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In this paper, a heat generator with fluid agitation is developed and experimentally studied. This heat generator can convert kinetic energy from a wind turbine directly to thermal energy through the process of viscous dissipation—a process achieved through the agitation of the working fluid inside a container. In the experimental study, an electric motor (instead of a wind turbine) was used to provide the kinetic energy input to the heat generator. The torque, rotational speed, and temperature rise in the fluid were measured. Using the measured quantities, the efficiency of kinetic energy to sensible heat conversion was calculated. Experiments were conducted to investigate the effects of different impellers, rotational speeds, and working fluids, including distilled water, ethylene glycol (EG), and their respective nanofluids, with A l 2 O 3 nanoparticles at different concentrations. The study also found that the temperature rise in fluids due to viscous dissipation was influenced by the specific heat of the fluid, suggesting that the heat generator can be optimized for energy storage with high-specific-heat fluids, such as water, or for achieving a higher temperature rise with low-specific-heat fluids, such as ethylene glycol. The experimental results indicated that the heat generator was up to 90% efficient in converting kinetic energy to thermal energy. The study revealed that, for constant power input, the heat dissipation rate depends solely on the vessel's geometry, not the fluid properties. Optimizing the impeller design and baffles within the vessel is crucial for maximizing power input. For applications, a wind turbine can power this heat generator to provide heat to a house or a commercial building. [ABSTRACT FROM AUTHOR]

Energy harvesting from Vortex-Induced Vibration (VIV) presents a promising avenue for renewable energy generation by harnessing the kinetic energy of fluid flows through innovative technologies. Despite the increasing interest in VIV energy harvesting, there is a need for a systematic evaluation of the existing literature to understand the research trends, key contributors and emerging areas of focus. A bibliometric analysis offers a quantitative approach to address this gap, providing valuable insights into the evolution and dynamics of research on energy harvesting from VIV. The analysis employs VOSviewer software to analyze publication data retrieved from Scopus, focusing on publication trends, top authors, subject area, top citation, popular keywords, co-authorship countries’ collaboration and network mapping based on citation by country. By examining publication patterns, citation counts and collaboration networks, this study aims to uncover underlying patterns and identify critical factors driving research in this field. The bibliometric analysis reveals a significant upward trend in research activity, with a notable increase in publications from recent years, indicating growing interest and recognition of VIV energy harvesting. In conclusion, this bibliometric analysis provides valuable insights into the research trends, key contributors and collaborative networks in energy harvesting from VIV. The findings guide for both academic and industrial , facilitating informed decision-making and driving progress toward sustainable energy solutions. This study also lays the groundwork for future research directions and interdisciplinary collaborations aimed at maximizing the potential of VIV energy harvesting for renewable energy generation.

In this paper, a heat generator with fluid agitation is developed and experimentally studied. This heat generator can convert kinetic energy from a wind turbine directly to thermal energy through the process of viscous dissipation—a process achieved through the agitation of the working fluid inside a container. In the experimental study, an electric motor (instead of a wind turbine) was used to provide the kinetic energy input to the heat generator. The torque, rotational speed, and temperature rise in the fluid were measured. Using the measured quantities, the efficiency of kinetic energy to sensible heat conversion was calculated. Experiments were conducted to investigate the effects of different impellers, rotational speeds, and working fluids, including distilled water, ethylene glycol (EG), and their respective nanofluids, with Al2O3 nanoparticles at different concentrations. The study also found that the temperature rise in fluids due to viscous dissipation was influenced by the specific heat of the fluid, suggesting that the heat generator can be optimized for energy storage with high-specific-heat fluids, such as water, or for achieving a higher temperature rise with low-specific-heat fluids, such as ethylene glycol. The experimental results indicated that the heat generator was up to 90% efficient in converting kinetic energy to thermal energy. The study revealed that, for constant power input, the heat dissipation rate depends solely on the vessel’s geometry, not the fluid properties. Optimizing the impeller design and baffles within the vessel is crucial for maximizing power input. For applications, a wind turbine can power this heat generator to provide heat to a house or a commercial building.

Energy harvesting from Vortex-Induced Vibration (VIV) presents a promising avenue for renewable energy generation by harnessing the kinetic energy of fluid flows through innovative technologies. Despite the increasing interest in VIV energy harvesting, there is a need for a systematic evaluation of the existing literature to understand the research trends, key contributors and emerging areas of focus. A bibliometric analysis offers a quantitative approach to address this gap, providing valuable insights into the evolution and dynamics of research on energy harvesting from VIV. The analysis employs VOSviewer software to analyze publication data retrieved from Scopus, focusing on publication trends, top authors, subject area, top citation, popular keywords, co-authorship countries' collaboration and network mapping based on citation by country. By examining publication patterns, citation counts and collaboration networks, this study aims to uncover underlying patterns and identify critical factors driving research in this field. The bibliometric analysis reveals a significant upward trend in research activity, with a notable increase in publications from recent years, indicating growing interest and recognition of VIV energy harvesting. In conclusion, this bibliometric analysis provides valuable insights into the research trends, key contributors and collaborative networks in energy harvesting from VIV. The findings guide for both academic and industrial, facilitating informed decision-making and driving progress toward sustainable energy solutions. This study also lays the groundwork for future research directions and interdisciplinary collaborations aimed at maximizing the potential of VIV energy harvesting for renewable energy generation. [ABSTRACT FROM AUTHOR]

Although the El Niño-Southern Oscillation (ENSO) affects West Antarctica via teleconnection, it is delayed by a season, because the Amundsen Sea Low (ASL) anomaly in response to the ENSO is the strongest in May. However, the process and mechanism of the delay has not been fully elucidated yet. In this study, we examined the formation of the ENSO-driven teleconnection in each month from January to May by analyzing the kinetic energy conversion and Rossby wave propagation. The flow perturbed by the ENSO gains energy from the basic state by energy conversion, but the perturbation does not reach the high latitudes until April. In May, although the ENSO intensity becomes weak, the development of the subtropical jet induces waves to propagate further south, resulting in the anticyclonic circulation anomaly over the ASL region. Numerical experiments that account for the decay of the ENSO forcing and the monthly varying basic state also indicate that the formation of the teleconnection is the strongest in May. The results reveal that the configuration of the basic state is crucial for the teleconnection in response to the ENSO to reach West Antarctica.

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With the rapid development of digital technology, the global economy has begun to move towards the digital economy era, and China has proposed a new infrastructure strategy in response to the demand for production activities in the digital era. Combining the background of the new infrastructure, this article conducts an in-depth analysis and exploration of the innovative mode of industrial enterprise operation, production management methods, etc., and summarizes the key characteristics of the digital transformation of industrial enterprises under the background of the new infrastructure. Based on this, it reveals the mechanism and logic of the new infrastructure to drive the digital transformation of industrial enterprises, and finds that with the development of new infrastructure, its impact on the digital transformation of industrial enterprises evolves from the empowering stage to the enabling stage. Furthermore, through the analysis of key channels, it finds that digital R&D and simulation design, advanced manufacturing and smart production, user value capture and demand forecasting constitute important channels for new infrastructure to empower enterprises to digitally transform; customer value re-creation, value realization method transformation, and innovation ecological circle construction link plays an important role in the new infrastructure to enable the digital transformation of industrial enterprises. [ABSTRACT FROM AUTHOR]

In this study, a novel small‐scale electromagnetic energy harvester is designed and optimised, which aims at addressing the limitations of existing approaches in output power scavenged from low‐velocity flowing water. Instead of conventional cantilever beams, an asymmetric arc‐shaped elastic beam is implemented to disrupt flow, leading to its oscillation in the induced unsteady flow field. An electromagnetic transducer is utilised to convert kinetic energy into electrical energy. Furthermore, the effects of the structure asymmetry and curvature on the electrical outputs are investigated to optimise the scavenging energy capability. A prototype with the volume of 152.4 cm3 is fabricated and tested. A maximum open‐circuit voltage of 1440 mV is obtained at 0.409 m/s, and the harvester generates an output power of 0.503 mW when it is connected to an external load of 110 Ω. The small‐scale harvester shows great potential for applying in wireless sensor networks. [ABSTRACT FROM AUTHOR]

This study developed an energy converter composed of an eccentric rotor and a circular Halbach-array magnetic disk to convert the energy created by the rolling motion of a sailing boat into electrical energy. The proposed eccentric rotor was expected to be capable of converting reciprocating rolling motion into a rotational hula-hoop motion when equipped with an appropriate weighted block. The eccentric rotor revolving in a hula-hoop motion enhances power generation because the angular velocity is higher than that provided by small-amplitude oscillation. The rolling frequencies and angles for hula-hoop motion occurrence correspond with the main frequencies and amplitudes obtained from the spectrum analysis of the rolling-motion signal of a 700-ton sailing boat. Comprehensive dynamic analysis of the proposed energy converter was conducted to characterize the relationships between the various parameters and the probability of hula-hoop motion occurrence. An approximate solution was derived according to the numerical results, and the corresponding stability analysis was evaluated using the homotopy perturbation method and the Floquet theory to create an occurrence criteria map for hula-hoop motion. The magnetic flux density and electromagnetic damping of the circular Halbach-array magnetic disk were evaluated using magnetic field strength simulation and Faraday׳s law of induction. A rolling motion emulator was constructed to verify the performance of the energy converter. The output power of a 6.25-kg prototype connected to an external load of 300 Ω in series was 1.37 mW at a rolling frequency of 0.30 Hz and a rolling angle of 10°. A large version of the proposed energy converter can be applied as a backup power source for a sailing boat, and a small version can be used as a power source for self-powered sensors installed on a boat. [ABSTRACT FROM AUTHOR]

In order to investigate the conversion of kinetic energy from a synoptic scale disturbance (SSD; period⩽seven days) to a low-frequency fluctuation (LFF; period>seven days), the budget equation of the LFF kinetic energy is derived. The energy conversion is then calculated and analyzed for the summers of 1997 and 1999. The results show that the energy conversion from the SSD to the LFF is obviously enhanced in the middle and lower troposphere during the heavy rainfall, suggesting this to be one of mechanisms inducing the heavy rainfall, although the local LFF kinetic energy may not be enhanced. [ABSTRACT FROM AUTHOR]

This paper describes the rationale and the engineering approach adopted for the development of technology for converting the kinetic energy in marine currents for large-scale electricity generation. Although the basic principles involved are relatively straightforward and well understood, being similar to those of a wind turbine, a practical and cost-effective large-scale system designed to extract the kinetic energy of flowing water has yet to be developed. This paper describes the research and development being undertaken through an industrial consortium with the aim of achieving this goal for the first time, i.e. to achieve the world's first commercially viable systems for delivering power from marine currents. [ABSTRACT FROM AUTHOR]