Applied Mechanics and Materials Vol. 772

Abstract: Through magnetic treatment of fuel before burner, the main factors influencing the burning process like fuel quality and spray quality undergoes changes, and the burning process is substantially improved. Acting on the fuel fluid with certain successive alternating polarity magnetic waves generated by permanent magnets, which is one of the innovative features of the system proposed in this paper, there is an intensification of the process of changing the stereochemistry of molecules, appearing fractionation, leading to increasing its magnetic moment and to their stronger ionization. These changes result in increased affinity of fuel molecules to other molecules and ions from close proximity, thus implicitly to oxygen molecules who have a strong paramagnetic behavior and the combustion of the fuel will take place in the upper parameters. In this paper is proposed, tested and validated by a series of experimental burning tests an innovative system used for magnetic treatment of combustible fluids before burner.

Abstract: The energy performances of the integrated thermal solar systems in the hybrid heating systems are influenced by several aspects like technology used and the way the collectors are placed, the type and technology of the heating storage, the operating temperatures in the hybrid system and last, but not least, the chosen control strategy. The operating regime of the thermal solar system characterized mainly by the thermal solar agent’s temperature and flow rate, as well as the corresponding control strategy, define the parametric framework of the system and impose its energy performances during operation. The optimized systemic variation of the temperatures and flow rates in both, the solar loop and the heating circuit, results in higher annual energy performances of the hybrid heating system. The present paper approaches the premises referring to the different operating regimes that characterize thermal solar systems in order to highlight and quantify their influence over the energy performances of the thermal system. In this respect, a set of computational operating simulations were carried out on the targeted system during one year of operation, in different configurations and operating regimes, for the energy assesment of the thermal system.

Abstract: In this paper is analyzed a stand-alone solar-wind hybrid system with energy storage in batteries installed on a farm in Romania. Because, after following the system operation, was discovered that the energy demand is not fully covered, two solutions were proposed. The optimization of the system was performed using iHoga, which is a simulation and optimization software based on genetic algorithms. A series of simulations have been conducted, with different configurations of the system, finally obtaining two optimal solutions for the hybrid system. The first solution proposes to increase the number of photovoltaic panels by 10 panels of the same type - System A, and the second solution proposes the installation of a generator - System B. Analyzing the two solutions was noted that in case of the System A, even if the initial investment is higher and produces a lot of excess energy, the total cost over the lifetime of the system is lower then in case of System B. Also, by comparing the two solutions, can be observed a high increase of carbon dioxide emissions in case of System B.

Abstract: Many programmable electronic modules for data acquisition and processing can be found in power systems. To monitor and record different specific high speed transient events in energetic systems, an adequate data acquisition and processing method is required. This paper deals with such method and its application in data acquisition for implementation of complex protection functions. The acquisition routine for analog and digital channels, detailed acquisition and storing process for analog and digital values, storing and calculation method for acquired digital and analog values are all presented. The proposed method is adequate for many and various practical applications which require high speed data acquisition systems.

Abstract: The objective of this contribution is to explore innovative ways to increase the efficiency of large scale photovoltaic systems (LSPVS) in the medium term through effective management of operating, monitoring and maintenance (OMM) costs based on aerial surveillance with small multi-rotor flight robot (s-MRFR). An effective solution of OMM cost assessment must capture the dynamic interaction between energy market developments, technological progress and investor tolerance to the risk posed by climate changes. The valuation method for OMM cost-risk analysis is based on generalized Wiener process with stochastic jumps. The interest is to increase the value of the investment by using innovative but efficient procedures of PV systems inspection based on aerial infrared thermography. The results are encouraging because the total costs of s-MRFR monitoring are very low compared to the benefits.

Abstract: The aim of this paper is to numerically explore the feasibility of designing a Mini-Hydro turbine. The interest for this kind of horizontal axis turbine relies on its versatility. In the present study, the numerical solution of the discredited three-dimensional, incompressible Navier-Stokes equations over an unstructured grid is accomplished with an ANSYS program. In this study, a mini hydro turbine (3kW) has been considered for utilization of horizontal axis impeller. The turbine performance and flow behavior have been evaluated by means of numerical simulations. Moreover, the performance of the impeller varied in the pressure distribution, torque, rotational speed and power generated by the different number of blades and angles. The results trends are similar between the highest pressure distributions at the impeller also produced highest power outputs on 6 numbers of blades at impeller. The model has been validated, comparing numerical results with available experimental data.

Abstract: As fossil fuels near depletion and their detrimental side effects become prominent on ecosystems, the world searches renewable sources of energy. Marine current energy is an emerging and promising renewable energy resource. Marine current energy can be alternative energy source for electricity production. Many marine current converters are designed to tap marine current energy; however, Gorlov turbine proves to have minimum manufacturing and maintenance cost, hence giving desired power output. A 0.3m diameter and 0.6m long 3 bladed Gorlov turbine was designed, fabricated and test to analyse its performance. The turbine produces average power 15 W and proves to be quite efficient for marine current energy extraction.

Abstract: Marine current energy is clean and reliable energy source. It can be alternative energy source to produce electricity if tapped with a suitable marine current energy converter. Pacific Island countries (PIC) like Fiji can reduce the amount of Fossil fuel used. However for most energy converters designed perform well at marine current velocities above 2m/s and it needs to be installed at depths of 20 – 40m also installation and the maintenance cost of such devise will be quite high if it needs to be installed in Fiji. Therefore a ducted cross flow turbine was designed, which can give desired output at minimum installation and maintenance cost. A dusted cross flow turbine has been design taking into account for its operating condition. The turbine was modelled and analyzed in commercial; Computational Fluid dynamic (CFD) code ANSYS-CFX. The code was first validated and with experiment results and finally performance analysis of full scale turbine was carried out. The designed turbine can have maximum efficiency of 56% producing rated power of 21kW; it produces 0.77kW at cut in speed of 0.65m/s.

Abstract: We have developed a movable stent motor in the blood vessel by applying the technique of the ultrasonic motor. We have also designed a stent motor which consists of two parts; a stator part and receiver part. The receiver unit obtains the ultrasonic wave from outside and the stator generates a driving force. The stator is the coil shape and it can move smoothly in intravascular. Adding that, we have designed the horn to provide ultrasonic energy to it from outside of human body. We have made experiments by the horn and the stent motor and we have succeeded in driving the stent motor in the water back and forth.

Abstract: In this paper, a new mechanism for human leg motion assistance for rehabilitation purposes has been proposed. The structure of human leg and its motions have been used as inspiration for design purposes. A 3D model of the proposed system has been elaborated in Solid Works®, both for design and simulation purposes. It is developed a kinematic model of the mechanism, useful for further design optimization. There has been build an experimental model of the mechanism and they are conducted experimental researches. The result shows that the proposed mechanism performs movements similar to those of a human leg.