Efficient Charging System for Hyperloop Application

Conventional transportation methods are a major contributor to the climate crisis and Hyperloop systems are a proposed form of novel transportation that can provide a fast and energyefficient alternative. However, current research in Hyperloop technology has neglected the development of the charging infrastructure to facilitate repeated and high-speed charging cycles that minimize battery degradation. To address this, an efficient charging system for Hyperloop application is presented in this paper. Starting with a pre-existing electric vehicle (EV) charging model in MATLAB Simulink, the design was validated and scaled for the Hyperloop application to support a Lithium Iron Phosphate (LiFePO4) battery pack with parameters of 800V and 185Ah. This model was used to test the performance of the proposed charger and observe battery degradation in a variety of scenarios. Upon testing, the system parameters were tuned to successfully charge the specified battery pack in 42 minutes with the potential to decrease the charge duration by up to four times by using a higher charging current. The design was then scaled down to supply a LiFePO4 battery pack with 6.6V and 2.3Ah, which could be built in hardware to safely test and validate the design. The results of the small-scale prototype model were then compared with the full-scale model results. This yielded the same charge curve characteristics with only a 6% difference in the voltage magnitude, thus validating the scalability of the charging system. Finally, to minimize the effects of battery degradation, a temperature control system was designed to keep the battery pack at its ideal temperature (25°C) and was simulated at extreme temperatures of -30°C and 45°C. The results of the temperature control system showed a 7.2% reduction in battery degradation when compared to a system without a temperature control system

Hyperloop: A Cybersecurity Perspective

Hyperloop is among the most prominent future transportation systems. First introduced by Elon Musk, Hyperloop concept involves novel technologies to allow traveling at a maximum speed of 1220km/h, while guaranteeing sustainability. Due to the system's performance requirements and the critical infrastructure it represents, its safety and security need to be carefully considered. In cyber-physical systems, cyberattacks could lead to safety issues with catastrophic consequences, both on the population and the surrounding environment. Therefore, the cybersecurity of all the components and links in Hyperloop represents a fundamental challenge. To this day, no research investigated the cyber security of the technology used for Hyperloop. In this paper, we propose the first analysis of the cybersecurity challenges raised by Hyperloop technology. We base our analysis on the related works on Hyperloop, distilling the common features which will be likely to be present in the system. Furthermore, we provide an analysis of possible directions on the Hyperloop infrastructure management, together with their security concerns. Finally, we discuss possible countermeasures and future directions for the security of the future Hyperloop design.Comment: 9 pages, 4 figures, 1 tabl

Compliant Air Skates, An Experiment

There is currently a gap in the market of train levitation systems: wheeled trains and MagLev trains exist, but none utilize the low friction and high efficiency aspect of trains levitated by air skates. An air skate, is an air bearing that uses a pressure difference along its annular body to create a thin flow of air which is strong enough to levitate the weight of the skate. We have designed a compliant air skate that can glide over 0.04[in] defects in surfaces without touching down. After having made compliant skirts out of fiberglass and silicone, our setup of three air skates was easily capable of levitating 300[lb] while maintaining 3[psi] evenly split at the skates with an equivalent air flowrate of 3 [ft^3/min]

Blast Effects on Hyperloop’s Cylindrical Thin-Shell Structures

Super-high-speed guided systems such as hyperloops and MagLev are highly at risk of cyber and physical threats from either natural or man-made hazards. This study thus adopts a nonlinear finite element method to investigate and analyse blast responses of a spatial thin-shell structure formed as an essential part of the Hyperloop tunnelling system. The thin-shell structure is a longitudinal cylindrical tube used in hyperloop rail concepts that will have the capability to carry passenger pods travelling at speeds in excess of 1000 km/h. A robust parametric study has been carried out on a thin-shell metallic cylinder in accordance with experimental results to validate the blast simulation modelling approach. In addition, case studies have been conducted to simulate the effects of varied charge loading (TNT equivalent) of 10 kg, 15 kg and 20 kg. Since the hyperloop system is in its development stages, potential design modifications to adjust the thickness of the thin-shell cylinder are also simulated. Our findings demonstrate that thicker walls of 30 mm yield almost negligible dynamic displacements with lower blast pressures. However, this modification can cause serious ramifications in terms of infrastructure costs. On this ground, venting ports for blast mitigation have been proposed to alter and alleviate blast effects on the tube deformations. The novel insights reveal that increased venting port sizes can significantly increase the impulse deformations of the hyperloop tube but are key in reducing blast pressures within the asset infrastructure. These findings will inform hyperloop engineers about potential design solutions to ensure safety and reliability of future hyperloop rail travels amid the risks and uncertainties of cyber and physical threats

System design of a high speed ground vehicle lifted by air bearings

In 2015, SpaceX announced an international competition for student teams to design and build prototype pods to compete on a one-mile test track at their HQ in Hawthorne, CA. The track would be contained in a partial vacuum tube, and student teams were given near free reign in their design and build process. Of considerable interest in Hyperloop development is what mechanism of lift it should use—magnetic levitation or air bearings. In this Thesis, a novel approach is taken to the system design of a pod capable of levitating itself with compressed air, or air bearings. By doing so, drag is essentially eliminated from the system, and the pod will be able to travel at very high speeds with little power requirements. Building a half-scale pod and testing it on the track is considered a feasible way to test air bearings at high velocities. Since that has never been done before, the main goal of this research is to design and build a pod capable of doing so, given the input parameters provided by SpaceX. The prototype pod detailed in this thesis has been designed and built, and will be tested on the SpaceX test track. A new air bearing design is proposed for future work. While the SpaceX competition gave motivation for this work, the research conducted in this thesis, including evaluation of various levitation and braking mechanisms, design methodology, and parameter design, are applicable to other engineering challenges.Mechanical Engineerin

Methodology for a Numerical Multidimensional Optimization of a Mixer Coupled to a Compressor for Its Integrationin a Hyperloop Vehicle

[EN] The current environmental concern has led both the industry and researchers to look for alternate means of transport. Amongst them, the hyperloop has become a quite promising idea. In order to overcome some of its limitations, including a compressor in its propulsive system has been investigated. In this paper, a strategy to improve the design of the mixer, which will blend the bypass and core streams coming out of the compressor, was addressed. Due to the lack of ad hoc compressors and the impossibility of experimental testing, a multidimensional optimization methodology with CFD tools was developed. A Taguchi DOE was employed for a preliminary 2D optimization from an initial geometry, whereas a numerical adjoint method was explored for the whole 3D mixer. By using this method, an initial decrease in the pressure drop of 16%16% was obtained with the 2D stage, whereas an additional 10%10% reduction was achieved in the 3D optimization. With this, the propulsive efficiency of the whole hyperloop system will be improved.Project supported by the "Agencia Valenciana de la Innovacio" and the European Regional Development Fund 2014-2020: INNEST/2021/221 and INNEST/2021/344. Borja Pallas was supported by "Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana DOCEMPR UPV program" from the regional government, Generalitat Valenciana co-funded by the European Social Fund.Galindo, J.; Dolz, V.; Navarro, R.; Pallás, B.; Torres, G. (2022). Methodology for a Numerical Multidimensional Optimization of a Mixer Coupled to a Compressor for Its Integrationin a Hyperloop Vehicle. Applied Sciences. 12(24):1-25. https://doi.org/10.3390/app122412795125122

Open-Source Conceptual Sizing Models for the Hyperloop Passenger Pod

Hyperloop is a new mode of transportation proposed as an alternative to California's high speed rail project, with the intended benefits of higher performance at lower overall costs. It consists of a passenger pod traveling through a tube under a light vacuum and suspended on air bearings. The pod travels up to transonic speeds resulting in a 35 minute travel time between the intended route from Los Angeles and San Francisco. Of the two variants outlined, the smaller system includes a 1.1 meter tall passenger capsule traveling through a 2.2 meter tube at 700 miles per hour. The passenger pod features water-based heat exchangers as well as an on-board compression system that reduces the aerodynamic drag as it moves through the tube. Although the original proposal looks very promising, it assumes that tube and pod dimensions are independently sizable without fully acknowledging the constraints of the compressor system on the pod geometry. This work focuses on the aerodynamic and thermodynamic interactions between the two largest systems; the tube and the pod. Using open-source toolsets, a new sizing method is developed based on one-dimensional thermodynamic relationships that accounts for the strong interactions between these sub-systems. These additional considerations require a tube nearly twice the size originally considered and limit the maximum pod travel speed to about 620 miles per hour. Although the results indicate that Hyperloop will need to be larger and slightly slower than originally intended, the estimated travel time only increases by approximately five minutes, so the overall performance is not dramatically affected. In addition, the proposed on-board heat exchanger is not an ideal solution to achieve reasonable equilibrium air temperatures within the tube. Removal of this subsystem represents a potential reduction in weight, energy requirements and complexity of the pod. In light of these finding, the core concept still remains a compelling possibility, although additional engineering and economic analyses are markedly necessary before a more complete design can be developed

Design and Optimisation of a Virtual Prototype of a Ground Transportation System at Very High-Speeds in Conditions Close to Vacuum

[ES] Hyperloop es considerado el quinto medio de transporte, después del coche, barco, tren y avión. Consiste en una capsula de levitación magnética que viaja dentro de un tubo en el que la presión de aire ha sido reducida. Entonces, la fricción con el suelo y resistencia aerodinámica son minimizadas, alcanzando ultra altas velocidades a nivel de tierra. Actualmente hay en desarrollo varios trenes maglev y conceptos hyperloop. La mayoría proponen levitar usando Suspensión Electromagnética (EMS). Zeleros, la compañía donde esta Tesis ha sido realizada, tiene una propuesta similar. Zeleros usa un EMS Híbrido (HEMS), combinando imanes y electroimanes para reducir los requerimientos de energía. Respecto a la propulsión, la propuesta es única ya que hace uso de un compresor de la industria aeroespacial. Simulaciones CFD prueban que usar un compresor reduce considerablemente la resistencia aerodinámica en el ambiente cerrado, ya que el efecto pistón es mitigado. Para el mismo tamaño de tubo y presión, un hyperloop con compresor requiere hasta 70 % menos potencia. En otros términos, si la misma potencia es instalada en el vehículo, el diámetro de la infraestructura puede ser 2.8 veces más pequeño. Esta Tesis desarrolla un simulador 0D para evaluar el rendimiento de la solución hyperloop propuesta. Resolver su aerodinámica requiere solucionar un fujo interno y externo de Fanno. El último combina efectos de Couette y Poisuille en un dominio anular. Así, se desarrolla un modelo simplificado para flujos de Fanno, acelerando así el modelado básico. Esta aproximación matemática incluye información de la velocidad de la pared y de la forma del dominio, evitando integrar un sistema de EDOs. La solución tiene una desviación en la ratio de presiones de 5 % respecto a CFD, y del 10 % en la longitud crítica. El simulador modela toda la termodinámica del vehículo, incluyendo el compresor, conductos, turbina, tobera y flujo externo. Este modelado es similar al del ciclo de Bryton, sin cámara de combustión. Además, se incluye un modelo para predecir la masa y longitud de la cápsula y sus componentes. Así, las pérdidas de fricción y requerimientos de potencia y energía son obtenidos. Estos resultados presentan una desviación máxima del 20 % respecto a CFD. Además, un proceso de optimización para encontrar la solución más eficiente se ha desarrollado con el código, para vehículos de 50 y 150 pasajeros. Se ha encontrado que es más beneficioso absorber menos gasto másico con el compresor, ya que la energía requerida para comprimir el flujo interno es más alta que las pérdidas en el canal externo. Comparando el consumo de energía específico de esta solución con otros medios de transporte, el hyperloop se encuentra cercano al rendimiento de los maglev. Éste es, también, entre tres y cinco veces más eficiente que los aviones. Además, es más competitivo que el avión en términos de velocidad media en una ruta hasta los 800 km. Por último, se desarrolla un modelo similar para un sistema de escala media. Este prototipo, cuya velocidad objetivo es de 500 km/h, es diseñado por Zeleros previo al sistema de escala real. Su simulador incluye además los efectos transitorios y la termodinámica del tubo, asumiendo una velocidad del sonido infinita. Gracias a este código, se puede obtener el rendimiento en una misión. Inicialmente, el prototipo incrementa la presión del tubo aguas arriba, y la reduce aguas abajo debido al efecto pistón, generando una velocidad inducida. Al final de la misión, el flujo puede ser transferido otra vez, y las presiones se equilibran otra vez. Este modelo también predice el par y potencia del motor eléctrico, además de los parámetros de la batería (voltaje, corriente y profundidad de descarga).[CA] Hyperloop és considerat el cinquè mitjà de transport, després del cotxe, vaixell, tren i avió. Consisteix en una càpsula de levitació magnètica que viatja dins d'un tub on la pressió d'aire es reduïda. Aleshores, la fricció amb el sòl i resistència aerodinàmica són minimitzades, aconseguint ultra altes velocitats a nivell de terra. Actualment hi ha en desenvolupament diversos trens maglev i conceptes hyperloop. La majoria proposen levitar usant Suspensió Electromagnètica (EMS). Zeleros, la companyia on aquesta Tesi ha sigut realitzada, té una proposta similar. En particular, el concepte de Zeleros utilitza un EMS Híbrid (HEMS), combinant imants i electroimants per reduir els requeriments d'energia. Pel que fa a la propulsió, la proposta és única, ja que fa ús d'un compressor de la indústria aeroespacial. Simulacions CFD proven que utilitzar un compressor redueix considerablement la resistència aerodinàmica en un ambient tancat, ja que l'efecte pistó és mitigat. Per a la mateixa grandària de tub i pressió, un hyperloop amb compressor requereix fins a 70 % menys potència. En altres termes, si la mateixa potència és instal·lada al vehicle, el diàmetre de la infraestructura pot ser 2.8 vegades més menut. Aquesta Tesi desenvolupa un simulador 0D per avaluar el rendiment de la solució hyperloop proposada. Resoldre l'aerodinàmica del hyperloop requereix solucionar un flux intern i extern de Fanno. L'últim combina efectes de Couette i Poiseuille en un domini anular. Així, es desenvolupa un model simplificat per a fluxos de Fanno, accelerant així el modelatge bàsic. Aquesta aproximació matemàtica inclou informació de la velocitat de la paret i de la forma del domini, evitant integrar un sistema de EDOs. La solució té una desviació a la ràtio de pressions de 5 % respecte a CFD, i del 10 % a la longitud crítica. El simulador modela tota la termodinàmica del vehicle, incloent-hi el compressor, conductes, turbina, tovera i flux extern. Aquest modelat es similar al del cicle de Bryton, sense càmera de combustió. A més, s'inclou un model per predir la massa i la longitud de la càpsula i els seus components. Així, les pèrdues de fricció i requeriments de potència i energia són obtinguts. Aquests resultats presenten una desviació màxima del 20 % comparat amb CFD. A més, un procés d'optimització per trobar la solució més eficient ha estat desenvolupat amb el codi, per a vehicles de 50 i 150 passatgers. S'ha trobat que és més beneficiós absorbir menys massa amb el compressor, ja que l'energia requerida per comprimir el flux intern és més alta que les pèrdues al canal extern. Comparant el consum d'energia específic d'aquesta solució amb altres mitjans de transport, el hyperloop és proper al rendiment dels maglev. Aquest també és entre tres i cinc vegades més eficient que els avions. A més, és més competitiu en termes de velocitat mitjana en una ruta fins a 800 km. Finalment, es desenvolupa un model semblant per a un sistema d'escala mitjana. Aquest prototip, la velocitat objectiu del qual és de 500 km/h, és dissenyat per Zeleros previ al sistema d'escala real. El seu simulador inclou a més els efectes transitoris i la termodinàmica del tub, assumint una velocitat del so infinita. Gràcies a aquest codi, es pot obtenir el rendiment en una missió. Inicialment, el prototip incrementa la pressió del tub aigües amunt, i la redueix aigües avall degut a l'efecte pistó, generant una velocitat induïda. Al final de la missió, el flux pot ser transferit una altra vegada, i les pressions s'equilibren una altra vegada. Aquest model també prediu el parell i potència del motor elèctric, a més dels paràmetres de la bateria (voltatge, corrent i profunditat de descàrrega).[EN] Hyperloop is considered the fifth means of transportation, after the car, boat, train and plane. It consists of a magnetically levitating capsule that travels within a tube in which the air pressure has been reduced. Thus, the ground friction and aerodynamic drag are minimised, reaching ultra high-speeds at ground level. Several maglev trains and hyperloop concepts being developed currently. Most of them propose levitating using Electromagnetic Suspension (EMS). Zeleros, the company where this Thesis was done, has a similar approach. It employs a Hybrid EMS (HEMS)In particular, the Zeleros approach employs a Hybrid EMS (HEMS), combining permanent and electromagnets to reduce energy requirements. As for the propulsion, the approach is unique as it uses a compressor from the aeronautical industry. CFD simulations prove that using a compressor considerably reduces the aerodynamic drag in the closed environment, as the piston effect gets mitigated. For the same tube size and pressure, a hyperloop with compressor requires up to 70 % less power. In other terms, if the same power is installed on the vehicle, the infrastructure diameter can be 2.8 times smaller. This Thesis develops a 0D simulator to evaluate the performance of the proposed hyperloop solution. Solving the aerodynamics of the hyperloop requires solving internal and external Fanno flows. For the latter, the flow combines Couette and Poiseuille effects in an annular domain. Thus, a simplified model for Fanno flows is developed to accelerate the basic modelling. This mathematical approach includes the information of the wall speed and the shape of the domain, avoiding integrating an ODE system. The solution has a deviation in the pressure ratio of 5 % and 10 % in the critical length regarding CFD. The simulator models all the vehicle thermodynamics, including the compressor, duct, turbine, nozzle, and external flow. This modelling is similar to a Bryton cycle, without a combustion chamber. Also, a model to predict the mass and length of the capsule and its components is included. Thus, the friction losses and the energy and power requirements can be extracted. These outputs are compared with CFD results, with a maximum deviation of 20 %. Moreover, an optimisation process is conducted with the code to find the most efficient solution for 50- and 150-passenger vehicles. It is found that shallowing less mass flow with the compressor is better, as the energy required to compress the internal flow is higher than the losses on the external channel. Comparing the specific energy consumption of this solution with other means of transportation, the hyperloop is close to the maglev performance. It is also between three and five times more efficient than aeroplanes. Furthermore, the hyperloop is more competitive than the plane in terms of average speed on a route, up to 800 km. The last part of this work develops a similar model for a middle-scale system. This prototype, which aims to reach 500 km/h, is being designed by Zeleros before the real-scale one. Its simulator also includes the transient effects and the tube thermodynamics, assuming an infinite sound speed. Thanks to this code, the performance in a mission is obtained. The prototype initially increases the upstream tube pressure and reduces the downstream one due to the piston effect, generating an induced speed. At the end of the mission, the flow can be transferred again, and the pressures equilibrate again. This model also predicts the electric motor torque and power and the battery parameters (voltage, current, and deep of discharge).Este trabajo ha recibido una subvención parcial del Ministerio de Ciencia, Innovación y Universidades bajo la ayuda “Doctorandos Industriales” número DI-17-09616.Lluesma Rodríguez, F. (2022). Design and Optimisation of a Virtual Prototype of a Ground Transportation System at Very High-Speeds in Conditions Close to Vacuum [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/19140

Modeling and Performance Evaluation of Electromagnetic Suspension Systems for the Hyperloop

In 2012, the founder of SpaceX, Elon Musk, proposed a new method of transportation known as the Hyperloop. The proposed system, which would serve as the fifth method of transportation, described the fundamental theory of traveling in a near-vacuum tube at high speeds in a pod-like vehicle. Since Musk made his proposal, various companies and universities have investigated the Hyperloop concept in order to make it a reality. Researchers in the engineering and scientific community are currently investigating an effective electromagnetic suspension system design for the Hyperloop. It is hypothesized that a passive magnetic levitation (maglev) suspension system, as similarly designed for maglev trains, can be properly modeled and designed to provide optimized performance results for the proposed transportation method. The electromagnetic suspension design will utilize a specific arrangement of permanent magnets known as the Halbach array. In introducing linear velocity to the magnets, they will induce eddy currents along a conducting surface, and as a result, will create a force of levitation that will sustain the full weight of the capsule. Researchers have also proposed that in using a method of active magnetic levitation, where angular velocity instead of linear velocity is applied to the arrangement of magnets, the electromagnetic suspension will have improved control in stabilizing the induced levitation force and in keeping the displacement gap between the Hyperloop capsule and the conducting track constant. In order to approach this engineering problem, a specific methodology composed of literature review, calculation analysis, simulation, and testing evaluation has been selected for the purpose of obtaining satisfactory results for the proposed electromagnetic suspension systems. Through literature review, the physical theoretical models behind the proposed technology will be fully investigated in order to properly apply them as the foundational architecture of the suspension system. A mathematical model of the proposed suspension system will be designed and tested through MATLAB, for comparing the theoretical models with experimental data of existing technologies. Furthermore, the simulation results will be observed and analyzed in order to properly evaluate the figures of merit of the electromagnetic suspension methods