Battery cold plates link temperature control to the manufacture, assembly and recovery of electric vehicle battery packs. Channel improvements become useful components when thermal performance, production integrity and end-of-life access are qualified together. This Mini Review develops that component perspective through a focused narrative synthesis of recent literature, mainly from 2026. It connects channel design, joining, thermal interfaces and life-cycle assessment through three qualification gates. Representative published results show the scale and context of the design choices. In one modeled square-plate case, bidirectional flow reduced the temperature spread at the thermal interface surface from 2.0 °C to 0.62 °C. In a separate life-cycle study of a switchable heat-pipe system, its aluminum cooling plate contributed 86% of production-phase climate impact. These results identify both thermal and material priorities within their respective systems. The proposed gates require thermal–hydraulic results, production evidence and recovery evidence to describe the same plate configuration. A common qualification record can then support design transfer and supplier comparison. Priorities are matched thermal benchmarks, durability tests of the assembled plate and interface, and measured disassembly and recovery outcomes.
Vertical-axis wind turbines (VAWTs) are increasingly considered for distributed, urban, and offshore wind-energy applications, but unsteady aerodynamic loading, dynamic stall, wake interactions, and aeroacoustic emissions limit their wider deployment. This critical review examines VAWT development from a coupled aerodynamic-aeroacoustic perspective, with particular emphasis on dynamic stall, flow-control strategies, computational and experimental assessment, multi-objective optimization, and data-driven design. The reviewed evidence shows that dynamic stall should not always be treated solely as a loss mechanism; controlling its timing and severity can improve torque production while reducing transient loading. Passive and active flow-control methods can provide simultaneous aerodynamic and acoustic benefits, although substantial trade-offs also occur. In particular, configurations that strongly increase aerodynamic loading may increase impulsive or blade-passing noise, while reductions in overall sound pressure level can conceal frequency-dependent or directional acoustic penalties. High-fidelity detached-eddy simulation (DES), delayed detached-eddy simulation (DDES), and large-eddy simulation (LES) coupled with acoustic analogies provide valuable information on noise-generation mechanisms. In contrast, unsteady Reynolds-averaged Navier-Stokes (URANS) and lower-fidelity approaches remain useful for screening and optimization. Recent surrogate and machine-learning methods substantially reduce the computational cost of multi-objective searches and have enabled direct power-noise optimization. However, model generalization, uncertainty propagation, synchronized aerodynamic-acoustic experimental validation, and optimization over realistic operating envelopes remain insufficiently developed. The review identifies simultaneous optimization of power output, acoustic emission, and cyclic aerodynamic loading as a fatigue-relevant design metric for VAWTs and proposes a multi-fidelity, physics-supported, data-assisted framework for robust aerodynamic-aeroacoustic co-design.
In the aviation industry, hydrogen is the only option available today to achieve zero carbon emissions. However, safe utilization of hydrogen at the system level remains largely unaddressed in current research, which tends to focus on individual components rather than integrated systems. We present a feasibility analysis of hydrogen combustion in a gas turbine embedded within the Hydrogen Aviation Lab (HAL) infrastructure under realistic physical and economic boundary conditions. The novelty of this work lies in the retrofit approach to enable hydrogen combustion in an existing gas turbine with minimal changes; this avoids a full redesign of the combustion system while achieving system-level operability. The feasibility of hydrogen combustion was analyzed by modeling the thermodynamic process. The fuel-to-air ratio (FAR) was introduced as a unified control parameter that governs combustion stability, turbine entry temperature (TET), and operational safety simultaneously. At a design point representative of an auxiliary power unit (APU), a FAR of 0.016173 was identified to enable safe and stable hydrogen combustion, resulting in a hydrogen mass flow of 0.016006 kg/s; this suggests an equivalence ratio of 0.24737, which is within the margin for consistent and safe hydrogen combustion. Furthermore, the airstreams inside the combustion chamber were modified to enable more mixing of dilution air with the hot combusted air and cooling of the overall gas path air. To condition the combustion gases to the target TET of 1,293.15 K, a dilution air fraction of ε = 55.012% corresponding to an air mass flow of 2.2 kg/s was identified. The TET was fixed through APU design and material constraints. NOx emissions were deliberately excluded from this study as they were outside the defined system boundary. The results demonstrate that a feasible hydrogen combustion system can be realized through pragmatic retrofitting, which provides a foundation for further developments within integrated hydrogen aviation infrastructures.
Electro-chemo-mechanical coupling is well established in electric-vehicle batteries, yet its translation from electrode behavior to pack- and vehicle-level performance remains difficult. This mini-review organizes the evidence around five transferable descriptors: electrode/cell swelling, contact or stack pressure, stiffness and strength, mechanical-abuse tolerance, and inactive structural mass or volume. Recent studies are examined to show how silicon-rich electrode deformation, pressure-dependent solid-state interfaces, and structural integration influence practical energy density and safety. Building on established mechanisms, we propose a mechanical penalty ledger that defines consistent accounting boundaries and connects cell-level specific energy with the mass and volume of constraint, protection, interconnection, and thermal-management components. An illustrative 60 kWh case study compares conventional, structurally optimized, and higher-specific-energy battery architectures. Under the stated hypothetical assumptions, a 12% improvement in cell-level specific energy yields only an approximately 3.3% improvement in pack-level specific energy when additional compression hardware is included. A break-even calculation identifies an illustrative maximum allowable compression-hardware mass of approximately 33.7 kg for the higher-energy configuration to outperform the conventional reference. The worked example is a sensitivity demonstration rather than experimental validation or a universal design threshold. This review therefore provides a transparent basis for evaluating when electrochemical improvements survive mechanical integration penalties, while emphasizing the need for experimentally validated load paths, ageing-conditioned safety limits, and complete component-level inventories.
Manufacturing operators must maintain production while limiting emissions when disturbances spread through shared resources. This simulation-only study examines that trade-off in a reduced-order, five-layer manufacturing network; no physical-plant calibration or live digital-twin connection is available. The prototype combines sparse hypergraph risk features, temporal damage memory and a soft actor-critic controller with carbon and tail-excess penalties. Trained policies are evaluated on four held-out synthetic networks using 50 paired disturbance seeds and three initialization seeds. The proposed controller achieves mean resilience 0.875, compared with 0.442 without intervention and 0.947 for HG-SAC. Its emissions are 24.0% lower than HG-SAC, but it exceeds the allowance in 87.5% of trajectories. Paired effect sizes, multiplicity corrections, retrained ablations and shifted-disturbance tests clarify the trade-offs and limitations. The results show a trade-off between emissions and resilience under the simulated conditions. Prospective plant calibration and shadow validation remain necessary.
