations and other methods.
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A study of pressure-sinkage relationship used in a tyre-terrain interaction
186-199Views:155The vehicle applies a normal load to the terrain, which causes sinkage and motion resistance. To forecast the normal pressure distribution on the interface of a vehicle–terrain and the tractive performance of a vehicle, the response of the terrain to normal load (which is characterized by pressure–sinkage relationship equations) must be measured. This paper presents the common conventional pressure sinkage models used in terramechanic and the modification that happened to this models. In addition the features of the new models.
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The Influence of the Boundary Conditions on the Buckling of Thin-walled Cans during Manufacturing
41-50Views:79In this paper the effect of the boundary conditions on the stability of thin-walled aerosol cans under axial pressure is investigated. The main objective is to outline the main characteristics of this highly nonlinear mechanical problem and to present methods to simulate the buckling of cans with different boundary conditions. Due to the numerical difficulties coming from the contact between the can and different components of the machines, the effect of the different supports of the can is investigated on the crushing (or buckling) force at which the loss of stability occurs. The commercial finite element software Abaqus is used to solve the problems and to present the efficiency of FE codes in the design process of cans.
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The Role of Industry 4.0 and Digitalization in agriculture, Especially in Romanian Agriculture
Views:387The use of robotics, automation, big data, artificial intelligence are growing in the world and in the agricultural sector, which contribute to the development of a more efficient agricultural sector. In the agriculture sector for sustainable development it is necessary the use of opportunities and technologies provided by industry 4.0. For the agriculture sector digitalization means the future, because it helps increasing output meanwhile environmental pressure is remitting, and is not increasing. The aim of these paper is to present the concept of Industry 4.0 in agriculture and to analyse the romanian agricultural sector attitude and conditions towards digitalization.
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Investigation on Double Oxide Film Initiated Pore Formation in Aluminum Casting Alloys
141-153Views:331The most common, and in fact, the most deleterious defects of aluminum casting alloys are the so-called double oxide films or bifilms, which have a central role in porosity formation, as they can easily unfurl and inflate into pores during the solidification of the alloys. Sr addition is generally used in the foundry industry for the modification of the eutectic Si phase of hypoeutectic Al-Si alloys. However, Sr microalloying usually leads to an increased pore formation tendency. As bifilms are preferred sites for pore formation, it should be expected that Sr additions have a significant effect on the number and/or the structure of double oxide films present in the melt. In this work, the relationship between Sr-concentration and the susceptibility to pore formation has been investigated through the evaluation of melt quality of melts which had different levels of Sr. The bifilm content of the melts was investigated by the analysis of K-mold specimens and X-ray computed tomography (CT) of reduced pressure test (RPT) samples. It was found that liquid alloys with a higher Sr concentration had a significantly greater tendency to pore formation, which can be explained by the presence of a larger number of bifilm defects in the liquid alloy.
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Relationship between Population Growth and Urbanization
527-541Views:436The main purpose of this article is to examine how to respond to and change the field of urbanization. Creating dwindling new opportunities and challenges for globalization, new sector introductions and agricultural dominance. In relation to changing trends in urban and rural environments, people's preferences are very diverse and their lives are changing. The difference between a big city and a small city can test different lifestyles. It is a fundamentally important infrastructure personality insurance system (both cities), important from the point of view of larger cities and very different from small towns in terms of quality. The benefits of small towns can be a unique lifestyle and a healthy lifestyle, which can certainly be felt. Among the different characteristics of urbanization in developing and developed countries, we can mention the different time course and magnitude [1]. Namely, in developed countries the urban explosion has taken place for a long time and with fewer people than in developing countries [2]. The rate of urban population growth in the latter group will be 4.04% between 1950 and 1975, 3.6% between 1975 and 2000, and 2.4% between 2000 and 2030. The Earth and all of humanity are facing many challenges these days, and this trend will continue in the future. The planet's overpopulation and changing eating habits put great pressure on agriculture and the countryside. Research focused on the countryside focuses on analyzing the various functions of rural areas.
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Rotational molding of plasma treated polyethylene/short glass fiber composites
103-108Views:154Rotational molding is a manufacturing technique for producing 3D hollow parts by adding plastic powder to a shell-like mold and rotating the mold while heating it with the powder. In contrary to the injection molding all the process operates at atmospheric pressure which makes reinforcement of the rotomolded product difficult. In this paper plasma treated PE and short glass fibers were dry mixed and used to produce composites by rotational molding process and characterized in terms of morphology and mechanical properties.
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Servant, Ethical and Authentic Comparative Analysis of Leadership Styles in the Light of the Challenges of the BANI World
1-10Views:32In a globalised and accelerated economy, managers are under increasing pressure to reconcile organisational goals that are independent from human being with the reality of human relationships. The human being, as a being with intellect and senses striving towards happiness, is the focus of positive leadership styles and is their major concern in the field of management theory. In this article, three such positive styles, authentic, servant and ethical leadership principles and their operating conditions are compared using international literature. The literature time span of about two decades shows that the evolution of the ethical leadership literature has slowed down, while the authentic and servant leadership literature has continued to evolve and is still evolving today. The comparative table that appears in this study highlights both commonalities and distinctions, in that, in addition to high moral and ethical standards, the authentic style focuses primarily on the person of the leader, the ethical leader on the ethical standards of the organisation, while the servant leader focuses on the development of the well-being of the subordinate, the other person, even through self-sacrifice. We intend to use the results of this research to investigate measures of positive styles, preparing the scientific ground for future primary empirical field studies.
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Analysis of a Special, 3D Metal-Printed HPDC Tool Material
251-265Views:168High Pressure Die Casting (HPDC) is still the most productive metal-casting method of our time, however the more demanding are the industrial expectations, the more challenging it becomes to ensure the creation of the difficult cavity geometries and the thermal balance of the die-cast tool. New perspective is required, thus we can utilize high heat-conductivity tool steels and additive manufacturing technology.
