Article
Chemistry, Physical
Wei Zhong, Bingang Xu, Yuanyuan Gao
Summary: The engraved patterned spacer triboelectric nanogenerator (EPS-TENG) eliminates the need for third-party spacers or substrate deformation by using engraved pattern spacers that can elastically deform and recover automatically, adapting well to external periodic mechanical impacts. With a peak power of 92.34 μW and an average power of 8.48 μW, the EPS-TENG shows great potential for applications in harvesting mechanical energy from the environment and serves as a useful reference for similar research on engraved spacer triboelectric nanogenerators.
Article
Instruments & Instrumentation
Ganggang Liang, Daoli Zhao, Zhimiao Yan, Weipeng Sun, Zhemin Wang, Ting Tan
Summary: This study introduces a non-contact-type triboelectric nanogenerator (TENG) aimed at significantly enhancing its durability in harvesting low-frequency vibration energy. The proposed TENG utilizes permanent magnets and rolling-balls to increase anti-wear capability and improve efficiency. It achieves stable electrical output and can harvest energy from various human motions.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Engineering, Electrical & Electronic
Ahmed Haroun, Chengkuo Lee
Summary: Dielectric elastomers are effective ambient motion energy harvesters, and their coupling with a triboelectric nanogenerator can amplify the electrical output. By analyzing the coupled system and identifying optimal conditions, the maximum output yield can be realized.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Energy & Fuels
Orkhan Gulahmadov, Mustafa B. Muradov, Jiseok Kim
Summary: This study introduces a Scotch yoke-based triboelectric nanogenerator (TENG) system that harnesses wind power. The system converts the rotational motion of propeller blades into linear reciprocating motion, enabling the TENG pairs to operate in the contact-and-separation mode with a strong compressing force. The electrical output of the system increases linearly with the number of TENG pairs.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Physical
Yurun Chen, Hu Zhang, Caihua Xu, Long Deng, Qiliang Yang, Haitao Zhang, Jianchun Xing, Liqiang Xie
Summary: In this study, a solid-ferrofluid triboelectric nanogenerator (SF-TENG) was proposed for ultra-low-frequency vibration energy harvesting. By optimizing the volume of ferrofluid and the magnetic field intensity, the performance of SF-TENG was enhanced resulting in an output power of 18.2 nW and charging a 1μF capacitor to 1.5 V in 150 s.
Article
Chemistry, Physical
Dandan Wang, Zhaoqi Liu, Xuanyi Dong, Dandan Zhang, Xiangyu Chen
Summary: Dielectric elastomer is a new intelligent soft material, but its driving voltage limits the portability and wearability. Triboelectric nanogenerator provides a feasible power supply solution for dielectric elastomer actuator. This review summarizes the development, mechanisms, material structures and performance of triboelectric nanogenerator powered dielectric elastomer actuator in various applications.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Shuo Chen, Yifan Guo, Lijie Sun, Wei Sun, Rasoul Esmaeely Neisiany, Kris Chen, Qingbao Guan, Zhengwei You
Summary: This study develops completely sustainable triboelectric nanogenerators (TENGs) using bio-based materials, green synthesis, and recycling techniques. The TENGs are fabricated with hierarchical porous structures through a salt-assisted 3D printing strategy, resulting in excellent electrical output performance. The discarded TENGs can degrade under benign conditions without negative impact on the environment.
SCIENCE CHINA-MATERIALS
(2023)
Article
Chemistry, Physical
Hongchun Luo, Jiayi Liu, Tao Yang, Yongqi Zhang, Qingjie Cao
Summary: This study proposes a dipteran flight-inspired bistable triboelectric nanogenerator (DFIB-TENG) for harvesting low-frequency vibration energy. Experimental results show that the DFIB-TENG has high energy output in a specific range of excitation frequency, amplitude, and link length.
Article
Engineering, Mechanical
Zewei Ren, Ziming Wang, Fan Wang, Site Li, Zhong Lin Wang
Summary: This study investigates the vibration behavior and excitation mechanism of an ultra-stretchable electrode film in wind energy harvesting. By developing perforations on the electrode film for geometric optimization based on aerodynamic characteristics, the output power of the TENG device has been significantly improved.
EXTREME MECHANICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Marcos Duque, Gonzalo Murillo
Summary: In this article, a triboelectric nanogenerator (TENG) has been developed to harvest mechanical energy from human motion and convert it into electrical energy. The energy generation has been optimized through material selection, design improvement, and charge injection. The TENG is capable of collecting mechanical energy from hand tapping and using it to power miniaturized electronic sensors in a self-sufficient and sustainable way.
Article
Chemistry, Multidisciplinary
Zhaoqi Liu, Shuyao Li, Shiquan Lin, Yuxiang Shi, Peng Yang, Xiangyu Chen, Zhong Lin Wang
Summary: This study reveals that strain and low temperature can induce crystallization behavior in elastic triboelectric materials, leading to a shift in triboelectric series and electrification polarity. Natural rubber exhibits a significant effect, and an applied strain at low temperature can further enhance this shift.
Article
Engineering, Environmental
Jia Xin Liu, Guoxu Liu, Zi Hao Guo, Weiguo Hu, Chi Zhang, Xiong Pu
Summary: This work presents a stretchable electret-based triboelectric nano-generator (SEB-TENG) for stretchable and wearable electronics. The device exhibits high stretchability, high charge density, and can be used to power electronic devices. A power management module (PMM) is also designed to optimize energy utilization.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Hao Lu, Wenyu Zhao, Zhong Lin Wang, Xia Cao
Summary: This paper introduces a biocompatible and degradable sugar triboelectric nanogenerator (S-TENG) that utilizes the physical property of sugar for energy converting application, with a simple structure. The S-TENG has high output power density, capable of powering LEDs and electronic sensors, as well as detecting the humidity and purity of the filled sugar.
Article
Chemistry, Physical
Dongguo Tan, Jiaxi Zhou, Kai Wang, Xuhui Zhao, Qiang Wang, Daolin Xu
Summary: Triboelectric nanogenerators (TENGs) are promising devices for converting low-frequency vibration energy into electrical energy efficiently. The bow-type TENG, with bistable stiffness feature, successfully solves the challenge of harvesting energy from low-frequency ambient vibrations.
Article
Chemistry, Multidisciplinary
Yang Yu, Qi Gao, Xiaosong Zhang, Da Zhao, Xiao Xia, Jianlong Wang, Hengyu Li, Zhong Lin Wang, Tinghai Cheng
Summary: To address the durability issue of triboelectric nanogenerators (TENGs), a rolling rod/ball design is proposed to reduce surface wear. However, the line/point contact significantly decreases the charge generation capability. Therefore, a contact-sliding-separation motion strategy is developed to achieve a TENG with high output performance and remarkable durability.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Engineering, Mechanical
The Hung Tran, Masayuki Anyoji, Takuji Nakashima, Keigo Shimizu, Anh Dinh Le
Summary: This study experimentally measured the skin friction around a 1/2-scale Ahmed body under different cross-wind conditions. The results showed that the flow on the slant surface was not significantly affected by the cross-wind condition for yaw angles below 3 deg, but was highly affected for yaw angles above 3 deg, leading to a dramatic increase in the drag of the model.
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Mathematics, Interdisciplinary Applications
Taiga Kanehira, Mark L. McAllister, Samuel Draycott, Takuji Nakashima, David M. Ingram, Ton S. van den Bremer, Hidemi Mutsuda
Summary: This paper investigates the effect of smoothing length on simulated wave breaking. The results suggest that a smoothing length in the range of 1.7 to 2 best reproduces the observed wave breaking phenomena in experiments.
COMPUTATIONAL PARTICLE MECHANICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Yusuke Nakamura, Takuji Nakashima, Chao Yan, Keigo Shimizu, Takenori Hiraoka, Hidemi Mutsuda, Taiga Kanehira, Takahide Nouzawa
Summary: This study identifies wake vortices associated with a significant aerodynamic drag increase in a simplified notchback car model. It clarifies the changes in the wake vortices and identifies four vortices near the region where the surface pressure of the base decreases. These vortices contribute to the drag increase and will be useful in the suppression of significant aerodynamic drag increase at specific yaw angles.
JOURNAL OF VISUALIZATION
(2022)
Article
Environmental Sciences
Minmo Chen, Aruni Dinan Hanifa, Naokazu Taniguchi, Hidemi Mutsuda, Xiaohua Zhu, Zenan Zhu, Chuanzheng Zhang, Ju Lin, Arata Kaneko
Summary: This study investigates the propagation and generation characteristics of M-2 and M-4 tidal currents in the Neko-Seto Channel using acoustic tomography. The results reveal the existence of nonlinear processes and asymmetries in tidal currents.
Article
Green & Sustainable Science & Technology
Ede Mehta Wardhana, Hidemi Mutsuda, Yoshikazu Tanaka, Takuji Nakashima, Taiga Kanehira, Shuhei Maeda, Masaaki Yamauchi
Summary: This study proposed a multi-layered TEG model and combined it with a PEG to form a PEG-TEG hybrid harvester, demonstrating improved output voltage by modifying key factors. The experiment showed that the multi-layered TEG can enhance electrical energy output in a smaller device, with vibration amplitude affecting electrical performance and key factors playing a significant role in energy generation.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Environmental Sciences
Naokazu Taniguchi, Yuji Sakuno, Haoran Sun, Shilin Song, Hiromori Shimabukuro, Masakazu Hori
Summary: This study used satellite data to investigate the spatiotemporal variation of floating macroalgae distribution around Japan from 2018 to 2021. The results showed that the coverage of floating macroalgae varies spatially and seasonally, with peak values occurring in the spring and summer in the southwestern area.
Article
Computer Science, Interdisciplinary Applications
Qingyu Wang, Takuji Nakashima, Chenguang Lai, Bo Hu, Xinru Du, Zhongzheng Fu, Taiga Kanehira, Yasufumi Konishi, Hiroyuki Okuizumi, Hidemi Mutsuda
Summary: The study proposes an enhanced multi-point infill criterion called PEHVInne, which improves the convergence efficiency of multi-objective optimization problems by adding a relatively large number of points in each cycle. The criterion considers both the potential for improvement of an evaluation point and the crowding distances between this point and its nearest-neighbor Pareto front points. Experimental results show that the proposed criterion enhances the efficiency and convergence of the optimization process for most benchmarks.
JOURNAL OF COMPUTATIONAL SCIENCE
(2022)
Article
Engineering, Mechanical
The Hung Tran, Masato Hijikuro, Masayuki Anyoji, Takanori Uchida, Takuji Nakashima, Keigo Shimizu
Summary: This study investigates the effects of short automatic moving deflectors (AMD) on the aerodynamic characteristics of the Ahmed body. The experimental results show that a short deflector can increase the drag of the model at low Reynolds numbers, but it becomes effective in reducing drag at high velocities, with a maximum drag reduction of 11%. The deflectors also significantly reduce the lift coefficient, up to 89%. Detailed analysis is conducted on the surface flow, pressure distribution, and flow on the symmetric vertical plane.
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2023)
Article
Green & Sustainable Science & Technology
Xinru Du, Hidemi Mutsuda, Yoshikazu Tanaka, Takuji Nakashima, Taiga Kanehira, Naokazu Taniguchi, Yasuo Moriyama
Summary: This study presents a flexible piezoelectric device (FPED) for ocean energy harvesting, which aims to provide continuous and stable energy supply for fish aggregating devices (FADs) and islands. The effectiveness and feasibility of the device are confirmed through experiments, theoretical models, and computational models.
ENERGY FOR SUSTAINABLE DEVELOPMENT
(2022)
Article
Environmental Sciences
Naokazu Taniguchi, Hidemi Mutsuda, Masazumi Arai, Yuji Sakuno, Kunihiro Hamada, Toshiyuki Takahashi, Kengo Yoshiki, Hironori Yamamoto
Summary: Reciprocal acoustic transmission and coastal acoustic tomography (CAT) is a powerful tool for measuring tidal currents in shallow coastal water. In this study, EnKF is applied to assimilate the path-averaged currents obtained from a reciprocal acoustic transmission experiment, resulting in improved velocity reconstruction and additional improvements through covariance inflation.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Dimas Angga Fakhri Muzhoffar, Yuji Sakuno, Naokazu Taniguchi, Kunihiro Hamada, Hiromori Shimabukuro, Masakazu Hori
Summary: Extensive floating macroalgae from the East China Sea have drifted to Japan's offshore area, and field observation is not sufficient to track their spatial and temporal changes. High-spatial-resolution satellite data with multiple spectral bands have improved remote sensing analysis. This study proposes an adaptive thresholding method using Sentinel-2 satellite data to detect floating macroalgae. By comparing different methods, the most advantageous approach for automatic detection of floating macroalgae using NDVI, NDWI, and FAI images is determined. The spatial coverage and reproducible combination for automatic detection of floating macroalgae in Kagoshima, Japan are examined.
Article
Thermodynamics
The Hung Tran, Masato Hijikuro, Masayuki Anyoji, Takanori Uchida, Takuji Nakashima, Keigo Shimizu
Summary: This study investigated the surface flow and aerodynamic characteristics of a 7/10 scale Ahmed model with deflectors at different angles. Luminescent oil film skin-friction measurement technique was used to study the flow fields on the slant and base surfaces. The results showed that higher deflection angles resulted in a sudden drop in drag and lift, with a maximum drag reduction of 8% at a deflection angle of 0 degrees.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2023)
Article
Engineering, Marine
Xinru Du, Hidemi Mutsuda, Yuya Wasada, Takuji Nakashima
Summary: Frictional drag reduction (DR) can save fuel in marine vehicle propulsion. This study introduces a novel numerical model that combines mesoscopic method with computational fluid dynamics (CFD) techniques, and validates the model using direct numerical simulation (DNS) and large eddy simulation (LES) methods. The model investigates the influence of polymer region height on non-uniform polymer DR and reveals significant DR efficiency even when the polymer region does not extend across the entire fluid area. This model lays the foundation for further research on polymer coatings DR and energy conservation of vessels.