Flux Dissipation Research Articles

Enhancing improved advection upstream splitting method on triangular grids: A hybrid approach for improved stability and accuracy in compressible flow simulations

This paper introduces NAUSM+M+AUFS (New Improved Advection Upstream Splitting Method Plus Artificially Upstream Flux Vector Splitting), a novel hybrid computational scheme for simulating compressible flows on triangular grids. The AUSM+M (Improved Advection Upstream Splitting Method) method is enhanced through two key modifications to boost numerical stability and robustness in high Mach number and hypersonic flows. The first modification redefines the interfacial numerical sound velocity, reducing shock anomalies and improving shock-capturing by integrating velocity and characteristic sound speed parameters. The second modification addresses the insufficiency of the pressure flux dissipation term at supersonic speeds by introducing a formulation that increases dissipation proportionally to the Mach number, thereby enhancing performance in high-speed flows. These enhancements constitute the NAUSM+M method. The NAUSM+M+AUFS scheme combines the strengths of NAUSM+M and AUFS (Artificially Upstream Flux Vector Splitting) methods, particularly in overcoming the limitations of NAUSM+M in handling shock instabilities and the carbuncle phenomenon on structure triangular grids. A dynamic switching function adjusts the weighting between NAUSM+M and AUFS, optimizing accuracy and stability based on local flow conditions. Numerical tests demonstrate that NAUSM+M+AUFS significantly outperforms AUSM+M, NAUSM+M, and AUFS, effectively eliminating the carbuncle phenomenon and providing smooth shock wave contours. In steady flow analysis, the new hybrid method achieves convergence speeds comparable to AUFS and shows 15% to 45% superior convergence accelerating than AUSM+M, depending on the convergence rate. In addition, in steady flow analysis, the accuracy of NAUSM+M+AUFS is 46% better than that of AUFS. This approach represents a significant advancement, offering a robust, accurate, and efficient solution for high-speed aerodynamic simulations, with broad applicability across various compressible flow challenges.

Non-Foliar Photosynthesis in Pea (Pisum sativum L.) Plants: Beyond the Leaves to Inside the Seeds

In addition to leaves, photosynthesis can occur in other green plant organs, including developing seeds of many crops. While the majority of studies examining photosynthesis are concentrated on the leaf level, the role of other green tissues in the production of total photoassimilates has been largely overlooked. The present work studies the photosynthetic behavior of leaves and non-foliar (pericarps, coats, and cotyledons) organs of pea (Pisum sativum L.) plants at the middle stage of seed maturation. The Chl a fluorescence transient was examined based on OJIP kinetics using the FluorPen FP 110. A discrepancy was observed between the performance index (PIABS) for foliar and non-foliar plant tissues, with the highest level noted in the leaves. The number of absorbed photons (ABS) and captured energy flow (TRo) per reaction center (RC) were elevated in the non-foliar tissues, which resulted in a faster reduction in QA. Conversely, the energy dissipation flux per RC (DIo/RC and PHI_Do) indicated an increase in the overall dissipation potential of active reaction centers of photosystem II. This phenomenon was attributed to the presence of a higher number of inactive RCs in tissues that had developed under low light intensity. Furthermore, the expression of genes associated with proteins and enzymes that regulate ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) activity was observed, including chaperonins Cpn60α and Cpn60β, RuBisCO activase, as well as phosphoribulokinase. The expression of these genes was found to differ between foliar and non-foliar tissues, indicating that the activation state of RuBisCO may be modified in response to light intensity. Overall, the present study provides insights into the mechanisms by which non-foliar green tissues of plants adapt to efficient light capture and utilization under low light conditions.

Enhanced flow boiling heat transfer with three-section sudden expansion microchannels

In this study, a three-section sudden expansion microchannels (TSE-MCs) heat sink was proposed to stabilize the flow boiling and improve the thermal performance of the heat sink exposed to high-heat-flux scenarios. The structural effect of newly designed TSE-MC and operating conditions on the heat transfer coefficient (HTC), pressure drop penalty, and flow instability were experimentally investigated and contrasted with continuous straight microchannels (CS-MCs). The experiments were performed at a saturation temperature of 35.5 °C, the mass flux ranging from 468–1033 kg/m2 s, and the heat flux up to ∼132 W/cm2. A comparative analysis based on the experimental results was conducted. Compared to CS-MCs, the nucleate boiling in TSE-MCs was initiated in advance with 0.2–1.2 °C reduction of wall superheat. The maximum HTCs at four mass fluxes, which was up to 62784 W/m2 K, were enhanced by 18.9–23.6 %. The uniformity of wall temperature was improved and the average wall temperature was reduced. HTCs and visualized results indicated that the dominant mechanism for heat transfer in TSE-MCs was nucleate boiling. Meanwhile, the pressure drop in TSE-MCs was slightly reduced, and pressure drop oscillations were greatly suppressed. The flow reversal in the inlet plenum was completely eradicated, and the performance evaluation criterion (PEC) of TSE-MC outperformed that of CS-MCs and was improved by 79.81 %–86.25 %. Overall, the present work demonstrates the great advantages of the newly proposed TSE-MCs, it offers a reference for the design of microchannel heat sinks for the real high heat flux dissipation applications.

Thermal management for microelectronic chips under non-uniform heat flux with supercritical CO2

With the rapid growth of information technology and the evolution in the use of microelectronic chips, these components are facing major challenges of high heat dissipation and inhomogeneous heat flux. To address the hotspot issues, a combination of microchannel heat sinks (MCHS) with cavity-rib designs and supercritical fluids is a potential solution. This study compares the thermo-hydraulic properties of water and supercritical carbon dioxide (sCO2) under various boundary conditions and hotspot locations during non-uniform heating. The results showed that sCO2 can effectively improve temperature uniformity along the heat sink in the presence of hotspots as compared to water. Considering a mass flow rate of 600 kg/(m2·s), the inhomogeneity index of the basal temperature of sCO2 is found to be 0.24, significantly lower than 4.22 for water. This indicates that sCO2 eliminates hot spots by rapidly increasing specific heat capacity near the pseudo-critical temperature. Furthermore, it is noted that maintaining the operating temperature of sCO2 near the pseudo-critical temperature can increase the specific heat capacity of the fluid in a short time, in addition to reducing the corresponding density and viscosity. Consequently, the entropy generation rate of sCO2 under ideal conditions is 46.6 % of that of water. Therefore, the proposed combination of a microchannel of complex structure and sCO2 in this study is demonstrated to effectively reduce the influence of hot spots and improve the overall thermal performance of heat sinks.

Radiative energy budgets of migrational microphytobenthic biofilms

Epipelic, biofilm-forming diatoms are key drivers of the primary production of mudflats. Such primary production is strongly affected by the vertical migration of diatoms, which is modulated by diurnal photoperiods, tidal cycles, and photoprotection mechanisms. However, the role of vertical migration in the radiative energy budget (REB) of microphytobenthic biofilms remains largely unknown. Here we used microsensor measurements of temperature and O2 in combination with reflectance spectroscopy and variable chlorophyll fluorimetry to construct the REB of intertidal, epipelic diatom-dominated biofilms for different emersion times (1, 3 and 5 h after the beginning of the in-situ emersion) and photon irradiance regimes, i.e., 400 and 800 µmol photon m−2 s−1. The effect of migration on REBs was studied by inhibiting diatom motility with Latrunculin A (Lat-A). Photosynthetic activity and light utilization efficiency decreased slightly, after adding Lat-A, while the amount of reflected light energy remained constant at ~ 23% of the incident irradiance and the majority (76–78%) of the incident light energy was dissipated as heat. Of the energy dissipated as heat, < 24% was dissipated upward in Lat-A treated samples, while an increasing downward heat dissipation was observed in Lat-A treated samples, as compared to control samples under an irradiance of 800 µmol photon m−2 s−1. However, we found no statistical significant differences in the REB and physiological parameters in the different treatments. Thus, we did not find any evidence that vertical migration of diatoms affected photosynthesis and light efficiency in the microphytobenthic biofilm over an emersion cycle, and a clear effect of non-photochemical quenching in REB and heat dissipation fluxes was not observed.

Impact of non-uniform heat flux, Arrhenius activation energy on gyrotactic microorganisms in conducting a nanofluid flow

ABSTRACT The primitive focus of this article is to examine the consequences of unsteady electrically conducting non-Newtonian magnetised tangent hyperbolic hybrid nanofluid flow which slides along the extensible surface with a porous medium along with Darcy–Forchheimer in a flow. Here we have taken into account the thermophoresis and Brownian movement for single- and multi-wall CNT dispersed in water. The temperature profile is accompanied by non-linear heat flux and viscous dissipation. The aftermath of activation energy on the concentration and the flow of gyrotactic microorganisms are taken into consideration. Differential equations after introducing various parameters are converted into ODE with the help of similarity transformations, which are later on, are solved using the bvp4c solver in the MATLAB software. For the range 0 ≤ Sq ≤ 4 there is an upsurge in the picture profiles of concentration and temperature obtained. However, the velocity of the flow gets diminished when the range of MHD and porosity parameter is confined between 0 ≤ M , K p ≤ 6 .

Adaptation of the Low Dissipation Low Dispersion Scheme for Reactive Multicomponent Flows on Unstructured Grids Using Density-Based Solvers

Abstract The low dissipation low dispersion (LD2) second-order accurate scheme is effective for scale-resolving simulations in finite volume computational fluid dynamics (CFD) solvers, thanks to its combination of a skew-symmetric split form for convective terms and matrix-valued artificial dissipation fluxes. However, reactive flow simulations face challenges due to steep gradients and varying gas properties. This study replaces the skew-symmetric scheme with the kinetic energy and entropy preserving (KEEP) scheme, utilizing quadratic and cubic split forms for convective terms, enhancing stability. The nonsmooth fluid interfaces in reactive flow simulations necessitate upwind fluxes for reactive scalars to limit total variation (TV), also requiring upwind fluxes for the mixture-dependent internal energy fluxes. Other convective terms use central discretizations from the KEEP scheme, leveraging LD2’s spatial reconstruction to minimize dispersive errors. Numerical assessments show this approach reduces spurious pressure oscillations in single and multicomponent flows. The absolute flux Jacobian for dissipation flux calculation is efficiently computed using an expanded Turkel’s approach for thermally perfect gas mixtures. Partial pressure derivatives are approximated when using the flamelet generated manifolds (FGM) combustion model. The proposed scheme is evaluated through scale-resolving simulations of the Cambridge burner flame SWB1 on an unstructured grid using the density-based solver TRACE, employing both finite rate chemistry (FRC) and FGM combustion models. Comparative analysis with the all-speed SLAU2 scheme shows the superior performance of the proposed scheme in handling turbulent reactive multicomponent flows.

Efficient entropy-stable discontinuous spectral-element methods using tensor-product summation-by-parts operators on triangles and tetrahedra

We present a new class of efficient and robust discontinuous spectral-element methods of arbitrary order for nonlinear hyperbolic systems of conservation laws on curved triangular and tetrahedral unstructured grids. Such discretizations employ a recently introduced family of sparse tensor-product summation-by-parts (SBP) operators in collapsed coordinates within an entropy-conservative modal formulation, which is rendered entropy stable when a dissipative numerical flux is used at element interfaces. The proposed algorithms exploit the structure of such SBP operators alongside that of the Proriol–Koornwinder–Dubiner polynomial basis used to represent the numerical solution on the reference triangle or tetrahedron, and a weight-adjusted approximation is employed in order to efficiently invert the local mass matrix for curvilinear elements. Using such techniques, we obtain an improvement in time complexity from O(p2d) to O(pd+1) relative to existing entropy-stable formulations using multidimensional SBP operators not possessing such a tensor-product structure, where p is the polynomial degree of the approximation and d is the number of spatial dimensions. The number of required entropy-conservative two-point flux evaluations between pairs of quadrature nodes is accordingly reduced by a factor ranging from 1.56 at p=2 to 4.57 at p=10 for triangles, and from 1.88 at p=2 to 10.99 at p=10 for tetrahedra. Through numerical experiments involving smooth solutions to the compressible Euler equations on isoparametric triangular and tetrahedral grids, the proposed methods using tensor-product SBP operators are shown to exhibit similar levels of accuracy for a given mesh and polynomial degree to those using multidimensional operators based on symmetric quadrature rules, with both approaches achieving order p+1 convergence with respect to the element size in the presence of interface dissipation as well as exponential convergence with respect to the polynomial degree. Furthermore, both operator families are shown to give rise to entropy-stable schemes which exhibit excellent robustness for test problems characteristic of under-resolved turbulence simulations. Such results suggest that the algorithmic advantages resulting from the use of tensor-product operators are obtained without compromising accuracy or robustness, enabling the efficient extension of the benefits of entropy stability to higher polynomial degrees than previously considered for triangular and tetrahedral elements.

Design and performance assessment of a triply-periodic-minimal-surface structures-enhanced gallium heat sink for high heat flux dissipation: A numerical study

This study numerically investigates a phase-change material heat sink using gallium and Primitive Triply Periodic Minimal Surface (TPMS) cells structure as in-fill for applications requiring high heat-flux dissipation, e.g., electronics. Initially, we used only gallium without thermal conductivity enhancers, relying solely on buoyancy-driven circulations of melted gallium for the convective cooling of a hot sink base. However, this study aims to surpass gallium’s innate heat-dissipation capability. Therefore, the sink is enhanced with a high conductivity Primitive TPMS cells structure. Hybridization of conduction and convection heat dissipation enhancements is accomplished by using only one layer of the TPMS cells installed at the hot sink base. Comparison with the full TPMS structure filling option is made. In the full TPMS structure filling option, the sink relies mainly on conduction through the TPMS structure’s body and less on natural convection. However, equipping the sink with TPMS structures reduces the overall latent heat storage capacity. Therefore, additional gallium is added to the sink to match the overall gallium content in the baseline case without TPMS structures. Furthermore, the effect of the boundary conditions applied at the wall is explored. The results show considerable improvements in heat dissipation and peak temperatures with the TPMS cells, where by the time 100 s (about 20 s post complete melting) peak temperatures are about 13 percent lower than in the case without TPMS structures. Furthermore, the full structure filling option demonstrates superior performance over the partially filled ones, highlighting the importance of conduction through TPMS cells over convection in the free gallium space. Unlike the partial filling option, conduction in the full filling option has a continuous favorable impact on heat dissipation from the onset of the heating process.

Thermal Conductivity of AlSi12/Al2O3-Graded Composites Consolidated by Hot Pressing and Spark Plasma Sintering: Experimental Evaluation and Numerical Modeling

Functionally graded metal matrix composites have attracted the attention of various industries as materials with tailorable properties due to spatially varying composition of constituents. This research work was inspired by an application, such as automotive brake disks, which requires advanced materials with improved wear resistance on the outer surface as combined with effective heat flux dissipation of the graded system. To this end, graded AlSi12/Al2O3 composites (FGMs) with a stepwise gradient in the volume fraction of alumina reinforcement were produced by hot pressing and spark plasma sintering techniques. The thermal conductivities of the individual composite layers and the FGMs were evaluated experimentally and simulated numerically using 3D finite element (FE) models based on micro-computed X-ray tomography (micro-XCT) images of actual AlSi12/Al2O3 microstructures. The numerical models incorporated the effects of porosity of the fabricated AlSi12/Al2O3 composites, thermal resistance, and imperfect interfaces between the AlSi12 matrix and the alumina particles. The obtained experimental data and the results of the numerical models are in good agreement, the relative error being in the range of 4 to 6 pct for different compositions and FGM structure. The predictive capability of the proposed micro-XCT-based FE model suggests that this model can be applied to similar types of composites and different composition gradients.

Thermal and Dynamo Evolution of the Lunar Core Based on the Transport Properties of Fe‐S‐P Alloys

AbstractPaleomagnetic analyses have suggested that the lunar magnetic field underwent a significant change from 4.25 to 3.19 Ga, indicating the rapid transition of the lunar dynamo mechanism. We used the van der Pauw (vdP) method to measure the electrical resistivity of Fe‐S‐P alloys under conditions relevant to the lunar core and estimated the thermal conductivity of the Fe‐S‐P lunar core. These values were incorporated into thermal and dynamo models to investigate the evolution of the lunar core. Our model indicates that the inner core began to grow as early as 4.35 Ga, the solidification regime switched at 3.50 Ga, and the thermal dynamo ceased between 3.78 and 3.51 Ga. The cessation of the dynamo could be due to a low buoyancy flux and insufficient entropy dissipation. Thermal and compositional dynamos cannot sustain the ancient strength of the Moon's magnetic field, and require other energy sources.

Insights on Lateral Gravity Wave Propagation in the Extratropical Stratosphere From 44 Years of ERA5 Data

AbstractThe study presents (a) a 44‐year wintertime climatology of resolved gravity wave (GW) fluxes and forcing in the extratropical stratosphere using ERA5, and (b) their composite evolution around gradual (final warming) and abrupt (sudden warming) transitions in the wintertime circulation, focusing on lateral fluxes. The transformed Eulerian mean equations are leveraged to provide a glimpse of the importance of GW lateral propagation (i.e., horizontal propagation) toward driving the wintertime stratospheric circulation by analyzing the relative contribution of the vertical versus meridional flux dissipation. The relative contribution from lateral propagation is found to be notable, especially in the Austral winter stratosphere where lateral (vertical) momentum flux convergence provides a peak climatological forcing of up to −0.5 (−3.5) m/s/day around 60°S at 40–45 km altitude. Prominent lateral propagation in the wintertime midlatitudes also contributes to the formation of belts of GW activity in both hemispheres.

Chemically reactive non-Newtonian fluid flow through a vertical microchannel with activation energy impacts: A numerical investigation

This work examines the second law analysis of an electrically conducting reactive third-grade fluid flow embedded with the porous medium in a microchannel with the influence of variable thermal conductivity, activation energy, viscous dissipation, joule heating, and radiative heat flux. A suitable non-dimensional variable is included into the governing equations to transform them into an ensemble of equations that are devoid of dimensions. The acquired equations are then tackled using the Runge Kutta Felhberg 4th and 5th order (RKF-45) approach in conjunction with the shooting methodology. Through comparison with the current results, the numerical results are verified, which provides a good agreement. From the present outcomes, it is established that the entropy generation is supreme for the viscous heating constraint, variable thermal conductivity, Frank Kameneski, heat source ratio parameter and third-grade fluid material constraint. The Bejan number boosts up with larger values of activation energy, and Frank Kameneski constraint and the decreasing nature is noticed for increasing third-grade material parameter, viscous heating parameter. With magnetism, the fluid’s velocity slows down because of a resistive force. A similar impact in the channel on velocity is noticed for larger third-grade fluid, activation energy parameter, and Frank-Kameniski parameters and increasing behavior is noticed for variable thermal conductivity, and permeability parameter. Further, it is cleared that the variable thermal conductivity assumption in the channel plate leads to a significant under prediction of the irreversibility rate.

Comprehensive comparative study of experimental and simulated critical heat flux in special high-flux cooling devices: The Short Helical Minichannel-Evaporators

Short Helical Minichannel Evaporators are compact heat exchangers characterized by small, helical channels that allow high heat flux dissipation by means of direct cooling. It is a promising cooling solution in applications requiring high heat transfer rates in a limited space, such as power electronics, machining processes, injection molding among others. Optimal and safe operation of these devices is critically dependent on accurate determination of the critical heat flux (CHF) when nucleate boiling changes to filmwise regime. Misestimation of the CHF could lead to system burnout or suboptimal performance, highlighting the need for reliable theoretical models. In this study, the performance of a theoretical model was compared with a series of experiments carried out on a custom-built test rig. The results show a strong correlation between the experimental data and the adapted Groeneveld model, with a Mean Absolute Error (MAE) of 8.51kWm−2, a Mean Error (ME) of −4.71kWm−2, and a Deviation (Dev) of 8.77kWm−2. Notably, 96.8% of the simulated values were within a 15% error band. The validated model is also applied to increase knowledge about design parameters beyond the experimental data. The study emphasizes the practicality of the Groeneveld model in accurately calculating the CHF for these specific heat exchangers, encouraging improvements for performance and operational safety.

Network Derivation of Liquid Junction Potentials in Single-Membrane System.

Peusner's network thermodynamics (PNT) is one of the more important formalisms of nonequilibrium thermodynamics used to describe membrane transport and the conversion of the internal energy of the system into energy dissipated in the environment and free energy used for the work involved in the transport of solution components in membrane processes. A procedure of transformation the Kedem-Katchalsky (K-K) equations for the transport of binary electrolytic solutions through a membrane to the Kedem-Katchalsky-Peusner (K-K-P) equations based on the PNT formalism for liquid junction potentials was developed. The subject of the study was a membrane used for hemodialysis (Ultra Flo 145 Dialyser) and aqueous NaCl solutions. The research method was the L version of the K-K-P formalism for binary electrolyte solutions. The Peusner coefficients obtained from the transformations of the K-K formalism coefficients for the transport of electrolyte solutions through the artificial polymer membrane were used to calculate the coupling coefficients of the membrane processes and to calculate the dissipative energy flux. In addition, the dissipative energy flux, as a function of thermodynamic forces, made it possible to investigate the energy conversion of transport processes in the membrane system.

Anisotropic stellar evolution and exotic matter

In this paper, we discuss the stability of isotropic pressure conditions for a spherically symmetric dissipative fluid distribution in the framework of f(G,T) gravity. We consider the fluid to be composed of seen and exotic matter particles. The Gauss Bonnet terms represent exotic matter particles. For the physical significance of the pressure isotropy conditions, we transform the system into the hydrostatic equilibrium approximation. We observe the presence of shear, dissipative fluxes, energy density inhomogeneities, and prominently, the exotic matter tends to abandon isotropy leading to pressure anisotropy. It is found that exotic matter and dissipation are major factors that induce matter anisotropy in the evolving stellar system. In order to discuss the physical significance of the stellar model in f(G,T) gravity, the behaviour of stellar structure is explored according to the observational data of a compact star 4U1820 − 30. It is found that f(G,T) terms indicating the exotic material in the stellar model plays a vital role in governing the dynamics of the evolution. To strengthen the results, we also incorporate some arguments by choosing an axially symmetric case.

Finite difference analyses of bioconvective Williamson nanofluids stream over irregular plates with effects of nonlinear radiation and viscous dissipation

The purpose of this work is to provide a comprehensive analysis of the bioconvective Williamson nanofluid stream while considering the effects of radiation flux and viscous dissipation. The two-phase nanofluids model is applied where the impacts of the Brownian motion and thermophores are significant. This study starts with introducing the governing system in case of the irregular plane then it transforms to the regular plane. The solution methodology is based on the fully implicit finite difference method. The major results disclosed that maximizing the amplitude parameter causes a diminishing in the velocity and skin-friction coefficients. Also, lower behaviors are noted for the velocity in the case of Williamson nanofluids compared to a Newtonian nanofluid case (We = 0). Furthermore, the considered range of Biot number (1 ≤ Bi ≤ 5)causes an improvement in the surface temperature up to 71.59%.

Non-similar analysis of radially magnetized flow and heat transfer of Reiner–Philippoff based nanofluid over a curved stretching surface with viscous dissipation

The aim of this study is to conduct a non-similar analysis of flow and heat transfer rheology of non-Newtonian fluid over a radially magnetized curved stretching surface in the presence of multiple type of nanoparticles. Reiner–Philippoff viscosity and homogenous models are incorporated in the governing equation to study the effects of non-Newtonian fluid and nanoparticles respectively. Reiner–Philippoff viscosity model is a complicated non-Newtonian fluid model presenting an implicit stress-strain relationship. This fluid model has ability to present viscosity behavior in response to varying viscoelastic conditions of shear-thinning, shear-thickening as well as Newtonian fluid. The nanoparticles of nickel, molybdenum disulfide, and tantalum are used to study the enhancement of the thermal conductivity of the fluid with influences of radiative heat flux and viscous dissipation. To attain a more precise and generalized analysis of the heat transfer and flow, the governing boundary layer equations are converted to non-similar form. The local non-similarity method up to second level of truncation is employed to numerically solve the resulting non-similar PDEs via bvp4c in MATLAB tools. To examine the impact of physical factors on flow and heat transfer, numerical data are visually and tabulated displayed. It is worth mentioning that the thermal radiation, curvature parameter, and magnetic number play important role in controlling wall drag and heat flux.

Non-Fourier heat flux and Joule dissipation in hybrid nanoparticles suspension with Williamson fluid

Non-Fourier heat flux and Joule dissipation in hybrid nanoparticles suspension with Williamson fluid

Characterizing Subglacial Hydrology Within the Amery Ice Shelf Catchment Using Numerical Modeling and Satellite Altimetry

AbstractMeltwater forms at the base of the Antarctic Ice Sheet due to geothermal heat flux (GHF) and basal frictional dissipation. Despite the relatively small volume, this water has a profound effect on ice‐sheet dynamics. However, subglacial melting and hydrology in Antarctica remain highly uncertain, limiting our ability to assess their impact on ice‐sheet dynamics. Here we examine subglacial hydrology within the Amery Ice Shelf catchment, East Antarctica, using the subglacial hydrology model GlaDS. We calculate subglacial melt rates using a higher‐order ice‐flow model and two GHF estimates. We find a catchment‐wide melt rate of 7.03 Gt year−1 (standard deviation = 1.94 Gt year−1), which is ≥50% greater than previous estimates. The contribution from basal dissipation is approximately 40% of that from GHF. However, beneath fast‐flowing ice streams, basal dissipation is an order of magnitude larger than GHF, leading to a significant increase in channelized subglacial flux upstream of the grounding line. We validate GlaDS using high‐resolution interferometric‐swath radar altimetry, with which we detect active subglacial lakes and fine‐scale ice‐shelf basal melting. We find a network of subglacial channels that connects areas of deep subglacial water coincident with active subglacial lakes, and channelized discharge at the grounding line coinciding with enhanced ice‐shelf basal melting. The concentrated discharge of meltwater provides 36% of the freshwater released into the ice‐shelf cavity, in addition to ice‐shelf basal melting. This suggests that ice‐shelf basal melting is strongly influenced by subglacial hydrology and could be affected by future changes in subglacial discharge, such as lake drainage or channel rerouting.