Papers by Keyword: Power

Abstract: Fluid is a substance that can flow and conform to its container. Any substance or material that experiences movement or moves from one place to another will produce energy and this energy is strongly influenced by the physical properties of the fluid which is the source of this energy. Because of the same fluid properties, Savonius can also be applied to water flows. The Savonius waterwheel is a simple water-wheel that works because of the different forces on each blade. The concave blade (concave) facing the direction of the water will catch the water and force the blade to rotate on its axis and the convex blade (convex) which is pushed by the fluid flow also causes the blade to rotate even though there is a load caused by the convex part when pushed by the flow. This study determines to analyze efficiency and power of vertical shaft savonius water wheel with four blades and six blades on discharge variations. The best performance of the vertical shaft savonius water wheel with four blades is on load of 1.5 kg, the highest efficiency 17.16% and the highest water wheel power 1.317 watts with discharge of 0.629 m³/s. For the best performance of the vertical shaft savonius waterwheel with six blades on discharge 1 (0.629 m³/s) produced the highest power of 1.248 watt and the highest efficiency 15.92% at load of 1.5 kg.

Abstract: A thermoelectric generator can produce electrical energy using the extra heat from many sources, such as a Liquefied Petroleum Gas (LPG) cooking stove. This study aimed to examine the impact of varying LPG mass flow rates on the temperatures and power output of a thermoelectric generator (TEG). The LPG stove was altered by incorporating a hot side heat exchanger to enclose the burner, enabling the integration of four thermoelectric generators coupled in a series configuration. The temperature of the TEG hot and cold sides was measured using thermocouples and recorded using a data logger controlled by an Arduino. It is evident from the result that increased LPG mass flow rates cause the heat exchanger on the stove burner to heat up. There was a link between the temperature trend line of the TEG and the current, voltage, and power. The gas mass flow rates of 0.26 kg/h, 0.18 kg/h, and 0.14 kg/h correspond to power outputs of 3.09 W, 1.53 W, and 0.1 W, respectively. This study has demonstrated that installing a thermoelectric module on the LPG stove can serve as an alternate method to harvest the energy from the waste heat.

Abstract: Effective control of device geometry is key to mitigating high localized electric fields in next-generation SiC power devices. Advanced trench processing allows for highly tunable trench-gate architectures in trench MOSFETs. By utilizing a two-step inductively coupled plasma reactive ion etch (ICP-RIE) process, a high degree of trench base corner rounding can be achieved, irrespective of trench opening corner geometry prior to post etch treatments. Sentaurus TCAD device modelling highlights the importance of effective electric field dispersion at the gate oxide using rounded trench corners, while I-V characterization of fabricated trench MOS-capacitor devices demonstrate the influence of trench base corner rounding on gate oxide breakdown.

Abstract: The issues of constructing a control subsystem for adaptive control of technological processes on metal-cutting machines are considered. The implementation of control functions is carried out within the framework of adaptive control systems for cutting processes through the use of information about the power parameters of the cutting process, obtained on the basis of universal measuring converters. Measuring devices are an essential part of any adaptive control system and, in addition, have independent significance, since they can be used in systems for protecting equipment and diagnosing its condition. The quality of control and the reliability of measuring devices largely determine the effectiveness of the control system.

Abstract: The use of rechargeable batteries to store and distribute extra energy from photovoltaics (PV) improves the efficiency of solar energy generation. This study constructs a solar power plant system that is linked to the grid network and includes battery energy storage. The efficiency of a hybrid solar power plant with integrated batteries and grid energy storage is demonstrated and evaluated in this study. This study is based on real-time testing to determine battery utilization when different electrical loads for office use are combined. The workload profile during peak hours of use, which correspond to the peak time of sunshine, is used to evaluate the system. The collected findings show that the degree of effectiveness of this hybrid power plant fulfills the power simulation. During the peak irradiation time, the maximum power is 2100 watts, whereas the needed power simulation, which is 1900 watts in this case, so the power efficiency percentage is 110.52%. It means that PV can satisfy the charged power while also supplying extra power to the battery for usage at low periods. During the 8-hour test, the calculation of cost savings revealed a savings in electricity expenditure of Rp. 14,373. The energy storage system's real operational needs were met by battery storage and PV.

Abstract: Laser Surface Texturing (LST) has demonstrated to be the most reliable technique for the micro-modification of surfaces, allowing to obtain taylored surfaces. These modifications, depending on the basic micro-geometry and its repetition pattern, can provide special functionalities to a surface, such as hydrophilicity, hydrophobicity, reflectance, anti-bacterial, ostheo-integrability, as well as custom aesthetic, among others.Nevertheless, when a laser irradiates metallic surfaces, the micro-structure can be modified due to the heat induced, changing the mechanical properties of the surface. To avoid these effects, cold or ultra-short pulsed lasers must be used.A cold laser emits optical pulses with a duration below 1 ps (ultra-short pulses), in the domain of femtoseconds (fs=10^-15 s). These ultra-short pulses, combined with high frequencies, in the megahertz region, leads to pulse trains with high repetition rates. This allows the sublimation of the material, keeping it relatively cold due to the short exposition time to irradiation.Ti6Al4V is the most used Ti alloy, thanks to its excellent weight/mechanical properties ratio. Nevertheless, its tribological behavior is very poor. Although there is intense research to improve it by using LST, the study of the influence of femtosecond laser parameters in the desired micro-geometries is still a gap in the scientific literature.In this research, a study of the influence of power (up to 50 W) and frequency (up to 2 MHz) in the fs-laser texturing of Ti6Al4V is presented. Local pulse repetition, linear and surface textures have been studied by combining power and frequency in these ranges, evaluating the geometry obtained by variable focus microscopy. The study carried out has allowed to determine the optimal set of parameters as a function on the target texture geometry, as well as the range in which the LST removal process changes from sublimation (for texturing) to melting (for micro-machining).

Abstract: Coconut shell waste causes environmental pollution around the community. Therefore, it is necessary to have more optimal processing to produce valuable products using a microwave-assisted pyrolysis process. This study uses microwave-assisted pyrolysis (MAP) for the production of liquid smoke from coconut shells using different power (300, 450, 600 W) and sizes (1 mm, 2 mm, 3 mm). The results of this study show that the highest yield for 300 W power at 2 mm size by 22.85%, for 450 W power at 3 mm size by 28.52%, for 600 W power size 3 mm by 28.67%, while the optimal size for liquid smoke is 3 mm size by 31.95% at 450 W power.

Abstract: For machine design, determining the machine’s technical specifications as the basis for design element computation and choosing an appropriate electric motor are among the most crucial tasks. Especially, considering the scarcity of studies about tropical wood materials, it is more important to determine the specific work by the experimental approach. The scope of the study includes the research of dependency of the cutting power on the working parameters such as feed per tooth S_z, the cutting depth h, and the tooltip’s radius r in the process of wood material machining. Employing the response surface method, the experiments following the Central Composite Face design (FCCCD) plan were undertaken with 4 replicates. The author used Minitab software to process experimental results, analyze the regression equation and variance (ANOVA). In addition, the cutting force components in wood milling is also determined, which is the basis for the design of machine elements of wood milling machines and CNC woodworking machines.

Abstract: There are various base metals that might be subjected to friction stir welding (FSW). They have different yield strength, ultimate tensile strength and other mechanical characteristics that influence the complex phenomena of the FSW process. The nature, mechanical characteristic and other properties of the base metals introduce also certain requirements for the FSW equipment, because FSW is a mechanical process.Experimental data of the FSW of the following materials are presented and compared:- similar overlapped sheets of aluminium alloy EN AW 5754, having the thickness 1.0 mm; - dissimilar overlapped sheets of 3 - 6 mm thickness of the base metal couples: aluminium alloy EN AW 1200 / copper Cu 99 ET, aluminium alloy EN AW 5754 / copper Cu 99, aluminium alloy EN AW 6082 / copper Cu 99 ET;- sheets of nickel alloy, inconel 718, thickness 8 - 10 mm, by friction stir processing. The characteristics of the FSW tool are described and the main technology parameters are mentioned: overlap, rotational speed of the FSW tool, rotational direction, travel speed, thrust force, as well as electric current of the motor for the rotating motion of the tool.Other important factors are also taken into account: sizes and positioning of the sheets (up or down), rolling direction of the sheets, room temperature, temperature of the sheets, material and temperature of the support plate.The linear energy of the FSW process is the main parameter. This is an indirect parameter, because it must be calculated, based on the previous mentioned parameters. According to the definition, the linear energy depends directly on the mechanical power developed during the stirring process, respectively it depends indirectly on the travel speed.On the other hand, the heat input is directly proportional to the linear energy and the thermal efficiency of the transfer of the heat produced by the friction of the shoulder and pin, to the nugget zone, where the weld metal is produced. These quantities are also analysed.For these materials the power developed by the motor for the rotational movement is determined, as well as the mechanical torque applied to the FSW tool. All these data are important for the design of the FSW equipment, in order to realize its main technical characteristics, depending on the base metals.Conclusions on the results are exposed, with important consequences for the industrial applications of the FSW process.

Abstract: The longevity forecast is proposed to be implemented on the basis of models of degradation theory. The theory of degradation is developed as a general energy method for estimating the longevity of objects. It is based on the law of conservation of energy. To analyze the longevity of urban environment, it is proposed to adopt the simplest model of theory of degradation. The proposed work provides an explanation for the description of proposed model. The urban environment is divided into a number of simpler systems. The more the degree of system separation into simpler ones, the more accurately one can describe the behavior of the entire system in time. Each simple system is described by the simplest model of degradation theory. The general behavior of the system is understood as a simple sum of individual degradation models. A feature of the proposed theory is that the simplest model can describe the entire system or the sum of its individual parts at once. The model makes it possible to consider the issue of equalizing the longevity of individual systems. The analysis of durability of a multicompartment building is taken as an example. In terms of analyzing the given example, individual stages of systems operation, that are still subject to discussion, are identified.