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Records with Subject: Process Design
580. LAPSE:2023.23453
Techno-Economic Assessment of a Combined Heat and Power Plant Integrated with Carbon Dioxide Removal Technology: A Case Study for Central Poland
March 27, 2023 (v1)
Subject: Process Design
Keywords: Biomass, Carbon Dioxide Capture, CO2 enhanced geothermal systems, combined heat and power, negative emission technologies, supercritical CO2 power cycles, utilization and storage
The objective of this study is to assess the techno-economic potential of the proposed novel energy system, which allows for negative emissions of carbon dioxide (CO2). The analyzed system comprises four main subsystems: a biomass-fired combined heat and power plant integrated with a CO2 capture and compression unit, a CO2 transport pipeline, a CO2-enhanced geothermal system, and a supercritical CO2 Brayton power cycle. For the purpose of the comprehensive techno-economic assessment, the results for the reference biomass-fired combined heat and power plant without CO2 capture are also presented. Based on the proposed framework for energy and economic assessment, the energy efficiencies, the specific primary energy consumption of CO2 avoidance, the cost of CO2 avoidance, and negative CO2 emissions are evaluated based on the results of process simulations. In addition, an overview of the relevant elements of the whole system is provided, taking into account technological progress and tec... [more]
581. LAPSE:2023.23439
Urban Design with the Wind: Pedestrian-Level Wind Field in the Street Canyons Downstream of Parallel High-Rise Buildings
March 27, 2023 (v1)
Subject: Process Design
Keywords: high-rise building, pedestrian-level wind, street canyon, urban design, wind tunnel
We are investigating how to use urban design approaches to conduct the layout and basic design of newly-built high-rise buildings to reduce wind obstruction and create effective urban ventilation. Few studies have addressed this issue. This study analyzes the effects of high-rise building on pedestrian-level wind in downstream street canyons based on wind tunnel test results, and examines the suitability of an urban design specification. The height (H) of high-rise buildings and the airflow passage width (S) between adjacent high-rise buildings are key control factors for this issue; H/D = 3 and S/D = 1.125 are critical parameters and recommended values (D is the height of the downstream street blocks).
582. LAPSE:2023.23431
Anaerobic Co-Digestion of Cheese Whey and Industrial Hemp Residues Opens New Perspectives for the Valorization of Agri-Food Waste
March 27, 2023 (v1)
Subject: Process Design
Keywords: anaerobic digestion, bioenergy perspectives, cheese whey, industrial hemp, methane, residual feedstock, techno-economic assessment
Cheese whey (CW) and hemp hurds (HH) represent typically overabundant biowastes of food and agricultural production, and their circular management is crucial to improve both sustainability and profitability of the agri-food chain. By combining experimental biochemical methane potential (BMP) tests and literature data, the techno-economic aspects of a possible future bioenergy valorization of CW and HH through anaerobic digestion (AD) and co- digestion (coAD) were analyzed. Along the 42-days, BMP assays, CW, and HH alone rendered BMP values of 446 ± 66 and 242 ± 13 mL CH4·g VS−1, respectively. The application of coAD with CW and HH at a 70:30 ratio allowed to enhance the biomethane production by 10.7%, as compared to the corresponding calculated value. In terms of economic profitability, the valorization of HH as biomethane in a dual-purpose hemp cultivation could potentially enable net profits of up to 3929 €·ha−1, which could rise to 6124 €·ha−1 in case of coAD with CW. Finally, by pr... [more]
583. LAPSE:2023.23415
Inkjet 3D Printed MEMS Vibrational Electromagnetic Energy Harvester
March 27, 2023 (v1)
Subject: Process Design
Keywords: 3D printing, energy harvester, MEMS
Three-dimensional (3D) printing is a powerful tool that enables the printing of almost unlimited geometry in a few hours, from a virtual design to a real structure. In this paper, we present a micro-electromechanical energy harvester that utilized a 3D printed micromechanical structure combined with a miniature permanent magnet and a microelectronic coil towards a hybrid electromagnetic vibrational hybrid energy harvester. Various micromechanical structure geometries were designed, printed, and tested. The characteristic dimensions of the springs were from 200 m to 400 m and the total volume of the devices was below 1 cm3. The resonant frequencies (95−340 Hz range), as well as bandwidths (6−23 Hz range), for the developed prototypes were determined. The maximal generated output power was almost 24 W with a power density up to almost 600 W/cm3.
584. LAPSE:2023.23387
Optimal Design of Photovoltaic Power Plant Using Hybrid Optimisation: A Case of South Algeria
March 27, 2023 (v1)
Subject: Process Design
Keywords: hybrid optimisation, LCOE, optimal design, photovoltaic power plants, PV module reduction
Considering the recent drop (up to 86%) in photovoltaic (PV) module prices from 2010 to 2017, many countries have shown interest in investing in PV plants to meet their energy demand. In this study, a detailed design methodology is presented to achieve high benefits with low installation, maintenance and operation costs of PV plants. This procedure includes in detail the semi-hourly average time meteorological data from the location to maximise the accuracy and detailed characteristics of different PV modules and inverters. The minimum levelised cost of energy (LCOE) and maximum annual energy are the objective functions in this proposed procedure, whereas the design variables are the number of series and parallel PV modules, the number of PV module lines per row, tilt angle and orientation, inter-row space, PV module type, and inverter structure. The design problem was solved using a recent hybrid algorithm, namely, the grey wolf optimiser-sine cosine algorithm. The high performance fo... [more]
585. LAPSE:2023.23386
Analysis and Design of Coupled Inductor for Interleaved Buck-Type Voltage Balancer in Bipolar DC Microgrid
March 27, 2023 (v1)
Subject: Process Design
Keywords: bipolar DC microgrid, coupled inductor, interleaved-type DC–DC converter, LVDC distribution system, voltage balancer
A voltage balancer (VB) can be used to balance voltages under load unbalance in either a bipolar DC microgrid or LVDC (Low voltage DC) distribution system. An interleaved buck-type VB has advantages over other voltage balance topologies for reduction in output current ripple by an aspect of configuration of a physically symmetrical structure. Similarly, magnetic coupling such as winding two or more magnetic components into a single magnetic component can be selected to enhance the power density and dynamic response. In order to achieve these advantages in a VB, this paper proposes a VB with a coupled inductor (CI) as a substitute for inductors in a two-stage interleaved buck-type VB circuit. Based on patterns of switch poles under load variation, the variation in inductor currents under four switching patterns is induced. The proposed CI is derived from self-inductance based on the configuration structure that has a two-stage interleaved buck type and mathematical design results based... [more]
586. LAPSE:2023.23311
Generalized Design Approach on Industrial Wireless Chargers
March 27, 2023 (v1)
Subject: Process Design
Keywords: design methodology, electromagnetic fields, electromagnetic shielding, Energy Efficiency, wireless power transmission
The paper briefly discusses the most important standards and regulations established for high-power wireless power transfer systems and introduces the main issues concerned with the conceptual design process. It analyses the electromagnetic design of the inductive magnetic coupler and proposes key formulas to optimize its electrical parameters for a particular load. The method applies to both the resistive load and the battery charging. It also suggests basic topologies for conceptual design of power electronics and discusses its proper connection to the grid. The proposed design strategy is verified by experimental laboratory measurement including analyses of the leakage magnetic field.
587. LAPSE:2023.23310
Non-Salient Brushless Synchronous Generator Main Exciter Design for More Electric Aircraft
March 27, 2023 (v1)
Subject: Process Design
Keywords: autonomous systems, brushless synchronous generator, electric power generation, high speed generator
This paper presents a prototype of high speed brushless synchronous generators (BSG) design for the application in autonomous electric power generation systems (e.g., airplane power grid). Commonly used salient pole field of the main generator part of BSG was replaced with a prototype non-salient pole field. The main objective of the research is an investigation into the advantages and disadvantages of a cylindrical field of the main generator part of BSG over the original salient pole field. The design process of the prototype generator is presented with a focus on the electromagnetic and mechanical finite element method (FEM) analysis. The measurements of prototype and commercial BSG were conducted for the nominal speed of 8 krpm. The advantages and disadvantages of the proposed solution were established based on measurements in load and no-load conditions.
588. LAPSE:2023.23244
The Flow Characteristics of Supercritical Carbon Dioxide (SC-CO2) Jet Fracturing in Limited Perforation Scenarios
March 27, 2023 (v1)
Subject: Process Design
Keywords: flow field, jet fracturing, limited perforation, supercritical carbon dioxide
Supercritical carbon dioxide (SC-CO2) jet fracturing is a promising alternative for shale gas fracturing instead of water. However, most studies pay more attention to the fracture generation and ignore the flow characteristic of SC-CO2 jet fracturing in limited perforation scenarios. To accurately explore the flow field in a limited perforation tunnel, a numerical model of a SC-CO2 jet in a limited perforation tunnel before fracture initiation is established based on the corresponding engineering background. The comparison between the numerical simulation and experiments has proved that the model is viable for this type of analysis. By using the numerical method, the flow field of the SC-CO2 jet fracturing is analyzed, and influencing factors are discussed later. The verification and validation show that the numerical model is both reliable and accurate. With the dramatic fluctuating of turbulent mixing in a fully developed region, there is an apparent increase in the CO2 density and t... [more]
589. LAPSE:2023.23240
Design and Comparison of Resonant and Non-Resonant Single-Layer Microwave Heaters for Continuous Flow Microfluidics in Silicon-Glass Technology
March 27, 2023 (v1)
Subject: Process Design
Keywords: chip integration, microfluidics, microwave heating, silicon
This paper presents a novel concept for the co-design of microwave heaters and microfluidic channels for sub-microliter volumes in continuous flow microfluidics. Based on the novel co-design concept, two types of heaters are presented, co-designed and manufactured in high-resistivity silicon-glass technology, resulting in a building block for consumable and mass-producible micro total analysis systems. Resonant and non-resonant co-planar waveguide transmission line heaters are investigated for heating of sub-micro-liter liquid volumes in a channel section at 25 GHz. The heating rates of 16 and 24 °C/s are obtained with power levels of 32 dBm for the through line and the open-ended line microwave heater, respectively. The heating uniformity of developed devices is evaluated with a Rhodamine B and deionized water mixture on a micrometer scale using the microwave-optical measurement setup. Measurement results showed a good agreement with simulations and demonstrated the potential of micro... [more]
590. LAPSE:2023.23216
Adsorptive Biogas Purification from Siloxanes—A Critical Review
March 27, 2023 (v1)
Subject: Process Design
Keywords: adsorbents, biogas treatment, regeneration, siloxane concentrations, volatile methylsiloxanes
Siloxanes are among the most technologically troublesome trace compounds present in biogas. As a result of their combustion, hard-to-remove sediments are formed, blocking biogas energy processing devices and reducing the efficiency of biogas plants. The purpose of this study was to help investors and designers to choose the optimal technology for the adsorptive removal of volatile methylsiloxanes (VMSs) from biogas and to identify adsorbents worth further development. This paper critically reviews and discusses the state-of-the-art technologies for the adsorption removal of siloxanes from biogas, indicating potentially beneficial directions in their development and deficiencies in the state of knowledge. The origin of VMSs in biogas, their selected physicochemical properties, technological problems that they can cause and their typical versus limit concentrations in biogases are presented. Both the already implemented methods of adsorptive VMSs removal from landfill and sewage gases an... [more]
591. LAPSE:2023.23132
Parametric Process Design and Economic Analysis of Post-Combustion CO2 Capture and Compression for Coal- and Natural Gas-Fired Power Plants
March 27, 2023 (v1)
Subject: Process Design
Keywords: carbon capture and storage, coal-fired power plants, economic analysis, Energy, NGCC, post-combustion
For the envisaged large number of commercial-scale carbon capture and storage (CCS) projects that are to be implemented in the near future, a number of issues still need to be resolved, the most prominent being the large capital and operational costs incurred for the CO2 capture and compression process. An economic assessment of the capture and compression system based on optimal design data is important for CCS deployment. In this paper, the parametric process design approach is used to optimally design coal and natural gas monoethanolamine (MEA)-based post-combustion CO2 absorption−desorption capture (PCC) and compression plants that can be integrated into large-scale 550 MW coal-fired and 555 MW natural gas combined cycle (NGCC) power plants, respectively, for capturing CO2 from their flue gases. The study then comparatively assesses the energy performance and economic viabilities of both plants to ascertain their operational feasibilities and relative costs. The parametric processe... [more]
592. LAPSE:2023.23094
High Threshold Voltage Normally off Ultra-Thin-Barrier GaN MISHEMT with MOCVD-Regrown Ohmics and Si-Rich LPCVD-SiNx Gate Insulator
March 27, 2023 (v1)
Subject: Process Design
Keywords: dynamic RON, leakage current, MISHEMT, MOCVD-regrowth, normally off
A high threshold voltage (VTH) normally off GaN MISHEMTs with a uniform threshold voltage distribution (VTH = 4.25 ± 0.1 V at IDS = 1 μA/mm) were demonstrated by the selective area ohmic regrowth technique together with an Si-rich LPCVD-SiNx gate insulator. In the conventional GaN MOSFET structure, the carriers were induced by the inversion channel at a high positive gate voltage. However, this design sacrifices the channel mobility and reliability because a huge number of carriers are beneath the gate insulator directly during operation. In this study, a 3-nm ultra-thin Al0.25Ga0.75N barrier was adopted to provide a two-dimensional electron gas (2DEG) channel underneath the gate terminal and selective area MOCVD-regrowth layer to improve the ohmic contact resistivity. An Si-rich LPCVD-SiNx gate insulator was employed to absorb trace oxygen contamination on the GaN surface and to improve the insulator/GaN interface quality. Based on the breakdown voltage, current density, and dynamic R... [more]
593. LAPSE:2023.23043
Design Evaluation for a Finned-Tube CO2 Gas Cooler in Residential Applications
March 27, 2023 (v1)
Subject: Process Design
Keywords: experimental testing, finned-tube gas cooler, supercritical carbon dioxide
Towards the introduction of environmentally friendlier refrigerants, CO2 cycles have gained significant attention in cooling and air conditioning systems in recent years. In this context, a design procedure for an air finned-tube CO2 gas cooler is developed. The analysis aims to evaluate the gas cooler design incorporated into a CO2 air conditioning system for residential applications. Therefore, a simulation model of the gas cooler is developed and validated experimentally by comparing its overall heat transfer coefficient. Based on the model, the evaluation of different numbers of rows, lengths, and diameters of tubes, as well as different ambient temperatures, are conducted, identifying the most suitable design in terms of pressure losses and required heat exchange area for selected operational conditions. The comparison between the model and the experimental results showed a satisfactory convergence for fan frequencies from 50 to 80 Hz. The absolute average deviations of the overal... [more]
594. LAPSE:2023.23015
Effects of Vapor Pressure of Desiccant Solution on Mass Transfer Performance for a Spray-Bed Absorber
March 27, 2023 (v1)
Subject: Process Design
Keywords: Absorption, driving force, mass transfer, vapor pressure
The depression in vapor pressure caused by adding desiccant to liquid water can be regarded as the driving force for the dehumidification process. The vapor pressure depends on the temperature and the concentration. Therefore, the purpose in this study is to discuss the mass transfer performance affected by operating variables and to show that the vapor pressure is a key factor affecting the mass transfer performance for absorbing water vapor by triethylene glycol (TEG) solution. The experimental results showed that the mass transfer coefficients were decreased with increases in the temperature and increased with increases in the concentration, respectively, while the mass transfer coefficients were increased with increases in the vapor pressure depression. Although both the average error is within 5% among the mass transfer correlation involving the vapor pressure and that involving the temperature and the concentration in predicting the mass transfer coefficient, there are just two t... [more]
595. LAPSE:2023.23014
Influence of Leachate and Nitrifying Bacteria on Photosynthetic Biogas Upgrading in a Two-Stage System
March 27, 2023 (v1)
Subject: Process Design
Keywords: ammonia removal, biogas upgrading, biomethane, Carbon Dioxide, gas-liquid ratio, leachate, microalgae, photobioreactor
Photosynthetic biogas upgrading using two-stage systems allows the absorption of carbon dioxide (CO2) in an absorption unit and its subsequent assimilation by microalgae. The production of microalgae requires large amounts of nutrients, thus making scale-up difficult and reducing economic feasibility. The photosynthetic process produces oxygen (O2) (1 mol per mol of CO2 consumed), which can be desorbed into purified biogas. Two-stage systems reduce its impact but do not eliminate it. In this study, we test the use of landfill leachate as a nutrient source and propose a viable and economical strategy for reducing the O2 concentration. First, the liquid/gas (L/G) ratio and flow mode of the absorber were optimized for 20% and 40% CO2 with COMBO medium, then landfill leachate was used as a nutrient source. Finally, the system was inoculated with nitrifying bacteria. Leachate was found to be suitable as a nutrient source and to result in a significant improvement in CO2 absorption, with out... [more]
596. LAPSE:2023.22960
Energy Distribution of Optical Radiation Emitted by Electrical Discharges in Insulating Liquids
March 24, 2023 (v1)
Subject: Process Design
Keywords: electrical discharges, energy distribution, insulating liquids, optical radiation
This article presents the results of the analysis of energy distribution of optical radiation emitted by electrical discharges in insulating liquids, such as synthetic ester, natural ester, and mineral oil. The measurements of optical radiation were carried out on a system of needle−needle type electrodes and on a system for surface discharges, which were immersed in brand new insulating liquids. Optical radiation was recorded using optical spectrophotometry method. On the basis of the obtained results, potential possibilities of using the analysis of the energy distribution of optical radiation as an additional descriptor for the recognition of individual sources of electric discharges were indicated. The results can also be used in the design of various types of detectors, as well as high-voltage diagnostic systems and arc protection systems.
597. LAPSE:2023.22958
A Preliminary Techno-Economic Analysis on the Calcium Looping Process with Simultaneous Capture of CO2 and SO2 from a Coal-Based Combustion Power Plant
March 24, 2023 (v1)
Subject: Process Design
Keywords: calcium looping, Carbon Dioxide Capture, coal-based power plant, desulphurization, Technoeconomic Analysis
The increase of capital investments and operation and maintenance (O&M) costs represents a current limitation to the diffusion of carbon capture systems for the clean combustion of fossil fuels. However, post-combustion systems, such as calcium looping (CaL), for CO2 capture from flue gas are the most attractive carbon capture systems since they can be installed at new plants and retrofitted into existing power plants. This work investigates the pros and cons of employing a calcium looping system for CO2 capture and also as a desulphurization unit. A preliminary techno-economic analysis was carried out comparing a base case consisting of a coal-based power plant of about 550MWe with a desulphurization unit (Case 1), the same plant but with a CaL system added for CO2 capture (Case 2), or the same plant but with a CaL system for simultaneous capture of CO2 and SO2 and the removal of the desulphurization unit (Case 3). Case 2 resulted in a 67% increase of capital investment with respect t... [more]
598. LAPSE:2023.22929
Lightning Performance Evaluation of Italian 150 kV Sub-Transmission Lines
March 24, 2023 (v1)
Subject: Process Design
Keywords: backflashover rate, grounding system, lightning performance, Monte Carlo, sub-transmission lines
A significant majority of overhead transmission lines’ (OHLs) outages is due to backflashovers caused by direct lightning strikes: the realistic assessment of the lightning performance is thus an important task. The paper presents the analysis of the lightning performance of an existing 150 kV Italian OHL, namely, its backflashover rate (BFOR), carried out by means of an ATP-EMTP-based Monte Carlo procedure. Among other features, the procedure makes use of a simplified pi-circuit for line towers’ grounding system, allowing a very accurate reproduction of transient behaviours at a very low computational cost. Tower grounding design modifications, aimed at improving the OHL lightning performance, are also proposed and discussed.
599. LAPSE:2023.22921
Increasing the Device Performance of Recycling Double-Pass W-Ribs Solar Air Heaters
March 24, 2023 (v1)
Subject: Process Design
Keywords: artificial W-ribs, Heat-transfer efficiency, Nusselt number, power consumption, recycling solar air heater
The device performance of recycling double-pass solar air heaters with W-ribs by machining on both sides of the absorber plate is investigated experimentally and theoretically. It is emphasized that in comparing various design configurations, they should be compared for the increase of power consumption suffered by the air passing through the collector under the same air mass flow rate and working dimensions. Compared to those of the single-pass and flat-plate double-pass device, both effects of the external recycle and the artificial W-ribs by machining enhance the collector thermal efficiency in this study. This study proposes an optimal design of the recycling W-ribs double-pass device that is expected to consider the compensation between collector thermal efficiency improvement I W due to the external recycle and the increase of power consumption I P , W owing to pumping the air circulation in the two divided subchannels. The evaluation of a higher ratio of... [more]
600. LAPSE:2023.22905
Three-Dimensional Mathematical Model of the Liquid Film Downflow on a Vertical Surface
March 24, 2023 (v1)
Subject: Process Design
Keywords: dimensionless parameters, gas–liquid, interfacial surface, separation layer, velocity field
Film downflow from captured liquid without wave formation and its destruction is one of the most important aspects in the development of separation equipment. Consequently, it is necessary to create well-organized liquid draining in areas of captured liquid. Thus, the proposed 3D mathematical model of film downflow allows for the determination of the hydrodynamic parameters of the liquid film flow and the interfacial surface. As a result, it was discovered that the interfacial surface depends on the proposed dimensionless criterion, which includes internal friction stress, channel length, and fluid density. Additionally, equations for determining the averaged film thickness, the averaged velocity vectors over the film thickness, the longitudinal and vertical velocity components, and the initial angle of streamline deviation from the vertical axis were analytically obtained.
601. LAPSE:2023.22883
System Designs and Experimental Assessment of a Seven-Mode Vehicle-Oriented Hybrid Powertrain Platform
March 24, 2023 (v1)
Subject: Process Design
Keywords: electric vehicle, green energy, hybrid powertrain, mechatronics, pneumatic power
This study developed a mechatronics platform for a seven-mode vehicle-oriented powertrain system. The innovative “all-in-one” concept was used for flexibly arranging various power or energy sources to be combined for various hybrid powertrains. Hence, it significantly reduces the cost and human resources for evaluating new-type power systems or developed vehicle control strategies on the same experimental platform. In this study, three power sources were chosen for providing hybrid power. The first source is a 125 c.c. spark ignition (SI) engine, where a controllable throttle valve governs the output torque, while a fuel meter measures the consumed fuel. The second one is a 1.5kW hub motor, where a motor control unit (MCU) and a 48V lithium battery pack properly provide the required electric power. The third source is an air engine, where a 220V air compressor and other components provide the pneumatic power. For the experimental platform, a developed Matlab/Simulink package receives t... [more]
602. LAPSE:2023.22875
Ultracapacitors for Port Crane Applications: Sizing and Techno-Economic Analysis
March 24, 2023 (v1)
Subject: Process Design
Keywords: energy cost, energy storage system (ESS), peak shaving, ship to shore (STS) crane, Technoeconomic Analysis, ultracapacitor sizing
The use of energy storage with high power density and fast response time at container terminals (CTs) with a power demand of tens of megawatts is one of the most critical factors for peak reduction and economic benefits. Peak shaving can balance the load demand and facilitate the participation of small power units in generation based on renewable energies. Therefore, in this paper, the economic efficiency of peak demand reduction in ship to shore (STS) cranes based on the ultracapacitor (UC) energy storage sizing has been investigated. The results show the UC energy storage significantly reduce the peak demand, increasing the load factor, load leveling, and most importantly, an outstanding reduction in power and energy cost. In fact, the suggested approach is the start point to improve reliability and reduce peak demand energy consumption.
603. LAPSE:2023.22796
Investigation of the Process of Simple Distillation in Irrigated Pipe Elements
March 24, 2023 (v1)
Subject: Process Design
Keywords: Distillation, evaporator, mass streams, mass transfer, non-equimolarity, velocity profiles
In modern chemical and oil refining complexes, separation processes are among the most popular and energy-intensive. Installations for their implementation should be equipped with nodes for creating vapor (evaporators) and liquid (deflegmators) irrigation. Evaporators of any type (film, thermosiphon, gas lift, cubic) belong to this class of devices. For example, in cubic evaporators, the gas flow is completely formed from flux bubbles that originate on the heat-conducting surface and float in the volume of the cubic liquid located in the apparatus. Due to the accompanying mass exchange, the bubbles are enriched with volatile components during ascent and noticeably increase in volume, and the growth of the bubble is determined, among other things, by the total flow. At the same time, in real bubbling-type equipment, the total mass transfer surface exceeds the cross-section of the device itself by more than two orders of magnitude. Thus, according to, the ratio of the internal cross-sect... [more]
604. LAPSE:2023.22770
Conceptual Design Development of a Fuel-Reforming System for Fuel Cells in Underwater Vehicles
March 24, 2023 (v1)
Subject: Process Design
Keywords: Carbon Dioxide, fuel cell, fuel reforming, Methanol, underwater vehicle
An air-independent propulsion system containing fuel cells is applied to improve the operational performance of underwater vehicles in an underwater environment. Fuel-reforming efficiently stores and supplies hydrogen required to operate fuel cells. In this study, the applicability of a fuel-reforming system using various fuels for underwater vehicles was analyzed by calculating the fuel and water consumptions, the amount of CO2 generated as a byproduct, and the amount of water required to dissolve the CO2 using aspen HYSYS (Aspen Technology, Inc., Bedford, MA, USA). In addition, the performance of the fuel-reforming system for methanol, which occupies the smallest volume in the system, was researched by analyzing performance indicators such as methanol conversion rate, hydrogen, yield and selectivity, and reforming efficiency under conditions at which pressure, temperature, steam-to-carbon ratio (SCR), and hydrogen separation efficiency vary. The highest reforming efficiency was 77.7−... [more]