This paper presents a general theory regarding the balancing of mechanisms. It starts with Stevenson’s theory , which proves that any mechanism can be dynamically perfectly balanced if there is a pair of counterweights that are eccentrically positioned in three reciprocating perpendicular axes, passing through the mass center of the body. The system of inertial forces are extended in Fourier series where only the first terms, the basic harmonics, are considered. The proposed goal is to stultify the effect of inertial forces and torques. This paper deals with a situation more appropriate to reality. In common cases there doesn’t exist the possibility of implementing counterweights in three perpendicular axes. In this situation only the minimization of inertial forces and torques remains as a possible solution. The method developed for this case is presented.
Ana Camelia Sauca, Tudor Milchiș and Ferdinánd-Zsongor Gobesz
A fully 3D numerical analysis of turbulent flow over a cluster of solar photovoltaic (PV) panels was performed in order to assess the total drag and lift forces, comparing the results with the values from the guidelines of the national standard. A Reynolds-Averaged Navier–Stokes (RANS) model was used in the numerical simulations, considering two acting directions of the wind along the length of the array (0 degree – front, and 180 degrees – reverse direction).
This paper deals with criteria and conditions that must be fulfilled by a modern grinding wheel dressing system. Its main task is the correct drawing of the given profile. By this task, the diamond pin’s axis must close during the motion at a constant angle with the normal of the wheel’s surface. This study presents the build-up and the proposed control strategy of the dressing device. Two control methods were analysed and compared.
Nowadays more and more ultralight aircraft are being built because the building process itself and the acquisition of the necessary documentation is relatively easy. Furthermore, these planes are easier to fly than larger types of aircraft. This article presents the engineering work and documentation that is necessary for the building process. The calculations can be done traditionally on paper which is an extremely complex task. With the innovations and developments in the technical field though, it is possible now to simplify these calculations, the basis of which is the finite element method and aerodynamics simulations. If the finite element method is adequate, the boundary conditions are ideal and input-output settings for the simulations are correct, it is possible to compare the traditional calculations to the modern simulated engineering work, thus the time necessary for achieving precise results becomes significantly shorter.
Csaba Ungvári, Andrea Izbéki-Szabolcsik and Ildikó Bodnár
In our research we pre-treated synthetically produced greywaters with filtration on various filters. We characterised the quality of greywater samples using several parameters. We investigated these parameters on the untreated and pre-treated samples as well. We evaluated the efficiency of the treatments by measuring the characteristic parameters. It was shown that the most effective pre-treatment for the greywater’s preparation for reuse is filtration on silica sand or activated charcoal and silica sand combined filter media.
András Gábora, Kristóf Balázs Sipos, Gyula Dávid Lovadi, Attila Szántó, Gusztáv Áron Szíki and Marian Borzan
The Faculty of Engineering of the University of Debrecen has more than ten-years of experience in developing vehicles with pneumatic drive. It is an increasing challenge for the developer teams to improve the performance of vehicles, with rules becoming increasingly strict year by year. Recently, a student team of the Faculty of Engineering began developing a telemetric system to support the other teams at our Faculty and improve the possibility of their successful racing in this way.
The technological advantages of ultrasonic welding: (no requirement for filler metal; use of small electrical transient resistance contacts; ability to weld thin materials to thick materials) results in a helium-solid weld seam; the computer configuration of the welding parameters can easily be solved; clean and safe workflow (no sparks, flame or smoke); can be integrated into the production line. This article deals with some of the additional application features of this welding process.
Roland Nagy, Péter Lendvai, Réka Kothencz and László Bartha
The efficiency of demulsification is a key process in terms of extracting the oil of O/V (oil-in-water type) emulsions of enhanced oil recovery. Consequently, the separation of emulsion systems and the recovery of the maximum amount of oil from the colloid system play an important role in the petroleum industry. The stability of the emulsions from oil recovery is influenced by numerous factors. J. L. Salager developed the HLD (Hydrophilic-Lipophilic Deviation) equation in order to examine the efficiency of demulsification. Our aim was to investigate whether the equation developed by Salager is suitable for monitoring the stability of petroleum industrial emulsions.
Sándor Uszkai, Beatrix Papp, Ádám Nemes and Timotei István Erdei
Nowadays the ongoing trend of integrating everything into the cloud, connecting all sorts of gadgetry to the Internet (IoT) is omnipresent at this point, even in the industry, where small and medium sized companies alike can join this tendency. This is undoubtedly the result of the arrival of Industry 4.0, which caused an exponential growth in this field. This poses a new challenge for the IT field, since it needs in-depth knowledge of networking and routing, and formidable knowledge of the different devices and programming languages alike. Our project premises an RFID-based fully-fledged access control system, with a targeted market of small to large companies, and also individuals, as the result of ease of use, low price, and simplicity.