Core Energy Research Articles

Design and matching control strategy of electro-hydraulic load-sensitive hydraulic power unit for legged robots

A hydraulic power unit is the core energy source of hydraulic legged robots, ensuring the robot's maneuverability and carrying capacity in complex terrains. However, its pressure and flow output are usually set to a fixed level under all working conditions, which leads to mismatched pressure and flow requirements of hydraulic drive units. This mismatch reduces the stability and control accuracy of the hydraulic drive units and results in significant energy waste. To address these issues, this paper proposes an electro-hydraulic load-sensitive hydraulic power unit and a matching control strategy to better align outputs with requirements, thereby enhancing energy efficiency. Firstly, with the variable speed servo motor driving axial piston pump as the core, the closed system working principle of an electro-hydraulic load-sensitive hydraulic power unit is proposed, and the mathematical model of key components exhibiting strong nonlinearity and time-varying parameters is derived. After that, a matching control strategy based on flow feedforward and pressure difference compensation feedback is proposed. Finally, simulations and experiments are conducted to verify the feasibility of the unit and its matching control strategy. This paper provides a new solution for the design and control of hydraulic power units, laying the groundwork for achieving high-performance hydraulic systems.

Controlling clouds-to-scars dislocations' transitions on spherical crystal shells

The closed topology of spherical crystals renders the presence of topological defects inevitable. These defects can organize in a plethora of different structures, such as “clouds” or grain boundary “scars”, challenging for theoretical modeling and experimental visualization. Visualizing the defects by fluorescent dye adsorption, we reveal ion concentration control of a clouds-to-scars transition, which we attribute to commonly neglected defects' core energy. The consequent line tension energy probes the defects' molecular scale energetics, enabling pattern tuning for future applications. Published by the American Physical Society 2024

Characterization of fuel cladding chemical interaction on a high burnup U-10Zr metallic fuel via electron energy loss spectroscopy enhanced by machine learning

Fuel cladding chemical interaction (FCCI) is one of the limiting factors for metallic fuels in nuclear application. A comprehensive analysis of chemical elements in FCCI is the basis for understanding the phenomena and developing potential mitigating strategies. The detection of low atomic number elements (Z < 11) and lanthanide fission products is challenging for energy dispersive x-ray spectroscopy (EDS). This work used scanning transmission electron microscopy (STEM) based electron energy loss spectroscopy (EELS) to study the distribution of carbon and lanthanides in the FCCI region of a solid U-10Zr (wt%) fuel irradiated to 13.2 at. % burnup at fast flux testing facility. Processing the EELS data involved three major steps: 1) enhancing the signal to noise ratio by denoising the spectrum using principal component analysis methods; 2) identification of chemical elements with core energy loss edges; 3) microstructural phase segmentation based on raw EELS spectrums using the K-means clustering method. EELS analysis revealed the formation of zirconium carbide, a rind-like microstructural phase in FCCI region between fuel and cladding. This rind appeared to be intact at this burnup. The study also revealed the shift of plasmon peak between zirconium and zirconium carbide. The EELS mapping also indicated a different distribution of Ce from other lanthanide elements, such as La, Pr, and Nd, suggesting the lanthanides should be separately investigated. The use of the K-means clustering method on the EELS data of FCCI region revealed different phases, especially Fe-Ce and Zr-C, that concurred with the findings from EDS and STEM-EELS elemental mappings.

Role of glucose in regulating menstrual cycle

Goal of the study: To find correlation between estrogen hormone and glucose intake. Introduction: The main estrogens: estradiol, estrone and their acyl-esters have been studied essentially related to their classical estrogenic functions. However their main effect in the body is probably the sustained control of core energy metabolism. With regard to energy, the estrogen molecular species act through control of glucose availability. Material and methods: There were analyzed articles from the PubMed database, from the last 5 years 2019-2024, mentioning such words as “estrogen”, “glucose”, “ menstrual cycle” [1]. Results: Estrogens play a paramount and continued regulatory role, to maintain energy (lipid / glucose) homeostasis. Estrogens have extensive and powerful control of energy homeostasis. Premenopausal women exhibit enhanced insulin sensitivity and reduced incidence of type 2 diabetes, compared with age matched men, but this advantage disappears after menopause with disrupted glucose homeostasis, in part owing to a reduction in circulating 17 β –estradiol (E2). Moreover a study shows the efficacy of a glucagon like peptide-1 and estrogen dual agonist (GLP1-E2) in pancreatic islet protection. The enzymes that are involved in the menstrual cycle are β-glucoronidase, thought to be involved in the final stages of mucopolysaccharide breakdown. Conclusion: So far there is limited information on the major role played by different forms of physiological estrogens in the control of energy metabolism at the whole body level. E2 protects the functionality of the pancreatic β cells, preventing apoptosis, adapting their function to insulin resistance and maintaining their insulin content. The lack of E2 availability also increases hepatic insulin clearance. Estrogen receptor α plays a crucial role in regulating glucose. However, the underlying mechanisms remain incompletely understood and therefore studies on the maintenance of (lipid / glucose) homeostasis are ongoing [2-10] in various neuro-endocrine and visceral multisystem biomedical areas, where the diagnostic role of markers is essential [11,12].

Non-linear effects of three core mineral resources, energy uncertainty, and inclusive digitalization on economic growth: A comparative analysis of US and China

This study examines the asymmetric effects of mineral resources (oil, coal, and gas), digitalization, and energy uncertainty on economic growth in China and the USA. Using quarterly data from 2000 to 2022, we employ the nonlinear autoregressive distributed lag (NARDL) model to analyze these relationships. The study begins by conducting unit root tests, cointegration analysis, and asymmetry tests to establish robust connections between the variables. The long- and short-run results confirm the presence of asymmetry, as positive and negative shocks in oil rents, digitalization, and energy uncertainty affect economic growth differently. Notably, positive shocks in oil rents and digitalization favour economic growth, indicating that increases in oil rents and digital inclusion contribute to economic development. Conversely, positive shocks in energy uncertainty tend to reduce economic growth. Interestingly, the findings for China and the USA show similar asymmetric patterns; coal and natural gas rents positively influence economic growth, while the control variables suggest that capital and labour increase contribute to both countries' development. The error correction terms, 0.731 (73.1%) for China and 0.625 (62.5%) for the USA, indicate the annual rate at which asymmetric discrepancies are corrected. All diagnostic tests confirm the suitability of the NARDL model for this study. Finally, the study reveals significant bi-directional causality among all pairs of variables.

The formation and post-formation processes of vortex rings discharged from laminar starting jets

Motivated by biological systems, vortex rings can enhance the propulsive efficiency in industrial systems. To study the vortex properties during the formation and post-formation stages, impulsively starting jets are investigated by simulations. The effects of the stroke ratio and nozzle geometry are studied at a fixed jet Reynolds number of 2500. The stroke ratio at the formation number is found to be not enough to produce a vortex ring with maximum circulation. The stroke ratio is suggested to be about twice as large as the formation number. An alternative criterion based on the circulation ratio is proposed to describe the onset of pinch-off. This criterion states that the pinch-off would start when the vortex ring attains about 80% of the total jet circulation. During the formation stage, the scaling laws for vortex trajectories and circulation are proposed for continuous formation. By combining the suggested scaling relations and Saffman's velocity formula, the evolution of non-dimensional energy can be predicted. During the post-formation stage, the scaling laws for vortex properties (e.g., the vortex ring diameter, translational velocity, and circulation) are found to be independent of both the nozzle configuration and the vortex Reynolds number. On the grounds of the invariance of impulse in vortex decay, the scaling laws of vortex motion are derived for the non-dimensional energy, circulation, and diffusivity scale of the vortex core. In consequence, the normalized energy and circulation found in experiments can be successfully derived from the similarity model for both nozzle configurations.

Forecasting wind turbine blade waste with material composition and geographical distribution: Methodology and application to Germany

Wind energy has become a key player in global electricity generation. The management of end-of-life (EoL) wind turbine blade (WTB) material streams is a challenge that requires urgent attention. The aim of this study was to forecast the future EoL WTB material, composition and geographical distribution of decommissioned on- and offshore wind turbines in Germany. Based on the German core energy market data register and a review of forecasting methods, a hybrid approach was developed that combines a statistical, deterministic and stochastic model with three scenarios to assume the service life of wind turbines in operation. This method was applied to Germany to estimate the mass of WTBs until 2050. The results show that a total EoL WTB material mass of 698 kt is expected, consisting of 492 kt of glass fibre reinforced polymer WTBs and 206 kt of hybrid WTB material with a carbon fibre reinforced polymer mass share of approximately 12.4 kt. From 2024 onwards, a displacement of 64.4 km in the centre of gravity of the expected EoL WTB material stream towards the north-west coast of Germany could be observed. The authors demonstrate the novelty of the method and findings in relation to circular economy paths of EoL WTB material.

Realizing enhanced energy storage performance of Na0.47Bi0.47Ba0.06TiO3-based relaxors with weak coupling behavior by manipulating phase fraction

Lead-free dielectric capacitors have attracted considerable attention as the core energy storage element of pulsed power systems due to their advantages of fast charging capability, high power density and environmental friendliness. However, the low recoverable energy storage density (Wrec) and narrow operating temperature range have become the bottleneck technical problems limiting its practical application. In this work, a class of weakly coupled relaxor ferroelectrics with excellent Wrec (9.06 J/cm3) and energy storage efficiency (η ∼ 85.3 %) were designed and prepared by manipulating phase fraction. Moreover, the materials exhibit excellent temperature stability with regard to energy storage, with a change in Wrec and η of less than 8 % over a wide temperature range (25 °C − 200 °C). The introduction of Sm(Mg0.5Hf0.5)O3 (SMH) enhances the insulating properties while refining the grains, effectively increasing the breakdown field strength (Eb) of the material. The emergence of weakly coupled nano-microdomains has the effect of suppressing the nonlinear polarization response of the material, which in turn results in a high polarization difference (ΔP). The preceding work presents a universal strategy for the future design and preparation of BNT-based lead-free dielectric capacitors with high energy storage properties (ESP) and good temperature stability.

A Comparative Blast Mitigation Performance Evaluation of Metallic Sandwich Panels with Honeycomb, Corrugated, Auxetic, and Foam Cores

Due to the high energy absorption capability and excellent bending strength of the sandwich panels, they are mostly preferred as protective structures against explosive blast attacks. The evaluation of their blast-mitigation characteristics through experiments is highly dangerous, costly, time-consuming, and polluting for the environment. Therefore, in this presented work, a series of numerical analyses were performed to evaluate the blast mitigation of the outstanding sandwich panels with honeycomb, corrugated, auxetic, and foam cores. The masses of sandwich panels were kept constant, and their areal densities were maintained constant throughout the study to effectively compare their performance under identical air blast loading conditions. To apply the air blast loads to the designed sandwiches, 1–3[Formula: see text]kg of spherical-shaped trinitrotoluene charges were used for a 100[Formula: see text]mm stand-off distance. The sandwiches are made of high-strength AL-6XN steel and crushable aluminum foam. The rate-dependent Johnson–Cook constitutive model of plasticity and the crushable foam model with volumetric hardening were used for the evaluation of sandwich panels’ plastic deformations. The findings of the work depicted that the honeycomb core is more efficient than the other core structures of the same masses because the sandwich panels with honeycomb core provide smaller back skin deflections, globalized core crushing, and higher core energy absorption than the other sandwich panels for extreme conditions of air blast loading.

Metabolic adaptation pilots the differentiation of human hematopoietic cells.

A continuous supply of energy is an essential prerequisite for survival and represents the highest priority for the cell. We hypothesize that cell differentiation is a process of optimization of energy flow in a changing environment through phenotypic adaptation. The mechanistic basis of this hypothesis is provided by the established link between core energy metabolism and epigenetic covalent modifications of chromatin. This theory predicts that early metabolic perturbations impact subsequent differentiation. To test this, we induced transient metabolic perturbations in undifferentiated human hematopoietic cells using pharmacological inhibitors targeting key metabolic reactions. We recorded changes in chromatin structure and gene expression, as well as phenotypic alterations by single-cell ATAC and RNA sequencing, time-lapse microscopy, and flow cytometry. Our observations suggest that these metabolic perturbations are shortly followed by alterations in chromatin structure, leading to changes in gene expression. We also show that these transient fluctuations alter the differentiation potential of the cells.

Effect of morphology modulation and interface engineering of SnS-MoS2 heterojunction on nonlinear optical response

MoS2 base films with different morphologies were prepared by modulating the magnetron sputtering parameters, and the base films were used to induce the growth of SnS with different structures, forming columnar and worm-like SnS-MoS2 heterojunctions, which were found to have excellent nonlinear absorption properties and their properties could be modulated by the morphology of the films by Z-scanning tests. The tunable morphology and crystalline quality of the films were characterized using scanning electron microscopy, atomic force microscopy and X-ray diffraction techniques and explained using the Stranski-Krastanow growth mechanism. The Raman spectrum of the heterojunction shows the A1g vibrational peak at 320 cm−1 and the appearance of Sn4+ in the X-ray photoelectron spectroscopy confirms the existence of S-Sn-S charge transfer channels between the interfaces. The fine spectra of all the elements in the X-ray photoelectron spectroscopy data as well as the characteristic absorption peaks in the absorption spectra confirm the formation of heterojunctions, and the constructed heterojunctions are determined to be type-II heterojunctions using the method of the core energy level. Heterojunction was determined to be a type-II heterojunction by using the core energy level method. The photoluminescence peak quenching of the heterojunction indicates that there is a process of charge transfer between the interfaces, and the type-II heterostructure of SnS-MoS2 makes the nonlinear absorption performance in the 800 nm band regulated by the morphology of the material. The nonlinear optical absorption coefficient is two orders of magnitude higher than that of the pure materials, and the nonlinear absorption performance of the worm-like SnS-MoS2 heterojunction is superior to that of the columnar SnS-MoS2 heterojunction, which is attributed to the larger interfacial contact area, the better crystalline quality, and the more efficient carrier interfacial transport capability. These tunable type-II SnS-MoS2 heterojunctions with ultrafast nonlinear optical absorption have a positive impact on practical applications such as optical limiter devices and all-optical switching devices.

Effectiveness of Vortioxetine for the Treatment of Emotional Blunting in Patients with Major Depressive Disorder Experiencing Inadequate Response to SSRI/SNRI Monotherapy in Spain: Results from the COMPLETE Study.

The multinational, open-label COMPLETE study (NCT03835715) investigated the effectiveness of vortioxetine in alleviating emotional blunting in patients with major depressive disorder (MDD) experiencing inadequate response and emotional blunting while being treated with a selective serotonin reuptake inhibitor (SSRI) or serotonin-noradrenaline reuptake inhibitor (SNRI). This paper presents results for the subgroup of patients enrolled in Spain. Patients with MDD (n = 67) experiencing partial response and emotional blunting during monotherapy with an SSRI or SNRI were switched to vortioxetine (10-20 mg/day) for 8 weeks. The primary study outcome was emotional blunting, assessed by the Oxford Depression Questionnaire (ODQ). After 8 weeks of vortioxetine, the mean (SE) change in ODQ total score from baseline was -26.0 (2.9) (P < 0.001). Respective changes in Montgomery-Åsberg Depression Rating Scale (MADRS), Motivation and Energy Inventory, Digit Symbol Substitution Test, and Sheehan Disability Scale (SDS) total scores were -14.9 (0.8), +34.2 (4.5), +6.3 (1.6), and ‒9.0 (1.3) (all P < 0.001 vs baseline). At week 8, 70.4% of patients no longer reported emotional blunting and 53.7% had achieved remission from their depressive symptoms (defined as a MADRS total score ≤10). Mediation analysis showed 77.1% of the change in SDS total score to be a direct effect of the improvement in ODQ total score after switching to vortioxetine. Adverse events were reported by 35 patients (52.2%), most commonly nausea (14 patients, 20.9%). At week 8, 33/54 patients (61.1%) were receiving vortioxetine 20 mg/day. In this study investigating the effectiveness of vortioxetine in Spanish patients with MDD who experienced inadequate response and emotional blunting on SSRI/SNRI monotherapy, significant improvements in emotional blunting, core depressive symptoms (including anhedonia), sleep duration, motivation and energy, cognitive performance, and overall patient functioning were observed during the 8 weeks of treatment. Two-thirds of patients no longer reported emotional blunting and over half were in remission from their depressive symptoms at week 8.

Research on key factors of pulsed CO2 laser annealing of Ge core fiber

The germanium (Ge) core fiber with a core diameter of 29–32 μm and a cladding diameter of 158–162 μm was annealed by pulsed CO2 laser, exploring the key factors determining the properties of annealed Ge core fiber. The experimental results shown that the single pulse energy and the laser scanning speed are key factors of pulsed CO2 laser annealing of Ge core fibers. The reasons for experimental results were preliminarily analyzed from the perspectives of Ge atomic instantaneous kinetic energy and temperature field of Ge core during annealing. For different frequencies of laser annealing, optimal samples with similar properties can be obtained by adjusting the single pulse energy and laser scanning speed. For the samples annealed by 30 kHz, 50 kHz, 60 kHz, and 70 kHz lasers, the optimal Raman frequency average value is 301.191 cm−1, 301.107 cm−1, 301.153 cm−1, and 301.174 cm−1; the lowest propagation loss is 2.174 dB/cm, 2.596 dB/cm, 2.387 dB/cm, and 2.312 dB/cm respectively, which were measured using a quantum cascade laser with the wavelength range from 4.7 to 4.9 μm.

A DFT/MRCI Hamiltonian parameterized using only ab initio data: I. valence excited states

A new combined density functional theory and multi-reference configuration interaction (DFT/MRCI) Hamiltonian parameterized solely using the benchmark ab initio vertical excitation energies obtained from the QUEST databases is presented. This new formulation differs from all previous versions of the method in that the choice of the underlying exchange–correlation (XC) functional employed to construct the one-particle (orbital) basis is considered, and a new XC functional, QTP17, is chosen for its ability to generate a balanced description of core and valence vertical excitation energies. The ability of the new DFT/MRCI Hamiltonian, termed QE8, to furnish accurate excitation energies is confirmed using benchmark quantum chemistry computations, and a mean absolute error of 0.16 eV is determined for the wide range of electronic excitations included in the validation dataset. In particular, the QE8 Hamiltonian dramatically improves the performance of DFT/MRCI for doubly excited states. The performance of fast approximate DFT/MRCI methods, p-DFT/MRCI and DFT/MRCI(2), is also evaluated using the QE8 Hamiltonian, and they are found to yield excitation energies in quantitative agreement with the parent DFT/MRCI method, with the two methods exhibiting a mean difference of 0.01 eV with respect to DFT/MRCI over the entire benchmark set.

The C1s core levels of polycyclic aromatic hydrocarbons and styrenic polymers: A first-principles study.

Understanding core level shifts in aromatic compounds is crucial for the correct interpretation of x-ray photoelectron spectroscopy (XPS) of polycyclic aromatic hydrocarbons (PAHs), including acenes, as well as of styrenic polymers, which are increasingly relevant for the microelectronic industry, among other applications. The effect of delocalization through π aromatic systems on the stabilization of valence molecular orbitals has been widely investigated in the past. However, little has been reported on the impact on the deeper C1s core energy levels. In this work, we use first-principles calculations at the level of many body perturbation theory to compute the C1s binding energies of several aromatic systems. We report a C1s red shift in PAHs and acenes of increasing size, both in the gas phase and in the molecular crystal. C1s red shifts are also calculated for stacked benzene and naphthalene pairs at decreasing intermolecular distances. A C1s red shift is in addition found between oligomers of poly(p-hydroxystyrene) and polystyrene of increasing length, which we attribute to ring-ring interactions between the side-chains. The predicted shifts are larger than common instrumental errors and could, therefore, be detected in XPS experiments.

The Impact-driven Atmospheric Loss of Super-Earths around Different Spectral Types of Host Stars

A planet’s mass loss is important for the its formation and evolution. The radius valley (RV) is believed to be triggered by evaporation-induced mass loss. As an alternative mechanism for RV, the mass loss of post-impact planets is thoroughly investigated in this work. The impact energy is converted to the planet’s internal energy, enhancing its core energy and accelerating mass loss and orbital migration. As the host star changes from K type to F type, the planet’s mass loss and orbital migration increase. When the initial gas-to-core-mass ratio is small, the migration efficiency for planets around K-type stars will increase, which helps to suppress mass loss and retain the planet’s mass and radius within a specific range. On the contrary, planets around more massive F-type stars experience more substantial mass loss, potentially leading to complete mass loss, and migrate to orbits with longer periods. Our calculation shows that planets around different spectral types of host stars give rise to an RV ranging from 1.3 to 2.0 R ⊕, consistent with the observed range of 1.3–2.6 R ⊕. Despite the presence of uncertain parameters, the planetesimal impact can promote the RV establishment for planets around host stars of different spectral types.

Methods to estimate body temperature and energy expenditure dynamics in fed and fasted laboratory mice: effects of sleep deprivation and light exposure

Monitoring body temperature and energy expenditure in freely-moving laboratory mice remains a powerful methodology used widely across a variety of disciplines–including circadian biology, sleep research, metabolic phenotyping, and the study of body temperature regulation. Some of the most pronounced changes in body temperature are observed when small heterothermic species reduce their body temperature during daily torpor. Daily torpor is an energy saving strategy characterized by dramatic reductions in body temperature employed by mice and other species when challenged to meet energetic demands. Typical measurements used to describe daily torpor are the measurement of core body temperature and energy expenditure. These approaches can have drawbacks and developing alternatives for these techniques provides options that can be beneficial both from an animal-welfare and study-complexity perspective. First, this paper presents and assesses a method to estimate core body temperature based on measurements of subcutaneous body temperature, and second, a separate approach to better estimate energy expenditure during daily torpor based on core body temperature. Third, the effects of light exposure during the habitual dark phase and sleep deprivation during the light period on body temperature dynamics were tested preliminary in fed and fasted mice. Together, the here-published approaches and datasets can be used in the future to assess body temperature and metabolism in freely-moving laboratory mice.

Moment tensor potential for static and dynamic investigations of screw dislocations in bcc Nb

A new machine-learning interatomic potential, specifically a moment tensor potential (MTP), is developed for the study of screw-dislocation properties in body-centered-cubic (bcc) Nb in the thermally- and stress-assisted temperature regime. Importantly, configurations with straight screw dislocations and with kink pairs are included in the training set. The resulting MTP reproduces with near density-functional theory (DFT) accuracy a broad range of physical properties of bcc Nb, in particular, the Peierls barrier and the compact screw-dislocation core structure. Moreover, it accurately reproduces the energy of the easy core and the twinning-anti-twinning asymmetry of the critical resolved shear stress (CRSS). Thereby, the developed MTP enables large-scale molecular dynamics simulations with near DFT accuracy of properties such as for example the Peierls stress, the critical waiting time for the onset of screw dislocation movement, atomic trajectories of screw dislocation migration, as well as the temperature dependence of the CRSS. A critical assessment of previous results obtained with classical embedded atom method potentials thus becomes possible.

Intrinsic factors responsible for brittle versus ductile nature of refractory high-entropy alloys

Refractory high-entropy alloys (RHEAs) are of interest for ultrahigh-temperature applications. To overcome their drawbacks — low-temperature brittleness and poor creep strength at high temperatures — improved fundamental understanding is needed. Using experiments, theory, and modeling, we investigated prototypical body-centered cubic (BCC) RHEAs, TiZrHfNbTa and VNbMoTaW. The former is compressible to 77 K, whereas the latter is not below 298 K. Hexagonal close-packed (HCP) elements in TiZrHfNbTa lower its dislocation core energy, increase lattice distortion, and lower its shear modulus relative to VNbMoTaW whose elements are all BCC. Screw dislocations dominate TiZrHfNbTa plasticity, but equal numbers of edges and screws exist in VNbTaMoW. Dislocation cores are compact in VNbTaMoW and extended in TiZrHfNbTa, and different macroscopic slip planes are activated in the two RHEAs, which we attribute to the concentration of HCP elements. Our findings demonstrate how ductility and strength can be controlled through the ratio of HCP to BCC elements in RHEAs.

Dynamic modeling and experimental study of multi-coil composite core energy harvester

To improve the output performance and working bandwidth of the magnetic levitation energy harvester, a new structure of multi-coil composite core energy harvester was proposed and verified by numerical simulation and experiment. Firstly, the working mechanism of the energy harvester was analyzed. The dynamics model and COMSOL Multiphysics finite element analysis model were established to study the influence of magnetic field and coil position on the output characteristics of the energy harvester. Then, an experimental platform was built to verify the proposed new energy harvester, and the influence of coil position on the output power of the energy harvester was explored. Three kinds of coil thicknesses, two kinds of coil winding directions, six kinds of coil connection modes and two kinds of magnet distribution experiments were designed. Finally, the influence of suspended core mass on output performance was analyzed, and the energy harvester with or without magnetic liquid was tested by sweeping frequency to evaluate its output performance. The experimental results show that the magnetic field near the coil can be enhanced effectively, and the output performance of the whole system can be improved by the magnet mutual repulsion energy harvester with coil connection mode CM1 in a consistent coil direction. With the increase of composite core mass, the output voltage and power of the energy harvester also increase, but the peak frequency decreases. Compared with the energy harvester without magnetic liquid, the output power performance of the designed multi-coil composite core energy harvester is significantly improved by 29%, and the frequency bandwidth growth rate is 73%. The normalized power density can reach 134.26 μWcm−3g−2. The new structure of the multi-coil composite core provides important reference significance for designing a more efficient magnetic levitation energy harvester.