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This paper aims to numerically analyze the stress of two aluminum structures for a single-column small-scale tensile test machine. Initially, aluminum structures were designed using Autodesk Fusion 360 software, and then the designs were simulated with static simulation analysis using Autodesk Fusion 360 software. This simulation assess the stress distribution, maximum deflection and safety factor of two different aluminum structure when loaded with 1 kN, 3 kN and 5 kN loads, as a simulated tensile load. The results show that both aluminum structure could withstand up to 5 kN load in elastic zone but one has significantly higher rigidity, which made it more suitable to be used as a tensile test machine frame. Overall, it can be concluded that the aluminum structure could be applied for a single-column small-scale tensile test machine. [ABSTRACT FROM AUTHOR]

The simultaneous provision of electrical and thermal energy is made possible using PVT technology. By removing heat through the coolant, this dual action can lower the operating temperature of the panel. By lowering the operating temperature of the panel in this manner, the electrical efficiency of the solar cell may be enhanced. This study aims to determine how the dispersion of copper (Cu) and nanoparticles in pure water impact this PVT system's performance. The research was conducted using modeling in a CFD approach derived from developing an energy equilibrium system in PVT solar cells. ANSYS18.2 is used to represent the temperature distribution that takes place in the collector. The validity of the tested and created numerical model is examined using the ANOVA approach. According to the results, using Cu-water nanofluids at a concentration of 1 percent can increase system performance more than using alternative designs. The findings also demonstrate that thermal and electrical efficiency may be increased by 52.75 percent and 11.927 percent, respectively, by utilizing a volume fraction of 1 percent of Cu nanoparticles. Comparing this gain in efficiency to the addition of other concentrations, the difference is incredibly minor. [ABSTRACT FROM AUTHOR]

A substance known as a phase change material (PCM) may absorb or release heat by altering its physical properties. Alterations in the liquid and solid phases are among the possible changes. Research to include PCM in the Thermal Collector System was conducted to identify the nature of PCM in absorbing heat. This study looked at how adding Phase Change Material (PCM) to the cooling rate affected how much heat accumulated in the collector. In this investigation, the PCM types RT64HC and SP70 were employed. By applying the energy balance equation to the melting and solidification processes in PCM, mathematical modeling that has been predetermined is used to carry out the study. ANSYS18.2 represents the temperature distribution in the collector—validation of mathematical models that have undergone testing and development for the following phase. The outcomes show that adding PCM can lower the collector's temperature and improve the collector's cooling effectiveness. Despite a little difference, PCM type RT64HC has a superior cooling rate than SP70. Temperature measurement on the RT64HC yielded a value of 300.19 K and a cooling effectiveness of 99.08%. The SP70, the other hand, has a temperature of 300.45 K and a cooling efficiency of 98.05%. This outcome is superior to the 305.82 K temperature and 74.83% cooling efficiency of the cooler on the collector without a PCM. [ABSTRACT FROM AUTHOR]

The efficiency of photovoltaic (PV) solar cells may be increased by lowering the operating temperature thanks to Photovoltaic Thermal Collector (PVT) technology. Additionally, the working fluid in the collector generates heat energy concurrently with the collected heat. This article uses the CFD method to develop modeling thermal collectors with three different material variations for increased-performance panel photovoltaics. The phenomena of heat transmission are simulated using ANSYS 18.2. The natural convection of the PV cell layer was investigated using ANSYS Steady State-Thermal, and the heat transfer between the PV cell layer and the liquid was simulated using ANSYS Fluent. The overall system efficiency of the energy-generating system was raised by 62.67% by employing a heat collection system to cool PV solar cells. PV solar cells have the maximum electrical efficiency rating when the collector arrangement is modeled using aluminum material and the working fluid in Al2O3 nanofluid at a plate thickness of 0.015 m. For whatever change is used, the efficiency of the produced PV solar cells is not noticeably different. [ABSTRACT FROM AUTHOR]

Aluminum Matrix Composite (AMC) has the potential to be used in a wide range of industries, including the equipment industry, automobiles, aerospace, and so on. Because they provide benefits such as low weight, low production costs, corrosion resistance, faster assembly, and so on. Each reinforcement has distinct properties that, when combined, improve the properties of the base aluminum. By incorporating these types of reinforcement, the properties of AMC are improved over the traditional approach to materials engineering. According to reports, various materials such as SiC, Al2O3, and TiO2 are commonly used as conventional reinforcement on AMC, but the use of conventional reinforcement is costly in terms of production cost. The use of low-cost reinforcement, such as natural resources and agricultural waste, may lower AMC's overall cost while increasing its functionality in a variety of applications. Sea sand, red mud, aloe vera powder, bamboo leaf ash, and fly ash are examples of natural resources and agricultural waste that have been used as reinforcement in metal matrix composites. The addition of reinforcement improved the mechanical and physical properties of the materials. Furthermore, the use of natural resources and agricultural waste is friendly to the environment, renewable, biodegradable, and cost effective. According to this review paper, adding reinforced improved the mechanical properties of the material such as tensile strength, hardness, stiffness, and wear resistance. [ABSTRACT FROM AUTHOR]

Interface bonding was critical in allowing load transfer and distribution from the matrix to the reinforcement without failure. These bonds may form as a result of mutual dissolution or a reaction between the particulates and matrix metal. Strong bonds at the interface are important for good wetting. One of the techniques used to create a surface layer on reinforced particles in order to produce good wettability is electroless plating. This method is frequently used to coat reinforcing particles in mixed metal matrix composites (MMC). The co-deposition of substances or particulates in developing films has produced a new generation of electroless particles, many of which have excellent wear resistance, high hardness, brittleness, and corrosion resistance. As a result, electroless plating has found widespread application in the aerospace, automotive, electronic parts, and chemical industries. Furthermore, this process is frequently used because it is simple, used low temperature, not dependent on geometry of substrate and does not necessitate high costs. The current article focuses on the effect of electroless coating on interface and wettability in recent years. Previous research has demonstrated that the electroless coating process improves wettability. Where the reinforcing particles are evenly distributed. [ABSTRACT FROM AUTHOR]

This study aims to determine the influence of ovality on cold water pipes (CWP) of a floating Ocean Thermal Energy Conversion (OTEC) platform. The ultimate strength of the cylindrical shell is suspected to depend on the interaction between the specific factors of the basic geometry and the imperfection parameters. The parameter that may affect the reduction in load-carrying capacity is geometric imperfection, namely ovality. This flexible pipe takes advantage of the seawater temperature difference between the sea surface and a depth of 800 meters. In this case study, the CWP is a cylindrical pipe strengthened with a stringer stiffener and has an exterior ring stiffener structure. The behaviour of this CWP under bending load is relatively unexplored. The analysis was carried out on a 10 m diameter aluminum pipe following the results of previous studies with a length between stiffeners of 100 m. The scenario used in the loading is bending loading caused by the effects of ocean currents. The results show that the critical bending moment stress derived from linear and non-linear analysis decreases as the initial ovality amplitude increases. This reduction is almost 50% of the initial bending capacity value if the ovality reaches 10%. In addition, the prediction results from the analysis will be added to the initial study of the OTEC design in further studies. [ABSTRACT FROM AUTHOR]

Pre-impregnated materials (Prepregs) have greatly impacted many industries that require specific advanced composites, such as aerospace structures for UAVs. Prepreg material aids the structure by reducing weight while increasing strength and allowing for reasonably consistent manufacture. One of the most essential features of these materials is the variation in properties as the orientation of the layer changes. This requires the use of advanced techniques for strength analysis, including numerical modelling and material testing. This paper presents an experimental evaluation approach to estimate the mechanical properties of composite shells, including cutting schemes, specimen preparation, and test procedures. In the next stage, this study discusses the use of ABAQUS FEA to replicate the phenomenon of specimen failure modes. The investigated prepreg specimens in this study were created using XC 130 unidirectional easy composite prepreg. Through this research, the failure mode results of testing and numerical analysis showed a good agreement. [ABSTRACT FROM AUTHOR]

The development of unmanned aerial vehicles (UAVs) in this modern era is growing rapidly, starting from the design, structure, and security systems of the UAV itself. UAVs are starting to be widely used in everyday life and in military activities. A lot of research has been done to find the most optimal design for a UAV, especially in the military field which requires high precision and accuracy. In terms of structure, a lot of research has been done, from the material side to the reinforcing structure. The security system of a UAV is also very important so as not to endanger the community and reduce errors when a UAV is on a mission. The results of this article show how the development of the design, structure, and security system of a UAV. [ABSTRACT FROM AUTHOR]

This article provides a review of the wind turbines classification, and the latest status of the wind energy installed capacity globally. Globally many of the developed, and few developing countries have been in a good progression in terms of the wind installed capacity. As a continent of Africa, many of the installed wind capacity has been mainly in South Africa, Egypt, and Morocco. As a country, Tanzania has shown strong wind resources, but there has no much-installed wind capacity apart from the newest opened wind farm that produces 2.4 MW. According to the other studies at present, there have many plans for future wind projects that will make Tanzania be one of the largest wind energy producers around the continent. [ABSTRACT FROM AUTHOR]

The difficulty in controlling the proper bonding during manufacturing sandwich for ship structure is a major problem. One of the damage types that often occurs is debonding caused by the lack of the adhesive layer bond between the two faceplate materials and the sandwich core at the centre. Furthermore, the identification of damage in ship structure becomes essential to ensure the structural integrity and security issues. Based on the issues above, damage identification on the sandwich plate of Ferry Ro-Ro with several debonding ratios using the k-NN algorithm was proposed. The cross-validation method was used to check the validity of the proposed algorithm model in practice. The proposed models were analyzed with various k-fold values, k-NN values, and number of iterations to investigate the influence of the those parameters on the accuracy of the model. From the result, it can be found that increasing k-fold value is the best strategy to increase the accuracy of the model. However, increase number of neighbors (k) caused a bias so that the accuracy decreased. The tests resulted in the highest accuracy of 97.60% obtained at k-fold 11 with k=3 and 90 iterations. It can be summarized that the large number of k-folds and small k-NN parameters do not require large iterations to obtain high prediction results. [ABSTRACT FROM AUTHOR]

This paper presents the failure analysis of the rocker arm, which experienced abrasive wear failure. History and chronology will be given to identify what factors triggered the disappearance. Visual examination and micro-hardness Vickers tests have been carried out to collect evidence to prove the hypothesis. The design evaluation in stress and fatigue characteristic conditions has been simulated using FEM-based software. All data have been analyzed and then assembled into one complete story to conclude. This paper presents a detailed fractographic and stress study to assess the causes of failure. [ABSTRACT FROM AUTHOR]

The development of medical facilities is crucial in Indonesia's remote island since COVID-19-19 disease collapses the hospital system. This work is intended to develop the COVID-19 vessel as a medical support system with a dynamic positioning system to give medical health care for Indonesia's remote island. The COVID-19 vessel is named KM. LOTUS is arranged similarly with Type B medical facility standards. Conceptual design and performance calculation comprised weight calculation, medical facility arrangement, resistance and powering test, seakeeping performances are evaluated. The ship is equipped with an ambulance boat to increase mobility capabilities for smaller waters, such as narrow straits and estuaries. It is placed behind the ship, uses an autonomous system to climb up to the top of the deck. The resistance test has a value of 66.6 kN and a power of 383 HP at a ship speed of 12.22 knots. The seakeeping analysis was carried out using the strip theory method by simulating a ship speed of 12.22 knots representing Maluku sea condition. It can be found that different incoming waves will produce different oscillatory movements of heave, pitch, and roll. [ABSTRACT FROM AUTHOR]

The current work presents a partitioned tightly coupled fluid-structure interaction (FSI) simulation. Fluid-structure interaction is an important aspect, accurate prediction method for ship dynamics is a significant prerequisite for structural design and an essential consideration for strength evaluation. In a seaway, the ship structure flexes constantly. It is subjected to neither static nor quasi-static loads. As a result, a dynamic interaction between the hull reactions and the activities of the surrounding fluid, known as fluid-structure interaction, is always present. This study has several conclusions, including the FSI effect associated with the hydrodynamic recovery force may have the most significant impact on the structural dynamic response. The major influence of restoring forces affects both structural damages and absorbed energy. Because of the effect of hydrodynamic restoring forces, multiphysics simulations for typical passenger ship disaster scenarios showed that appropriate FSI modeling may be necessary for either collision or grounding. Then, the fluid motion was identified on the dynamic behavior of the struck plate of a fluid tank, subjected to wedge impacts. [ABSTRACT FROM AUTHOR]

Magnetorheological (MR) fluid is a smart material whose characteristics can be altered by arranging a magnetic field. When the MR fluid is affected by a magnetic field (on-state), the viscosity of the MR fluid will increase in a matter of milliseconds. When it is not affected by the magnetic field (off-state), the viscosity will decrease. The unique properties of the MR fluid are exploited in technology in the medical field as medical wearable rehabilitation and tactile feedback devices. In the rehabilitation of patients, the MR fluid is much applied to the device orthosis and prosthetics. Meanwhile, what is included in tactile feedback in the medical field are haptic devices. All three, orthosis, prosthetic, and the device haptic-based MR fluid, should have a compact and lightweight design so easy to install and does not interfere with the patient's mobility. Other parameters that must be considered are damping torque, energy use, process maintenance, response time, and working temperature. To fulfil these parameters, several designs have been made. Unfortunately, there are very few review articles regarding the use of MR fluid in the medical field. Therefore, this article provided an overview of various developments, latest designs, and applications of MR fluid as medical wearable rehabilitation and tactile feedback devices. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are an environmentally friendly energy source. One EV application uses Lithium-ion (Li-ion) battery cells. In practice, li-ion operation generates heat which will burden battery performance. Therefore, this review paper will discuss the battery thermal management system (BTMS). There are several methods of BTMS, but this paper review will only focus on air-cooled and liquid-cooled BTMS, where it is still rare to find a comparison of these two cooling methods. The goal is to know about the best cooling method. The results show that liquid-cooled BTMS is superior in uniform temperature distribution but is more complex, and fluid leakage can occur. In comparison, air-cooled BTMS has the advantage of a more accessible system, but the temperature distribution between batteries is less even. [ABSTRACT FROM AUTHOR]

Li-ion batteries have been widely used as an energy source in electronics and applications for electric vehicles. In accordance with the main function in the use of lithium-ion batteries (LIB) as the main energy storage resource needs attention. especially on battery safety issues in receiving external mechanical loads including such as mechanical deformation which allows the battery to be damaged and fail. Understanding the dynamic behavior that occurs in the battery is very important in analyzing battery performance according to the possible conditions that the battery receives. In this case, tests using drop test and quasi-static methods were carried out on the battery to evaluate the safety of electrical properties and battery safety. This article discusses the physical and mechanical characteristics of drop tests and quasi-static tests provide the basic understanding needed to design and analyze the results of drop tests and quasi-static tests on batteries. [ABSTRACT FROM AUTHOR]

Since the battery is the most crucial part of an electric vehicle, its safety level has attracted researchers. This work focused on the computational approach of several batteries using non-linear finite elements. The battery types simulated were Lithium-Iron-Phosphate (LFP) 18650, which were produced in a laboratory. A mechanical load simulation scenario follows a condition when an electric vehicle experiences a collision. Here, the battery pack was axially and laterally crushed. The simulation approach is carried out using the LS-DYNA software. The mechanical properties of the battery are obtained from several experimental approaches. Finally, the battery cell is crushed from the axial and lateral directions with a non-linear finite element approach based on the obtained mechanical properties. This parameter will be used in the future to predict the failure of the battery pack due to dynamic loads. [ABSTRACT FROM AUTHOR]

Conditions around the environment are crucial in the process of welding defects. Temperature, humidity, and air velocity are determinants of hydrogen rise. The formation of hydrogen in the air caused by unfavorable environment can cause defects in the welded joint. The more vapor in the air, the more hydrogen is formed. One welding defect caused by hydrogen content is porosity. Porosity is formed in aluminum welding due to the presence of hydrogen trapped in the Al weld metal. This study discusses welding protection involving experiments with variations in temperature of 20 ° C, 25 ° C, 30 ° C, variations in relative humidity of 65%, 72%, 80%, and air velocity of 1.5m/s; 1.7 m/s; 2.0 m/s so as to minimize porosity defects at the welding joint due to hydrogen. In research shows the lower the temperature, the lower the solubility of hydrogen, this happens because the solubility of hydrogen at low temperatures is very limited. While welding is carried out with a relatively high humidity level, the higher the hydrogen reserves. [ABSTRACT FROM AUTHOR]