Energy Release Research Articles

Three-dimensional buckling model reveals the evolution of energy-driven biofilm wrinkle morphologies

On solid substrates, biofilms develop rich wrinkle morphologies during its growth. Based on the thin film buckling theory, we established a local three-dimensional biofilm/substrate buckling model, and explored the effects of mechanical forces, elastic modulus of the substrate and biofilm thickness on the wrinkle morphology. We simulated the wrinkle evolution in various patterns of Bacillus subtilis biofilm growing on agar substrates with different stiffness and found that the biofilm wrinkling process is the process of internal energy release. The stiffness of the substrate changes the wrinkling time of the biofilm; The biofilm wrinkle morphology (patterns II, III, IV) Uinternal and Uinternal/U0 decrease with nutrient consumption, and the biofilm evolves towards lower energy consumption. In the early stages of biofilm growth (patterns I, II, and III), the harder the agar substrate, the larger the Ufriction and Ufriction/U0, which is less conducive to biofilm expansion.

Development and quench-training performance evaluation of the world’s largest aperture superconducting magnet with zero-evaporation for the SWORD

Abstract Mastering plasma–material interactions is critical for obtaining a high-performance and high-duty cycle fusion reactor. The requirements for the construction of a magnetized, steady-state, large-area, high-flux plasma generator necessitate the application of superconducting coils. At present, DIFFER’s main experiment, Magnum-PSl (MAgnetized plasma Generator and NUMerical modeling for Plasma Surface Interactions), stands as the world’s only facility capable of exposing materials to plasma conditions similar to those of future fusion reactors. This facility relies on a superconducting magnet system, which consists of five superconducting solenoids wound on a 2.5 m-long stainless-steel coil former. It can generate a magnetic field of 2.5 T, with a 1.01 m warm bore. ORNL’s main experiment, MPEX (The Materials Plasma Exposure eXperiment), is a superconducting linear plasma device consisting of six independent units. MPEX has developed a superconducting magnet system with warm bore diameters of either 0.65 m or 1.56 m, capable of operating at both 1.25 and 2.5 T. ASIPP’s main experiment, SWORD (Superconducting plasma Wall interactiOn lineaR Device), represents the world’s highest-parameter steady-state linear plasma generator, capable of producing plasma that closely resembles the boundary parameters of fusion reactors, primarily for materials research and lifetime testing. The device is equipped with a superconducting magnet with a magnetic field of 3 T, warm bore diameter of 1200 mm, and length of 2 m to ensure effective confinement of the high-performance plasma. This paper discusses key technical issues in the development of superconducting magnets for SWORD, including high-precision coil winding design, curing processes for large-diameter insulation materials, and stress distribution and regulation under high-current conditions. Additionally, the research details the establishment of an efficient cryogenic cooling system and a reliable energy release control method during quench-training tests, resulting in enhanced excitation performance and strategies for long-term stable operation of superconducting magnets in a zero-evaporation cryogenic system.

Experimental-simulation analysis on mechanical degradation and energy evolution characteristics of sandstone under water-rock coupling effects

With increasing coal mining depths, water-rock interactions exacerbate the mechanical degradation of coal-rock masses and geological disaster risks. Investigating the mechanical properties and energy evolution mechanisms of water-bearing sandstone is crucial for ensuring safe mining operations. To address the existing research gap in analyzing energy evolution mechanisms of water-saturated rock masses from a macroscopic perspective and the lack of exploration into energy mechanisms at critical failure points at the mesoscale, this study employs the particle discrete element software PFC3D to establish numerical models of sandstone with varying water contents. Combined with uniaxial compression tests and energy calculation principles, the mechanical degradation laws and energy evolution characteristics of sandstone under water-rock interactions are systematically investigated. The results indicate that the mechanical properties of sandstone exhibit significant degradation with prolonged immersion time, where compressive strength and elastic modulus gradually decrease with increasing water content. Energy evolution during sandstone deformation and failure can be divided into three stages: elastic energy storage, crack propagation energy dissipation, and sudden energy release at failure. Water immersion significantly reduces energy absorption efficiency during the elastic storage stage and increases energy dissipation rates during crack propagation. Mesoscale crack development analysis reveals that water accelerates the extension of initial fractures and the initiation of new cracks, while higher water content promotes a transition from localized to diffuse crack distribution. Additionally, the energy thresholds at critical failure points and failure modes of samples with different water contents show significant correlations, revealing the dynamic regulatory mechanism of water-induced weakening effects on energy accumulation and release in sandstone. These findings provide theoretical support for safe mining and dynamic disaster prevention in deep water-rich coal seams.

Driven two-fluid Alfvén waves in a solar magnetic flux tube with a realistic ionization rate

Context. This study was performed in the context of the chromosphere and low corona heating. Aims. We considered the evolution of driven Alfvén waves in the solar atmosphere, whose initial state was modeled with a realistic ionization profile. We discuss their potential role in plasma heating. Methods. Two- and half-dimensional (2.5 D) numerical simulations of the solar atmosphere were performed with the use of the code JOANNA. The dynamics of the atmosphere was described by the two-fluid equations (and ionization and recombination terms were taken into account) for ions (protons) combined with electrons and neutrals (hydrogen atoms). The initial atmosphere was described by a hydrostatic background supplemented by the Saha equation and embedded in a magnetic flux tube. This background was perturbed by a monochromatic driver that operated in the transversal components of the ion and neutral velocities. Results. We demonstrated that as a result of ion-neutral collisions, Alfvén waves are damped. The damping length grows with the wave period. This is anticipated based on the linear theory for a homogeneous medium. The developed flux-tube model results at higher temperatures rise for shorter periods of the driving wave, and the effect is stronger than for the pure hydrostatic state. Conclusions. We highlight the importance of taking the realistic background plasma into account in the evolution of two-fluid Alfvén waves that participate in the thermal energy release and in the heating in the solar chromosphere and low corona.

Spatiotemporal evolution of UV pulsations and their connection to 3D magnetic reconnection and particle acceleration

Quasi-periodic pulsations (QPPs) are a common feature of impulsive solar flare emissions, yet their driving mechanism(s) remain unresolved. Observational challenges such as image saturation during large flares, low image cadence, and limited spatial resolution often hinder our ability to study the spatiotemporal evolution of QPPs in detail. The M3.7 solar flare of February 24, 2023 produced long-period (3.4 min) QPPs in hard X-ray (HXR) and ultraviolet (UV) emissions and was associated with a large-scale asymmetric filament eruption. This study leverages the unique opportunity presented by the combination of a long pulsation period and the large spatial scale of the eruptive event. Our goal is to pinpoint the location of the observed QPPs within the flare structure, characterize their spatiotemporal evolution, examine their connection to particle acceleration, and understand their relationship to flare ribbon dynamics and the underlying magnetic reconnection geometry. The UV emissions of the flare ribbons were analyzed with SDO/AIA 1600 Å base-difference imaging, while the HXR emissions were studied with Solar Orbiter/STIX. The flare region was divided into four subregions focused on the main flare ribbons or filament footpoints in both polarities, from which the integrated light curves were extracted. Time-distance plots were constructed to follow the motion of the UV ribbon kernels and to relate them to the QPPs. A spectral fitting of the HXR observations was performed to characterize the accelerated electron populations and the HXR images were reconstructed to study the X-ray sources. We find that the strength and characteristics of the UV pulsations varied significantly across subregions, with the strongest correlation to HXR pulsations and the most complex spatiotemporal evolution occurring in the compact southern flare ribbon. In this location, UV pulsations originated from a sequence of UV kernels at an expanding flare ribbon front, accompanied by secondary motions along the front. In contrast, another expanding ribbon front, likely associated with a different subsystem of the reconnecting flux, did not exhibit pulsations. The UV pulsations spatially coincided with HXR sources, indicating non-thermal electrons as a common driver. The HXR spectrum exhibited a soft-hard-soft evolution, suggesting a modulation of the electron acceleration efficiency on the same timescale as the pulsations. Around the eastern filament anchor region, UV pulsations were produced instead by plasma injections into a separate filament channel, highlighting the presence of distinct emission sources beyond flare kernels. Our results suggest that the spatiotemporal evolution of the UV pulsations is largely driven by the propagation of magnetic reconnection, including slipping reconnection, within an asymmetric magnetic geometry. We further hypothesise that slipping reconnection, combined with the structure of the quasi-separatrix layers (QSLs), plays a key role in the generation and propagation of UV kernels. An additional time-varying reconnection process was potentially required to fully explain the observations. Our findings emphasize the importance of spatially resolved QPP studies on the timescales of energy release to disentangle different emission processes and their connection to magnetic reconnection.

Advanced Ignition and Combustion Analysis of Second‐Generation Biodiesels in Turbocharged Diesel Engines

ABSTRACTThis study investigates the energy release characteristics of second‐generation biodiesel blends derived from beef tallow and castor bean in a turbocharged compression ignition engine. The primary objective was to evaluate ignition delay, combustion phasing, and energy release rates at various engine loads using blends of B10 and B20 biodiesel concentrations. A comprehensive experimental setup, including a diesel engine and a detailed thermodynamic model, was employed for this analysis. Dynamometric testing was conducted to assess the performance of the biodiesel blends compared to mineral diesel and soybean biodiesel. Key parameters such as cetane number, viscosity, and fatty acid composition of the biodiesels were correlated with their combustion behavior. Energy release characteristics were measured under low (250 kPa), medium (500 kPa), and high (750 kPa) load conditions. The study revealed that beef tallow biodiesel advanced ignition timing, reducing premixed combustion phases across all loads. At low load, castor bean biodiesel showed significant ignition delays (around 3° crank angle longer than diesel), leading to higher peak energy release rates, notably at high loads where it surpassed mineral diesel. The B20 blend of castor bean biodiesel emitted 320 mg/kg of unburned hydrocarbons at low load, compared to 21 mg/kg for diesel, indicating challenges in achieving complete combustion. Beef tallow biodiesel exhibited favorable ignition characteristics, while castor bean biodiesel faced issues with delayed ignition and higher energy release rates due to its high viscosity and low cetane number. Optimizing the molecular composition of castor bean biodiesel and exploring advanced fuel injection strategies could enhance its combustion efficiency. Further research is recommended to investigate the long‐term effects on engine wear and emissions, ensuring these biodiesels' viability as sustainable alternatives to conventional fuels.

Influence of Geometric Non-Linearities on the Mixed-Mode Decomposition in Asymmetric DCB Samples

The Asymmetric Double Cantilever Beam (ADCB) is a common test configuration used to produce mixed mode I/II in composite materials. It consists of two sublaminates with different thicknesses or elastic properties, a situation that usually occurs in bimaterial adhesive joints. During this test, the sample undergoes rotation. In this work, the influence of this rotation on the calculation of the energy release rate (ERR) in modes I and II was studied using the Finite Element Method (FEM). Several models with different degrees of asymmetry (different thickness ratio and/or elastic modulus ratio) and different applied displacements were prepared to obtain different levels of rotation during the test. As is known, the concept of modes I and II refers to the components of the energy release rate calculated in the direction perpendicular and tangential to the delamination plane, respectively. If the model experiences significant rotation during the application of the load, this non-linearity must be considered in the calculation of the mode partition I/II. In this work, appreciable differences were observed in the values of modes I and II, depending on their calculation in a global system or a local system that rotates with the sample. When performing crack growth calculations, the difference between critical loads can be in the order of 4%, while the difference between mode I and mode II results can reach 4% and 14%, respectively, for an applied displacement of only 5 mm. Currently, this correction is not usually implemented in Finite Element calculation codes or in analytical developments. The purpose of this article is to draw attention to this aspect when the rotation of the specimen is not negligible.

Fast Degradation of Solid Electrolyte in Initial Cycling Processes, Tracked in 3D by Synchrotron X-ray Computed Tomography.

Solid-state lithium batteries are developing rapidly as a promising next-generation battery, while challenges still persist in understanding their degradation processes during cycling due to the difficulties in characterization. In this study, the 3D morphological evolution of the Li3PS4 solid electrolyte was tracked during electrochemical cycles (plating and stripping) until short circuit by utilizing in situ synchrotron X-ray computed tomography with sufficient spatial and temporal resolution. During the degradation process, cracks in the electrolyte alternately generated from the two electrode/electrolyte interfaces and propagated until shorting. The lithium dendrites filled in the electrolyte cracks but had a greatly reduced filling ratio after the first plating stage; therefore, the cell could continue working for some time after the solid electrolyte was fully fractured by cracks. The compression of the two lithium electrodes mainly occurred in initial cycles where a ca. 4-7 μm reduction in thickness was observed. The mechanical force and electric potential fields were modeled to visualize their redistributions in different stages of cycling. The release of strain energy after the first penetration and thereafter the subsequent driving forces are discussed. These results reveal a fast degradation of solid electrolyte in the initial cycles, providing insights for further modifications and improvements in solid-state batteries.

Inequalities of energy release rates in compression of nanoporous materials predict its imminent breakdown

Inequalities of energy release rates in compression of nanoporous materials predict its imminent breakdown

Experimental Investigation of a Passive Compliant Torsional Suspension for Curved-Spoke Wheel Stair Climbing

Curved-spoke wheels have been proposed as an effective way to overcome stair-like obstacles with smooth, rotation-only motion. However, when the wheel’s contact point shifts, discontinuous changes in its radius of curvature cause abrupt drops in the robot’s linear speed, often leading to reduced payload stability and slip. As a result, maintaining reliable stair climbing becomes more difficult. At higher speeds, these sudden changes become stronger, further reducing dynamic stability. To address these issues, we propose a passive Compliant Spiral Torsional Suspension (C-STS) attached to the wheel’s drive axis. Through camera-based marker tracking, we analyzed wheel trajectories under various stiffness and speed conditions. In particular, we define the deceleration caused by the velocity drop during contact transitions as our dynamic stability metric and demonstrate that the C-STS significantly reduces this deceleration across low-, medium-, and high-speed climbing, based on comparisons both with and without the suspension. It also raises the average velocity, likely due to a brief release of stored elastic energy, and lowers the net torque requirement. Our findings show that the proposed C-STS greatly improves dynamic stability and suggest its potential for enhancing stair-climbing performance in curved-wheel-based robotic systems. Furthermore, our approach may extend to other reconfigurable wheels facing similar instabilities.

Discovery of Evolution of the Temporal Features of X-Ray Bursts from SGR J1935+2154

Abstract SGR J1935+2154 has undergone eight active episodes since its discovery in 2014. In this study, our focus is on the evolution of the temporal characteristics including burst duration, minimum variation timescale (MVT), and waiting time across these active episodes observed by Fermi/Gamma-ray Burst Monitor (GBM). We find a linear increase in the logarithmic mean of burst duration over time, with a deviation during the fourth and eighth active episodes containing X-ray burst (XRB)−Fast Radio Burst (FRB) 200428 and XRB−radio burst 221021 association events. We also find a possible increasing burst frequency, with the fourth active episode exhibiting an exceptionally high burst rate. Therefore, XRB−FRB 200428 is potentially triggered by energetic events such as a large crust, magnetic reconnection, or glitches. The MVT analysis reveals deviations in the sixth and seventh active episodes with ∼3σ. These results may suggest evolving magnetospheric field geometry, neutron star crust, and energy release mechanisms of SGR J1935+2154. Finally, our findings predict that longer XRB durations indicate the highly likely occurrence of XRB and radio burst association events, warranting focused multiwavelength observations during such episodes, which will also be further confirmed or disproved by future observations.

Investigating the Influence of Axial Velocity and Tangential Velocity on Combustion Characteristics in a Cylindrical Vortex Combustor

Efficient combustion is essential for various applications, including gas turbines, industrial furnaces, and propulsion systems. The interaction between axial and tangential velocities significantly influences combustion stability, flame shape, and pollutant formation. However, a comprehensive understanding of these effects in a cylindrical vortex combustor remains elusive. The primary of this study is to analyse how axial and tangential velocities impact combustion characteristics within the Cylindrical Vortex Combustor (CVC). Specifically, we aim to determine the optimal velocity combination that ensures stable combustion, minimal emissions, and efficient energy release. The CVC geometry was modelled, and the simulations were conducted for various axial and tangential velocity combinations by Computational Fluid Dynamics (CFD) simulations using ANSYS Fluent software were employed to explore the behaviour of the vortex combustor under varying conditions. The Navier-Stokes equations, energy equation, and species transport equations were solved. Air inlet conditions included a mass flow rate of 40 mg/s and for fuel inlet was set 3.0 to 4.0 mg/s through an equivalence ratio (j) ranging from 0.5 to 1.5. The numerical findings indicate higher axial velocities enhance mixing and promote stable combustion and this velocity component excessive lead to flame blowout. The tangential velocities influence vortex strength and flame stability and will enhances recirculation and flame anchoring. Due to these conditions, an optimal balance between axial and tangential velocities yields efficient combustion. Understanding the interplay between axial and tangential velocities is essential for designing efficient vortex combustors. The findings provide valuable insights for optimizing combustion systems, reducing emissions, and improving overall performance.

Hamiltonian energy and coexistence of spiral wave patterns in lattice array from bidirectional coupled neurons

Abstract In this study, we explore a Hindmarsh–Rose model to evaluate the impacts of asymmetric coupling, mutual interference, and external magnetic flux, as these factors play crucial roles in neurons dynamics. The performance of these networks is largely dependent on the coupling between neural oscillators. The entire neuron model’s dynamical behavior is altered when an electrical synapse connection has an asymmetric coupling. More complicated behaviors will be displayed by neuron models exposed to magnetic flux induction with such asymmetric synaptic coupling. As a result, we provide a coupled neuron model that takes into account asymmetric electrical synapses and flux coupling. The different dynamic features of the coupled Hindmarsh–Rose neuron model are investigated by taking the coupling, diffusion, and flux coupling coefficients constant into performance as the control factors. We have demonstrated that the integration of magnetic flux that enters the neuronal model can significantly attenuate spiral wave activity within the network. This approach mitigates the propagation of these waves and enhances the stability of the neural network. The supply and release of energy are significant for the functioning of individual neurons and neural networks. This paper investigates the Hamiltonian energy of neurons under electromagnetic induction, offering new insights into the interaction between neuronal dynamics and external electromagnetic fields.

ANTIMATTER: THE POTENTIAL IMPACT ON THE FUTURE OF MEDICAL AND PHARMACEUTICAL INDUSTRIES

Antimatter comprises antiparticles that mirror ordinary matter in mass but exhibit inverted quantum properties, such as charge. Theoretical predictions by Paul Dirac in 1928 laid the groundwork for its discovery, which Carl Anderson achieved experimentally in 1932 through positron detection in cosmic ray studies. Subsequent discoveries of antiprotons and antineutrons further solidified the concept of antimatter. Antimatter is produced in high-energy particle accelerators, cosmic ray interactions with Earth's atmosphere, and certain types of radioactive decay. Particle accelerators, such as linear accelerators, cyclotrons, synchrotrons, betatrons, Cockcroft-Walton generators and Van de Graaff generators, play a crucial role in antimatter production and research. This property makes antimatter both a potential energy source and a subject of safety concerns due to the immense energy release upon annihilation. Storing antimatter safely involves sophisticated techniques like magnetic traps, magnetic bottles and electrostatic traps, which prevent antimatter from coming into contact with matter. The study of antimatter also addresses fundamental questions in physics, such as the matter-antimatter asymmetry in the universe. Despite the challenges in production, storage, and handling, ongoing research aims to unlock the secrets of antimatter and harness its potential for scientific and practical advancements. This review highlights the history, production methods, potential applications and challenges associated with antimatter, emphasizing its significance in both fundamental research and potential technological innovations. Peer Review History: Received 13 February 2025; Reviewed 12 March 2025; Accepted 14 April; Available online 15 May 2025

A Theoretical Kinetic Study of Nitrocyclohexane Combustion: Thermal Decomposition Behavior and H-Atom Abstraction.

Nitrocyclohexane (NCH) is regarded as a highly promising energetic liquid fuel and additive for pulse detonation engines (PDEs) due to its excellent ignition performance and rapid energy release characteristics. Developing a detailed kinetic model for NCH is crucial for understanding its combustion characteristics and accurately predicting its behavior under actual operating conditions. In this study, reactive molecular dynamics (RMD) simulations were performed employing the ReaxFF-lg force field and the canonical (NVT) ensemble to investigate the temperature-dependent kinetic behavior of NCH. The results indicate that the initial decomposition of NCH is primarily driven by C-N bond rupture, followed by C-H bond cleavage, H atom abstraction, and other reactions, with H-abstraction playing a more significant role at lower temperatures. Subsequently, a systematic investigation of H-abstraction at seven sites in NCH involving six small species (Ḣ, ȮH, ĊN, HȮ2, NO2, and O2) was conducted at the QCISD(T)/cc-pVXZ(X = D,T)//MP2/cc-pVXZ (X = D,T,Q)//M06-2X/6-311++G(d,p) level of theory. The calculations reveal that there are minimal differences in reactivity between axial and equatorial H-abstraction, which proceed as parallel reaction channels. Compared to H-abstraction at nitro-substituted, meta, and para positions on the NCH ring, ortho H-abstraction reactions exhibit relatively lower rate coefficients. The obtained kinetic parameters in Arrhenius form and thermodynamic data in NASA polynomial format, covering a wide temperature range (298.15-2000 K), can be directly utilized for the development of the NCH kinetic mechanism.

Single Cu Atoms Anchored Energetic COFs as Combustion Catalytic Promoters toward Rapid and Concentrated Thermal Decomposition of Ammonium Perchlorate.

Achieving a synergistic, rapid, and concentrated energy release process of ammonium perchlorate (AP) is of vital significance for boosting the thrust of composite solid propellants. However, conventional catalytic promoters often exhibit suboptimal catalytic kinetics due to inefficient utilization of active sites. Herein, atomically dispersed Cu-coordinated covalent organic frameworks (COFs)-based catalytic promoters are reported, decorating with energetic anion groups. The highly accessible single Cu sites confined in the COFs significantly contribute to the raid and concentrated energy release of AP, yielding a sharply narrowed decomposition peak at 341.3°C with a peak width of only 9°C. This performance is markedly superior to the dispersed exothermic process of raw AP (410.3°C with a peak width of 30°C). Additionally, the energetic COF promoter considerably increased the output energy via collaboratively promoting the chemical energy release of AP and its own decomposition. Correlating in situ spectroscopies and theoretical calculations reveals that the incorporated anionic groups effectively modulate the local electronic structure of the Cu sites. This alteration promotes the key step of cleavage of Cl─O bonds in AP intermediates to produce reactive oxygen species and also boosts the oxidation of NH3 to high-valence nitrogen oxides, thereby accelerating the combustion reaction kinetic.

Energy release and related sensitivity analysis of anisotropic CJBs under compression conditions without and with lateral pressure

Energy release and related sensitivity analysis of anisotropic CJBs under compression conditions without and with lateral pressure

Thermal Stability Difference between NQ and NOG: Insights from Pyrolysis Reactions via First-Principles Molecular Dynamic and Quantum Chemistry Modeling.

The thermal stability differences between NQ and NOG were investigated by examining their initial decomposition mechanisms at both the molecular and crystalline scales using density functional theory calculations. First-principles molecular dynamics simulations revealed that NQ primarily undergoes intermolecular hydrogen or oxygen atom transfer reactions, while NOG preferentially decomposes through a ring-opening reaction. Analysis of decomposition product evolution demonstrated that NQ decomposes faster at high temperatures, with the decomposition products of both compounds being strongly dependent on their molecular structures. Quantum chemistry calculations showed that NOG molecules exhibit higher energy barriers for the same unimolecular decomposition pathways compared to NQ. Furthermore, two reversible reactions, hydrogen transfer and bond rotation, were identified as key factors enhancing NOG's thermal stability. These findings significantly advance our understanding of structure-property relationships in energetic materials while providing valuable insights into studying energy release mechanisms and designing novel energetic compounds.

Quasiperiodic Slow-propagating Extreme-ultraviolet “Wave” Trains after the Filament Eruption

Abstract The eruption of the filament/flux rope generates the coronal perturbations, which further form extreme-ultraviolet (EUV) waves. There are two types of EUV waves, namely, fast-mode magnetosonic waves and slow waves. In this Letter, we first report an event showing the quasiperiodic slow-propagating (QSP) EUV “wave” trains during an M6.4-class flare (SOL2023-02-25T18:40), using multiple observations from Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA), Chinese Hα Solar Explorer (CHASE)/Hα Imaging Spectrograph (HIS), Advanced Space-based Solar Observatory (ASO-S)/Full-disk vector MagnetoGraph (FMG), SUTRI, and Large Angle and Spectrometric Coronagraph (LASCO)/C2. The QSP “wave” trains occurred as the filament showed a rapid rise. The QSP “wave” trains have the projected speeds of 50–130 km s−1 on the plane of the sky, which is slower than the fast-mode magnetosonic speed in the solar corona. And the calculated period of the QSP wave trains is 117.9 s, which is in good agreement with the associated flare quasiperiodic pulsation (140.3 s). The QSP wave trains could be observed during the entire impulsive phase of the flare and lasted about 30 minutes in the field of view (FOV) of SDO/AIA. About 30 minutes later, they appeared in the FOV of LASCO/C2 and propagated to the northwest. We suggest that the QSP wave trains are probably apparent waves that are caused by the successive stretching of the inclined field lines overlying the eruptive filament. The periodic pattern of the QSP wave trains may be related to the intermittent energy release during the flare.

Approximate Formulas for the Energy Release Rate of a Crack Perpendicular to a Material Interface

Approximate Formulas for the Energy Release Rate of a Crack Perpendicular to a Material Interface