Kinetic Energy Transfer Research Articles

Exploration of the form factors of turbulence kinetic energy transfer for shear exfoliation of graphene

Mass production of defect-free and large-lateral-size 2D materials via cost-effective methods is very important. Recently, shear exfoliation has shown great promise for large-scale production due to its simple operation, environmental-benignity and wide adaptability. However, a long-standing challenge is that with the production of more nanosheets, a ceiling yield and shattered products are encountered, which significantly limits their wider application. The method and efficiency of energy transfer in fluid is undoubtedly the key point in determining exfoliation efficiency, yet its in-depth mechanism has not yet been described. Thus, a thorough investigation of turbulence energy transfer is critically necessary. Herein, we identify two main factors that critically determine the exfoliation yield and provide a statistical analysis of the relationship between these factors and the exfoliation yield. In the initial shearing process, the coexistence of the 2D nanosheets and raw particles is the dominant factor; as time passes, the dimensional change of raw materials gradually has a greater influence on the energy transfer. These factors together lead to attenuated efficiency and a power function relationship between yield and exfoliation time. This investigation gives a statistical explanation of shear exfoliation technology for 2D material preparation and provides valuable insights for mechanical exfoliating high-quality 2D materials.

Heat Transfer Enhancement and Vortex Flow Structure in the Spirally Fluted Tubes

The turbulence kinetic energy and heat transfer performance of air in spirally fluted tube were numerically studied at a constant wall temperature with Reynolds number (Re) between 5000 and 45 000. Furthermore, the flow dynamics and heat transfer performance of spirally fluted tubes with five different geometric parameters as well as the effects of separation vortex and swirling wake flow on heat transfer and flow resistance were analyzed. According to the results, heat transfer is enhanced mainly because the fluid hit the windward side of the flute, thus generating a strong turbulence kinetic energy to further reconstruct the boundary layer. The second reason is that the formation of the recirculation zone between the flutes disturbs the boundary layer caused by the flow separation. With the increase of flute depth ratio (Ld/D), the separation vortex will become stronger and larger on the leeward side of flute. The separation vortex will break the boundary layer and improve the heat transfer capacity which is accompanied with the increase of fluid resistance. As the flute pitch length ratio (Lp/D) decreases, the spiral flow is strengthened, and meanwhile more wake flow is generated. The spiral flow causes little impact on enhancing heat transfer but inhibits the development of the separation vortex and fluid pulsation; in addition, the fluid resistance is reduced at the same time. The maximum value of the average Nusselt number appears when Re=5000, Ld/D=0.25 and Lp/D=1.00, which is 2.53 times the value of smooth tube. In view of the whole range of Reynolds number, the thermal performance enhancement factor indicates that Ld/D=0.15 and Lp/D=1.00 are the optimal geometric design parameters.

Physical space analysis of cross-scale turbulent kinetic energy transfer in premixed swirl flames

Understanding the cross-scale kinetic energy transport in turbulent flames is critical for physically-accurate modeling. This paper presents an experimental analysis of cross-scale kinetic energy transport in turbulent premixed swirl flames at Karlovitz numbers between 10 and 20 via physical space filtering. High-resolution tomographic particle image velocimetry and formaldehyde planar laser induced fluorescence measurements are used to obtain 3D velocity fields, as well as estimates for the progress variable and density fields. Filtering these fields at scales in the range of the laminar flame thickness (0.9<Δ/δL0<2.2) allows the kinetic energy transfer across the filter scale to be quantified. Mean kinetic energy transfer from sub-filter scales to larger scales (i.e. back-scatter) occurs internal to the flame structure across the range of conditions studied, with the maximum back-scatter occurring towards the center of the flame. Compared to equivalent non-reacting cases, considerably more back-scatter occurred in the reacting flows across all cases studied. At lower Karlovitz number, the magnitude of the back-scatter monotonically increased with increasing filter scale. At higher Karlovitz number, the back-scatter magnitude saturated at filter scales around Δ/δL0≈1.8. A scaling is proposed that quantifies the relative significance of the swirl-induced pressure gradient relative to the flame-induced pressure gradient on the pressure-work source of kinetic energy, indicating that swirling flow can significantly affect the kinetic energy dynamics. Overall, the results demonstrate that combustion significantly impacts the cross-scale kinetic energy transfer at scales in the range of the laminar flame thickness for conditions and configurations of practical relevance. These conclusions have implications for LES modelling strategies, providing evidence that models should allow for up-scale energy transfer in the vicinity of the flame.

Coronal Wave Trains and Plasma Heating Triggered by Turbulence in the Wake of a CME

Abstract Magnetohydrodynamic (MHD) turbulence plays an important role for the fast energy release and wave structures related to coronal mass ejections (CMEs). The CME plasma has been observed to be strongly heated during solar eruptions, but the heating mechanism is not understood. In this paper, we focus on the hot, dense region at the bottom of the CME and the generation of coronal wave trains therein using a high-resolution 2.5D MHD simulation. Our results show that the interaction between the tearing current sheet and the turbulence, including the termination shocks (TSs) at the bottom of the CME, can make a significant contribution to heating the CME, and the heating rate in this region is found to be greater than the kinetic energy transfer rate. Also, the turbulence can be somewhat amplified by the TSs. The compression ratio of the TS under the CME can exceed 4 due to thermal conduction, but such a strong TS is hardly detectable in all Solar Dynamics Observatory/Atmospheric Imaging Assembly bands. And turbulence is an indispensable source for the periodic generation of coronal wave trains around the CME.

Effects of Forcing Mechanisms on the Multiscale Properties of Magnetohydrodynamics

Abstract We performed numerical simulations to study the response of magnetohydrodynamics (MHD) to large-scale stochastic forcing mechanisms parameterized by one parameter, 0 ≤ a ≤ 1, going from direct injection on the velocity field (a = 1) to stirring acts on the magnetic field only (a = 0). We study the multiscale properties of the energy transfer by splitting the total flux in channels mediated by (i) the kinetic nonlinear advection, (ii) the Lorentz force, (iii) the magnetic advection, and (iv) the magnetic stretching term. We further decompose the fluxes into two subchannels given by heterochiral and homochiral components in order to distinguish forward, inverse, and flux-loop cascades. We show that there exists a quasi-singular role of the magnetic forcing mechanism for a ∼ 1: a small injection on the magnetic field a &lt; 1 can strongly deplete the mean flux of kinetic energy transfer throughout the kinetic nonlinear advection channel. We also show that this negligible mean flux is the result of a flux-loop balance between heterochiral (direct) and homochiral (inverse) transfers. Conversely, both homochiral and heterochiral channels transfer energy forward for the other three channels. Cross-exchange between velocity and the magnetic field is reversed around a = 0.4, and except when a ∼ 1, we always observe that heterochiral mixed velocity–magnetic energy triads tend to move energy from magnetic to velocity fields. Our study is an attempt to further characterize the multiscale nature of MHD dynamics by disentangling different properties of the total energy transfer mechanisms, which can be useful for improving subgrid modeling.

Interscale kinetic energy transfer in chemically reacting compressible isotropic turbulence

Abstract

Numerical investigations of Rayleigh–Taylor instability with a density gradient layer

The Rayleigh-Taylor instability (RTI) with a density gradient layer was investigated by implicit large eddy simulations (ILES) in a framework of three dimensional compressible multiphase flow with the single fluid approximation. The simulations are firstly initialized by multi-mode random perturbations in classic RTI and the associated case with a premixed layer. It is found that the late time behaviours of the turbulent mixing layer in classic and premixed cases are similar although an initial premixed layer slows down the growth of the turbulent mixing layer significantly. A variety of flow quantities for different cases are compared and studied at different time. In addition, the turbulent mixing caused by RTI with a single-mode dominated perturbation is investigated in classic and premixed cases. Different stages are identified for the time evolution of turbulent mixing layer. The dynamics of bubble-spike structures at early time, and the production and transfer of turbulent kinetic energy at late time are expatiated. Typical quantities of turbulent mixing are also summarized. It is found that there is an inactive stage before the fast growth of bubble-spike structures with an initial premixed layer and the spectra need more time to adjust until the flow turns to a self-similar regime.

Unraveling the Complex Structure of AGN-driven Outflows. V. Integral-field Spectroscopy of 40 Moderate-luminosity Type-2 AGNs

Abstract There is an ongoing debate on whether feedback from active galactic nuclei (AGNs) can effectively regulate the star formation activities in their host galaxies. To investigate the feedback effect of AGN-driven outflows, we perform integral-field spectroscopic observations of 40 moderate-luminosity ( erg s−1 ) Type-2 AGNs at z &lt; 0.1, which present strong outflow signatures in the integrated [O iii] kinematics. Based on the radial profile of the normalized [O iii] velocity dispersion by stellar velocity dispersion, we measure the kinematic outflow size and extend the kinematic outflow size–luminosity relation reported in Kang &amp; Woo into a wider luminosity range (over four orders of magnitude in [O iii] luminosity). The shallow slope of the kinematic outflow size–luminosity relation indicates that while ionizing photons can reach out further, kinetic energy transfer is much less efficient due to various effects, demonstrating the importance of kinematical analysis in quantifying the outflow size and energetics. By comparing the outflow kinematics with the host galaxy properties, we find that AGNs with strong outflows have higher star formation rate and higher H i gas fraction than those AGNs with weak outflows. These results suggest that the current feedback from AGN-driven outflows do not instantaneously suppress or quench the star formation in the host galaxies while its effect is delayed.

Advances in Thomson scattering diagnostics of plasmas used for chemical analysis

The use of plasmas for chemical analysis is prevalent and new sorts are continually being explored for potential applications in this field. However, the underlying mechanisms of characteristic processes that occur in plasmas are not completely understood. Free electrons drive chemical reactions, are essential to many plasma inherent processes, and are responsible for sustaining the discharge while governing the kinetic energy transfer between other species. Thomson scattering (TS) is a powerful plasma diagnostic technique for elucidating the fundamental electron parameters of number density, kinetic temperature, and energy distribution function. TS advantages include providing the direct, radially and temporally resolved probing of free electrons, with little-to-no perturbation of the plasma, with no prior assumptions of local thermodynamic equilibrium conditions, and simultaneous electron density/temperature measurements. The aim of this review is to provide a brief explanation of the TS theory and the experimental requirements, as well as highlight selected novel instrumentation advances and insights about chemical analysis plasmas discovered in the most recent TS publications, not previously covered in other reviews.

Kinetic Energy Flows in Activated Dynamics of Biomolecules

Protein conformational changes are activated processes essential for protein functions. Activation in a protein differs from activation in a small molecule in that it involves directed and systematic energy flows through preferred channels encoded in the protein structure. Understanding the nature of these energy flow channels and how energy flows through them during activation is critical for understanding protein conformational changes. We recently [W. Li and A. Ma, J. Chem. Phys. 144, 114103 (2016)] developed a rigorous statistical mechanical framework for understanding potential energy flows. Here, we complete this theoretical framework with a rigorous theory for kinetic energy flows: potential and kinetic energies interconvert when impressed forces oppose inertial forces, whereas kinetic energy transfers directly from one coordinate to another when inertial forces oppose each other. This theory is applied to analyzing a prototypic system for biomolecular conformational dynamics: the isomerization of an alanine dipeptide. Among the two essential energy flow channels for this process, dihedral ϕ confronts the activation barrier, whereas dihedral θ1 receives energy from potential energy flows. Intriguingly, θ1 helps ϕ to cross the activation barrier by transferring to ϕ via direct kinetic energy flow all the energy it received-an increase in θ1 caused by potential energy flow converts into an increase in ϕ. As a compensation, θ1 receives kinetic energy from bond angle α via a direct mechanism and bond angle β via an indirect mechanism.

Физико-математическая модель рабочего процесса вихревой трубы

Based on the physical model of the Ranque effect, proposed earlier, a simplified mathematical model of the working process of a vortex tube is compiled taking into account the exchange of work and heat during the interaction of peripheral and axial gas flows. The effect of viscosity and angular velocity gradient on the transfer of kinetic energy from the axis to the periphery is shown. The difference in thermodynamic temperatures when heat is supplied from the periphery to the axis is taken into account, which leads to a decrease in the cooling efficiency of the axial gas flow. Energy exchange is based on the assumption that the peripheral gas layers are compressed by the axial flow. The axial flow work is determined by the pressure difference between the valve and the outlet of the diaphragm

Phase‐field model for erosion processes

AbstractSolid particle erosion is one of the main damage mechanisms in high‐pressure compressors of jet engines. The significant shape change of the compressor blades leads to performance degradation over lifetime. To enhance predictive capabilities of erosive wear measurements under conditions, related to high pressure compressors, were performed. Even if there is no general model to describe erosive wear, it is understood that the transfer of kinetic energy from the impacting particle into the material is a central aspect in modelling erosion.In order to predict erosive wear of general geometries, Schrade et al. [9] developed a numerical model, based mainly on experimentally determined erosion rates. The shortcoming of such modelling approaches is the limited applicability in situations deferring to the measurement conditions. In the following, we will describe a physically based damage model, closing the gap between measurement and calculating shape changes of general specimens. Based on the phase‐field approach for predicting crack evolution presented by Miehe et al. [6], an overall energy balance of the considered specimen is constructed. A dissipative portion describes the influence of propagating damage, while special boundary conditions provides information about the energy transfer between impinging particles and specimen.

Единообразие рабочих процессов струйного и вихревого эжекторов, вихревой трубы и трубы Гартмана–Шпренгера

Based on the previously considered physical and mathematical models of jet and vortex ejectors, vortex tube and Hartmann–Sprenger tube, it makes a conclusion about the identity of the processes of exchange of work and heat in these devices. The influence of viscosity, tangential stresses, and the gradient of linear and angular velocities on the transfer of kinetic energy from a high-pressure to a low-pressure gas is shown. The difference of thermodynamic temperatures for heat exchange of high-pressure and low-pressure gases is taken into account.

Molecular dynamics study on the conversion mechanism between momentum and energy components in gas-surface interaction

With the rapid development of micro-nano technology and aerospace technology, researches related to rarefied gas flows have received more and more attention. For micro-/nanoscale systems and spacecraft in a rarefied environment, the reduction in the frequency of intermolecular collisions in the flow field makes the interaction between gas molecules and the solid surface develop into a major factor affecting the flow state. However, the mechanism of gas-surface interaction in rarefied flow has not been fully revealed due to its microscopic nature and physical complexity, and the existing simulation methods cannot accurately reflect the effect of this process on the flow state. In this paper, molecular beam method is adopted to simulate the scattering process of argon molecules on platinum surface, and the impacts of incident velocity, angle and wall roughness on the momentum and energy conversion mechanism are explored. By simulating the molecular scattering process under the two incident angles of &lt;inline-formula&gt;&lt;tex-math id="M3"&gt;\begin{document}$ 5^{\circ} $\end{document}&lt;/tex-math&gt;&lt;alternatives&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M3.jpg"/&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M3.png"/&gt;&lt;/alternatives&gt;&lt;/inline-formula&gt; and &lt;inline-formula&gt;&lt;tex-math id="M4"&gt;\begin{document}$ 75^{\circ}$\end{document}&lt;/tex-math&gt;&lt;alternatives&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M4.jpg"/&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M4.png"/&gt;&lt;/alternatives&gt;&lt;/inline-formula&gt;, the following conclusions are obtained. When colliding with the wall at an angle close to vertical, both components of the momentum of the gas molecules are lost. The normal energy transfers to the tangential direction, and when the molecular velocity is not less than 2.0, the transfer rate is not significantly affected by the incident energy of the molecule and the surface roughness. The total energy loss of gas molecules after scattering becomes significant with the increase of incident velocity, and it is not sensitive to changes of surface roughness. When the gas molecules are incident at &lt;inline-formula&gt;&lt;tex-math id="M5"&gt;\begin{document}$ 75^{\circ} $\end{document}&lt;/tex-math&gt;&lt;alternatives&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M5.jpg"/&gt;&lt;graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20201192_M5.png"/&gt;&lt;/alternatives&gt;&lt;/inline-formula&gt;, the roughness of the surface has a significant impact on the conversion mechanism of molecular momentum and energy. After colliding with a smooth wall, the momentum and energy values of the gas molecules remain basically unchanged, only the direction of the momentum is reversed. The motion state of molecules is close to the mirror reflection, and the conversion between momentum and energy components is not obvious. The introduction of roughness enhances the degree of accommodation between gas molecules and metal surface, and promotes the transfer of molecular tangential momentum and kinetic energy to the normal direction. When incident at a large polar angle, as opposed to the small-angle cases, the total energy loss of molecules is not sensitive to changes of incident velocity, it goes up significantly with the surface roughness increasing. The research in this article not only explores the gas-surface interaction mechanism, but also provides a useful reference for the high-fidelity simulation of rare gas flow and the development of appropriate gas-surface interaction models.

Research on the High-quality Development of Manufacturing Industry in Shandong Province Under the Background of Kinetic Energy Transfer

Under the background of the shift in driving forces, Shandong Province's manufacturing industry has entered a critical period of high-quality development, and it is urgent to construct a scientific index evaluation system to evaluate the state of development. In order to achieve this goal, this paper systematically combs the past research on the development of high-quality economy, combined with the connotation, concept and policy of high-quality development of manufacturing industry and considered the actual situation of the development of manufacturing industry in Shandong Province. A High-quality development index evaluation system of manufacturing industry in Shandong province with 20 indicators was established, including six dimensions of quality benefit, innovation-driven, environmental protection, coordinated development, opening up to the outside world and social feedback. Then, based on the collected data and starting from the above six dimensions, a comprehensive evaluation is made on the high-quality development of manufacturing industry in Shandong province in the five years from 2014 to 2018. Finally, based on the calculated comprehensive score, analyzing the high-quality development of manufacturing industry in Shandong province from 2014 to 2018, and putting forward reasonable Suggestions according to the existing deficiencies. The index evaluation system constructed in this paper is of great practical significance to the evaluation of the high-quality development of manufacturing industry in Shandong province in the future.

Relationship Between Humeral Energy Flow During the Baseball Pitch and Glenohumeral Stability.

Researchers suggest that motion deriving energy from the more proximal segments of the body is important to reduce injury susceptibility. However, limited clinical assessments have been associated with efficient energy flow within a complex movement such as the baseball pitch. This research aimed to determine the relationship between glenohumeral stability as determined by the closed kinetic chain upper extremity stability test and energy transfer into and out of the humerus during the baseball pitching motion. Kinematic and kinetic data were collected at 240 Hz on twenty-four baseball pitchers. Participants performed the closed kinetic chain upper extremity stability test prior to throwing three fastballs at game speed to a catcher with the fastest fastball used for analysis. Spearman's Rho were used to examine relationships between energy flow in and out of the humerus with glenohumeral stability as determined by the average score and normalized stance width during the closed kinetic chain upper extremity stability test. There was a significant negative correlation between the average score and normalized peak power leaving the humerus (r s[22]=-0.42, p=0.04). This result provides preliminary support for the use of the closed kinetic chain upper extremity stability test as a clinical assessment of a pitcher's ability to efficiently transfer energy within the upper extremity during the pitch.

In relation to question of development of controls, test of heatcover materials, for defence of workers of DSNS of Ukraine

Purpose. Development of means of control, testing of heat-protective materials used for the manufacture of personal protective equipment, both existing and at the stage of creating new ones. Method. Heat-protective materials for special clothing must be tested according to the nomenclature of quality indicators. We have considered the most important, which are associated with the effects of high-intensity heat radiation and high temperature. Results. The solution of the approximate value of the area of existence of the test method is offered. The test method is based on two methods. Previous: the test specimen is clamped in the frame and electric welding is performed near its surface. Particles of molten metal fall on the surface of the sample and leave traces in the form of burns, sticky particles. The depth of burn, the degree of adhesion, etc. are investigated. Currently, a more advanced method is used - the method of melting the welding electrode by blowing on the surface of the test material. However, both methods allow to obtain hot drops of different sizes, different weights, different directions relative to the test material and uncontrolled heating temperature of the hot drop, which does not allow to obtain high reliability of the results of the study. We proposed to create a device that allows you to control the size of the drop, the kinetic energy of the impact, the direction of flight and the temperature of the hot particle. All the above determined the direction of work on creating a methodology for studying these parameters and, as follows, the requirement to create an installation that would ensure the stability of parameters such as mass, velocity, temperature and flight trajectory of heated metal particles with the possibility of controlled change of these parameters. All the above determined the direction of work on creating a methodology for studying these parameters and, as follows, the requirement to create an installation that would ensure the stability of parameters such as mass, velocity, temperature and flight trajectory of heated metal particles with the possibility of controlled change of these parameters. To determine the area of existence of the research criteria by the proposed method, it is necessary to solve the problem with the following assumptions: the shape of a drop of metal is taken in the form of an ideal sphere; the droplet size is taken as the average; the drop is suspended on a non-thermally conductive thin thread in the air; air movement is excluded; heat transfer due to thermal conductivity is excluded from the calculation; the calculation does not take into account the process of oxidation of the surface of the hot drop and the formation of scale; the crystallization time of the metal is not taken into account. The process of influence of the hot metal ball on the investigated material is conditionally divided into three stages: heating of the ball to the set temperature and its control; the flight of the ball in the air with its subsequent cooling; the impact of the ball on the surface of the sample with the transfer of kinetic and thermal energy. In addition, it is necessary to control the force and set the direction of impact of the particle relative to the test material. The calculation of heat transfer processes is a complex mathematical problem that involves solving many systems of nonlinear equations. Using certain assumptions, we accept two mechanisms of heat transfer - molecular and convective. Scientific novelty. For the first time, a new method is proposed that allows to supplement the existing and get more reliable results. Practical meaningfulness. The installation of research of heat-protective materials on spark resistance is developed.

Significant Suppression of Star Formation in Radio-quiet AGN Host Galaxies with Kiloparsec-scale Radio Structures

Abstract We conducted 22 GHz 1″ Jansky Very Large Array imaging of 100 radio-quiet X-ray-selected active galactic nuclei (AGN) from the Swift–Burst Array Telescope (Swift–BAT) survey. We find AGN-driven kiloparsec-scale radio structures inconsistent with pure star formation in 11 AGN. The host galaxies of these AGN lie significantly below the star-forming main sequence, indicating suppressed star formation. While these radio structures tend to be physically small compared to the host galaxy, the global star formation rate of the host is affected. We evaluate the energetics of the radio structures interpreted first as immature radio jets, and then as consequences of an AGN-driven radiative outflow, and compare them to two criteria for successful feedback: the ability to remove the CO-derived molecular gas mass from the galaxy gravitational potential and the kinetic energy transfer to molecular clouds leading to v cloud &gt; σ *. In most cases, the jet interpretation is insufficient to provide the energy necessary to cause the star formation suppression. Conversely, the wind interpretation provides ample energy in all but one case. We conclude that it is more likely that the observed suppression of star formation in the global host galaxy is due to interstellar medium interactions of a radiative outflow, rather than a small-scale radio jet.

Competition between Ekman Plumes and Vortex Condensates in Rapidly Rotating Thermal Convection.

We perform direct numerical simulations of rotating Rayleigh-Bénard convection (RRBC) of fluids with low (Pr=0.1) and high (Pr≈5) Prandtl numbers in a horizontally periodic layer with no-slip bottom and top boundaries. No-slip boundaries are known to actively promote the formation of plumelike vertical disturbances, through so-called Ekman pumping, that control the ambient flow at sufficiently high rotation rates. At both Prandtl numbers, we demonstrate the presence of competing large-scale vortices (LSVs) in the bulk. Strong buoyant forcing and rotation foster the quasi-two-dimensional turbulent state of the flow that leads to the upscale transfer of kinetic energy that forms the domain-filling LSV condensate. The Ekman plumes from the boundary layers are sheared apart by the large-scale flow, yet we find that their energy feeds the upscale transfer. Our results of RRBC simulations substantiate the emergence of large-scale flows in nature regardless of the specific details of the boundary conditions.

Spectral shortcut in turbulence energy transfer in open channel flow over submerged vegetation

This study explores the characteristics of the spectral shortcut in the turbulence kinetic energy transfer in experimental open channel flows with the presence of submerged vegetation flow. The vegetation layer was simulated by arrays of rigid vertical cylinders, distributed uniformly in the channel bed. Results indicate that there are dual inertial subranges (ISRs) in the spectral distribution of turbulence energy in the penetration layer, where the Kelvin-Helmholtz (KH) and wake vortices coexist. The lower-frequency and higher-frequency ISRs reflect the energy cascading of the KH and wake-scale vortices, respectively. Spectral shortcut narrows the ISR for the KH vortex and contributes to the ISR for the wake-scale vortices, because such an action transfers a significant amount of turbulent energy directly from the large-scale eddies to the wake-scale vortices. We study the influence of spectral shortcut on energy transfer according to the turbulence kinetic energy budget equation for shear turbulence. The transferred energy is found to account for 58–71% of the shear turbulent energy and contributes considerably to the wake-scale turbulence. The strength of the energy transfer increases with the increase in the vegetation density and the mean bulk velocity and the decrease in the relative submergence.