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Liquid hydrogen storage, thermal management, and transfer-control system for integrated zero emission aviation (IZEA)

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Applied Energy 2025年 393卷

作者： Virdi, Parmit S. Guo, Wei Cattafesta, Louis N. Cheetham, Peter Cooley, Lance Gladin, Jonathan C. He, Jiangbiao Kim, Chul Li, Hui Ordonez, Juan Pamidi, Sastry Zheng, Jian-Ping Mechanical Engineering Department FAMU-FSU College of Engineering 2525 Pottsdamer St TallahasseeFL32310 United States National High Magnetic Field Laboratory 1800 E Paul Dirac TallahasseeFL32310 United States Illinois Institute of Technology 10 West 32th Street ChicagoIL60616 United States Electrical and Computer Engineering Department FAMU-FSU College of Engineering 2525 Pottsdamer St TallahasseeFL32310 United States Center for Advance Power Systems 2000 Levy Avenue TallahasseeFL32310 United States Applied Superconductivity Center 2031 E Paul Dirac Dr TallahasseeFL32310 United States Daniel Guggenheim School of Aerospace Engineering Georgia Tech North Avenue AtlantaGA30332 United States Aerospace Systems Design Laboratory 275 Ferst Drive NW AtlantaGA30332 United States Department of Electrical Engineering and Computer Science University of Tennessee 1520 Middle Dr KnoxvilleTN37996 United States Department of Electrical Engineering University at Buffalo 230 Davis Hall University at Buffalo North Campus BuffaloNY14260 United States

The rapid growth of the aviation sector underscores the urgent need to reduce carbon and contrail emissions, key contributors to climate change. Hydrogen, with its high specific chemical energy, emerges as a promising clean fuel alternative. To promote sustainable aviation, we propose an innovative design for a liquid hydrogen storage, thermal management, and transfer-control system tailored for Integrated Zero Emission Aviation (IZEA). Our design harnesses the cooling power of liquid hydrogen to manage the temperature and thermal loads on essential power system components. By regulating the pressure in the storage tank, we demonstrate the feasibility of delivering the required hydrogen mass flow rates—up to 0.25 kg/s—to meet a peak power demand of 16.2 MW for a prototype 100-passenger hybrid-electric aircraft, while efficiently cooling the power system using practical heat exchangers. Through comprehensive system-level optimization, we have identified the optimal tank and heat exchanger configurations that maximize the overall gravimetric index to a value of 0.62, where the index is defined as the ratio of the hydrogen fuel mass to the total mass of the fuel, storage tank, and thermal management system. Our findings emphasize the critical importance of system-level optimization in determining key design parameters, paving the way for zero-emission aviation technologies and advancing environmental sustainability in the aviation industry. © 2025 The Author(s)

关键词： Air conditioning

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A MOLECULAR-MODEL OF PROTEOGLYCAN-ASSOCIATED ELECTROSTATIC FORCES IN CARTILAGE MECHANICS

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JOURNAL OF BIOMECHANICAL engineering-TRANSACTIONS OF THE ASME 1995年第2期117卷 179-192页

作者： BUSCHMANN, MD GRODZINSKY, AJ Continuum Electromechanics Group Laboratory for Electromagnetic and Electronic Systems Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139

Measured values of the swelling pressure of charged proteoglycans (PG) in solution (Williams RPW, and Comper WD;Biophysical Chemistry 36:223, 1990) and the ionic strength dependence of the equilibrium modulus of PG-rich articular cartilage (Eisenberg SR, and Grodzinsky AJ;J Orthop Res 3: 148, 1985) are compared to the predictions of two models. Each model is a representation of electrostatic forces arising from charge present on spatially fixed macromolecules and spatially mobile micro-ions. The first is a macroscopic continuum model based an Donnan equilibrium that includes no molecular-level structure and assumes that the electrical potential is spatially invariant within the polyelectrolyte medium (i.e. zero electric field). The second model is based on a microstructural, molecular-level solution of the Poisson-Boltzmann (PB) equation within a unit cell containing a charged glycosaminoglycan (GAG) molecule and its surrounding atmosphere of mobile ions. This latter approach accounts for the space-varying electrical potential and electrical field between the GAG constituents of the PG. In computations involving no adjustable parameters, the PB-cell model agrees with the measured pressure of PG solutions to within experimental error (10%), whereas the ideal Donnan model overestimates the pressure by up to 3-fold. In computations involving one adjustable parameter for each model, the PB-cell model predicts the ionic strength dependence of the equilibrium modulus of articular cartilage. Near physiological ionic strength the Donnan model overpredicts the modulus data by 2-fold, but the two models coincide for low ionic strengths (C-0 < 0.025M) where the spatially invariant Donnan potential is a closer approximation to the PB potential distribution. The PB-cell model result indicates that electrostatic forces between adjacent GAGs predominate in determining the swelling pressure of PG in the concentration range found in articular cartilage (20-80 mg/ml). The PB-cell mod

关键词： swelling pressure Donnan equilibrium Pressure Ionic Strength adjustable parameter Electrostatics Electrostatic force picogram Cartilage potential unit cell

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AN ANALYSIS OF ELECTROQUASISTATIC INDUCTION MICROMOTORS

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SENSORS AND ACTUATORS 1989年第1-2期20卷 97-106页

作者： BART, SF LANG, JH Laboratory for Electromagnetic and Electronic Systems Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

This paper studies the steady-state operation of the electroquasistatic induction micromotor (IM). A rotary pancake IM compatible with surface micromachining serves as an example. A model is developed to predict the electric potential, field and free charge within the IM. The model also predicts the motive torque and transverse force of electric origin acting on its rotor. The torque is balanced against bushing friction and windage to determine rotor velocity. Here, the bushing friction is modeled as a function of the transverse force acting on the rotor. Finally, an equivalent circuit model is developed, which described important aspects of the electromechanical operation of the IM. The model is used to study IM performance and its dependence on IM dimensions and material properties. For example, IM performance is predicted to be a complex function of axial IM dimensions and a strong function of rotor conductivity. The study also reveals that IM performance can differ significally from that of the variable-capacitance micromotor (VCM). For example, the dependence of motive torque and transverse force on axial dimensions can be significanly different in some IM operating regimes, allowing the possibility of improved performance over the VCM. IM and VCM dependences on micromotor geometry, velocity and material properties can also be significanlty different. The excitation and control requirements reflect the difference between a synchronous (VCM) and an asynchronous (IM) motor, as well as the possibility of obtaining an axially stable rotor position for certain IM material parameters.

关键词： Electric Motors, Induction

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NONINVASIVE ION-DRAG VELOCIMETER

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JOURNAL OF ELECTROSTATICS 1989年第1期24卷 67-77页

作者： MELCHER, JR Department of Electrical Engineering and Computer Science and Laboratory for Electromagnetic and Electronic Systems Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

A device is described which, while mounted flush with a wall bounding a streaming insulating fluid, can be used to deduce the velocity profile with respect to the coordinate normal to the wall. Ions, injected into the stream through a fine-meshed screen having a controlled potential V , migrate upstream along trajectories that sample the velocity profile. By means of finely divided electrodes that are also in the wall, the location, V , demarcating those ions that make it back to the upstream wall from those swept downstream is measured as a function of V . An algorithm is developed for deducing the velocity profile from the data ( V , Y ). It is shown to be readily implemented with a microcomputer, which could oversee making the measurements.

关键词： Velocimeters

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DESIGN CONSIDERATIONS FOR MICROMACHINED ELECTRIC ACTUATORS

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SENSORS AND ACTUATORS 1988年第3期14卷 269-292页

作者： BART, SF LOBER, TA HOWE, RT LANG, JH SCHLECHT, MF Laboratory for Electromagnetic and Electronic Systems Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

This paper provides a perspective on the design and fabrication of surface-micromachined actuators. An analysis of electromagnetic to mechanical energy conversion indicates that electric drive is preferable to magnetic drive for these microactuators. Planar rotary and linear microactuators can be fabricated by selectively etching multi-layer thin-film sandwiches, with the potential for gaps on the order 1 μm and lateral dimensions on the order of 300 μm. Prototype designs are presented for rotary variable-capacitance and induction micromotors. Rotor speeds of 2.4 × 10 5 rad s −1 (2.3 × 10 6 rpm) and accelerations of 2.9 × 10 9 rad s −2 appear feasible for both. In conclusion, some of the research problems in developing a microactuator technology are identified, including warpage of microstructural films due to residual stress, friction between micromachined surfaces and electric breakdown in small gaps.

关键词： ACTUATORS

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A MULTI-RESOLUTION, PROBABILISTIC APPROACH TO TWO-DIMENSIONAL INVERSE CONDUCTIVITY PROBLEMS

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SIGNAL PROCESSING 1989年第3期18卷 291-311页

作者： CHOU, KC WILLSKY, AS Laboratory for Information and Decision Systems Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

In this paper a method of estimating the conductivity in a bounded 2-D domain at multiple spatial resolutions given boundary excitations and measurements is presented. The problem is formulated as a maximum-likelihood estimation problem and an algorithm that consists of a sequence of estimates at successively finer scales is presented. By exploiting the structure of the physics, the problem at each scale is divided into two linear subproblems, each of which is solved using parallelizable relaxation schemes. The success of our algorithm on synthetic data is demonstrated and numerical results based on using the algorithm as a tool for exploring estimation performance is presented, as well as results based on using the algorithm to study the well-posedness of the problem, and the effects of fine-scale variations on coarse scale estimates. Examples based on analytical results that further the understanding of these issues are also presented. The results suggest the use of inhomogeneous spatial scales as a possible way of overcoming ill-posedness at points far away from the boundary. In dieser Arbeit stellen wir ein Verfahren zum Schätzen der Leitfähigkeit in einem abgeschlossenen zweidimensionalen Gebiet mit verschiedenen räumlichen Auflösungen bei gegebenen Randerregungen und -messungen vor. Wir formulieren das Problem als Maximum-Likelihood-Schätzproblem und geben einen Algorithmus an, der aus einer Folge von Schätzern auf immer kleiner werdenden Gittern besteht. Unter Ausnutzung der physikalischen Struktur haben wir das Problem auf jedem Gitter in zwei lineare Teilprobleme aufgeteilt, die jeweils mit Hilfe von parallelisierbaren Relaxationsverfahren gelöst werden. Wir wenden unseren Algorithmus erfolgreich auf synthetische Daten an und präsentieren numerische Ergebnisse, die auf dem Einsatz des Algorithmus als Hilfsmittel zur Untersuchung der Güte der Schätzung, der Gutartigkeit des Problems und der Auswirkungen von Variationen auf einem feineren Gitter auf den Schät

关键词： Multi-resolution maximum likelihood estimation partial differential equations Gauss-Seidel relaxation schemes Cramer-Rao bound

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AN EIGENSTRUCTURE APPROACH FOR THE RETRIEVAL OF CYLINDRICAL HARMONICS

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SIGNAL PROCESSING 1987年第2期13卷 121-139页

作者： TEWFIK, AH LEVY, BC WILLSKY, AS Laboratory for Information and Decision Systems and The Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

In this paper, we present a high resolution spectral estimation method for 2-D isotropic random fields with covariance functions equal to weighted sums of cylindrical harmonics. Such fields are often used to model some types of background noises in geophysics and in ocean acoustics. The approach that we present differs from previous 2-D spectral estimation techniques by the fact that we take maximal advantage of the symmetries implied by both the isotropy and the special covariance structure of these fields. Note that isotropy is the natural generalization to several dimensions of the 1-D notion of stationarity. Our approach is similar in spirit to 1-D harmonic retrieval techniques, such as the MUSIC method, which rely on an eigenanalysis of the covariance matrix. In the 2-D isotropic context, we begin with a Fourier series representation of an isotropic field with respect to the angle θ in a polar coordinate representation of the underlying 2-D space. We then obtain a spectral estimate by performing an eigenanalysis of the covariance matrix of samples of the zeroth-order Fourier coefficient process in order to extract the cylindrical harmonics. We also discuss the estimation of this covariance matrix and present examples to illustrate the high resolution and robustness properties of our procedure. Es werden einige neue Abtasttheoreme für isotrope Zufallsfelder und die zugehörigen Fourierprozesse entwickelt. Aufgrund dieser Theoreme wird ein Algorithmus vorgestellt, mit dem sich die zylindrischen Harmonischen eines isotropen Zufallsfeldes aus Werten der zugehörigen Kovarianzfunktion gewinnen lassen. Der vorgeschlagene Algorithmus nutzt die Eigenwertstruktur der Kovarianzmatrix des normalisierten Fourier-Koeffizientenprozesses nullten Grades; dieser Prozeß erweist sich als robust. Cet article propose une méthode d'estimation spectrale à grande resolution pour les champs isotropes aléatoires 2-D dont la fonction de covariance est égale à une somme d'harmoniques cylind

关键词： Isotropic random field Fourier coefficient process cylindrical harmonics eigenstructure analysis harmonic retrieval

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A UNIFIED FRAMEWORK FOR PRIMAL-DUAL METHODS IN MINIMUM COST NETWORK FLOW PROBLEMS

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MATHEMATICAL PROGRAMMING 1985年第2期32卷 125-145页

作者： BERTSEKAS, DP 1.Department of Electrical Engineering and Computer Science Laboratory for Information and Decision Systems Massachusetts Institute of Technology 02139 Cambridge MA USA

We introduce a broad class of algorithms for finding a minimum cost flow in a capacitated network. The algorithms are of the primal-dual type. They maintain primal feasibility with respect to capacity constraints, while trying to satisfy the conservation of flow equation at each node by means of a wide variety of procedures based on flow augmentation, price adjustment, and ascent of a dual functional. The manner in which these procedures are combined is flexible thereby allowing the construction of algorithms that can be tailored to the problem at hand for maximum effectiveness. Particular attention is given to methods that incorporate features from classical relaxation procedures. Experimental codes based on these methods outperform by a substantial margin the fastest available primal-dual and primal simplex codes on standard benchmark problems.

关键词： Primal-Dual Out-of-Kilter Relaxation Network Flow

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Realizations of focus invariance in optical-digital systems with wave-front coding

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APPLIED OPTICS 1997年第35期36卷 9157-9166页

作者： Bradburn, S Cathey, WT Dowski, ER []The authors are with the Imaging Systems Laboratory Opto-electronic Computing Systems Center Department of Electrical and Computer Engineering University of Colorado at Boulder Boulder Colorado 80309-0525.

We report experimental verification of an extended depth of focus (EDF) system with near-diffraction-limited performance capabilities. Dowski and Cathey [Appl. Opt. 34, 1859-1866 (1995)] described the theory of this system in detail. We can create an EDF system by modifying a standard incoherent optical system with a special cubic phase plate placed at the aperture stop. We briefly review the theory and present the first optical experimental verification of this EDF system. The phase plate codes the wave front, producing a modified optical transfer function. Once the image is transformed into digital form, a signal-processing step decodes the image and produces the final in-focus image. We have produced a number of images from various optical systems using the phase plate, thus demonstrating the success of this EDF system. (C) 1997 Optical Society of America.

关键词： extended depth of focus focus invariant optical-digital imaging systems image formation

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Hybrid phase-locked loop with fast locking time and low spur in a 0.18-μm CMOS process

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Chinese Physics B 2014年第7期23卷 748-753页

作者：朱思衡司黎明郭超史君宇朱卫仁 Beijing Key Laboratory of Millimeter Wave and Terahertz Technology Department of Electronic Engineering School of Information and ElectronicsBeijing Institute of Technology Advanced Computing and Simulation Laboratory (AχL) Department of Electrical and Computer Systems EngineeringMonash University

We propose a novel hybrid phase-locked loop （PLL） architecture for overcoming the trade-off between fast locking time and low spur. To reduce the settling time and meanwhile suppress the reference spurs, we employ a wide-band single-path PLL and a narrow-band dual-path PLL in a transient state and a steady state, respectively, by changing the loop bandwidth according to the gain of voltage controlled oscillator （VCO） and the resister of the loop filter. The hybrid PLL is implemented in a 0.18-μm complementary metal oxide semiconductor （CMOS） process with a total die area of 1.4×0.46 mm2. The measured results exhibit a reference spur level of lower than -73 dB with a reference frequency of 10 MHz and a settling time of 20 μs with 40 MHz frequency jump at 2 GHz. The total power consumption of the hybrid PLL is less than 27 mW with a supply voltage of 1.8 V.

关键词： phase-locked loop （PLL） fast locking time low spur complementary metal oxide semiconductor（CMOS）

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