Design Of Fuel System Research Articles

Optimization of Aircraft Fuel Systems Considering Fluid Dynamics Principles

The fuel system is the lifeline of any aircraft, pivotal for its operation and future advancements. This study delves into aircraft fuel system design methodologies, aiming to streamline development processes. Through optimization and matrix methods like the morphological matrix, Saab Aerospace pioneer’s conceptual designs. These methods automate development and deepen our understanding of how top-level requirements impact engineering details. Quantifying matrices opens doors to design optimization and probabilistic design. Furthermore, a systematic approach to simulation modeling minimizes development time, leveraging parallel development and collaborative engineering. With stakeholder expectations in mind, experience gleaned from projects like the Gripen fuel system shapes an overarching process for future endeavors. This journey promises to reshape aircraft fuel system design, ensuring each drop of fuel propels us towards boundless horizons. Key Words: Aerospace engineering, Fuel system, Optimization techniques, Matrix methods, Simulation models, Conceptual design, System integration, Aircraft performance, Fuel tank configurations, Operational flexibility, Gripen Fuel, DSM- Design Structure Matrix

A fine pore-preserved deep neural network for porosity analytics of a high burnup U-10Zr metallic fuel

U-10 wt.% Zr (U-10Zr) metallic fuel is the leading candidate for next-generation sodium-cooled fast reactors. Porosity is one of the most important factors that impacts the performance of U-10Zr metallic fuel. The pores generated by the fission gas accumulation can lead to changes in thermal conductivity, fuel swelling, Fuel-Cladding Chemical Interaction (FCCI) and Fuel-Cladding Mechanical Interaction (FCMI). Therefore, it is crucial to accurately segment and analyze porosity to understand the U-10Zr fuel system to design future fast reactors. To address the above issues, we introduce a workflow to process and analyze multi-source Scanning Electron Microscope (SEM) image data. Moreover, an encoder-decoder-based, deep fully convolutional network is proposed to segment pores accurately by integrating the residual unit and the densely-connected units. Two SEM 250 × field of view image datasets with different formats are utilized to evaluate the new proposed model’s performance. Sufficient comparison results demonstrate that our method quantitatively outperforms two popular deep fully convolutional networks. Furthermore, we conducted experiments on the third SEM 2500 × field of view image dataset, and the transfer learning results show the potential capability to transfer the knowledge from low-magnification images to high-magnification images. Finally, we use a pre-trained network to predict the pores of SEM images in the whole cross-sectional image and obtain quantitative porosity analysis. Our findings will guide the SEM microscopy data collection efficiently, provide a mechanistic understanding of the U-10Zr fuel system and bridge the gap between advanced characterization to fuel system design.

Design and Implementation of a Diagnostic Solid Propellant Fuel System Based on Laser Illuminator

Design and Implementation of a Diagnostic Solid Propellant Fuel System Based on Laser Illuminator

Wide-body aircraft fuel jettison system design and analysis

In order to design the highly integrated fuel jettison system, the hydrodynamic performance design flow chart for the highly integrated fuel system has been proposed, and the 1-D fuel line network performance model has been developed. An innovative fuel jettison system for wide-body aircraft has been designed. The system performance has been simulated and analyzed. The results show that the proposed flow chart can be used for the highly integrated fuel system design, and the fuel jettison performance requirements can be met. The system parameters including the wing tank main pump characteristic, the flow area of the orifice set in the fuel line connecting the feeding line and the refueling line, and the flight height have significant effects on the fuel jettison performance. Besides, the aircraft total fuel jettison performance is also affected by the central tank override pump characteristic, the engine fuel consumption, and the flow resistance of fuel line network.

Maritime LNG fuel systems for small vessels—A survey of patents

The goal of the Paris agreement (2015) is to achieve a climate-neutral world by mid-century. For maritime transport, the goal is a 50 % reduction of greenhouse gas emissions by 2050. This may be achieved using low and zero-emission fuels. LNG is a well-known low-carbon fuel for some ship types, but for application to medium to small-sized vessels, more cost-effective, compact, and operational robust solutions must be available. This paper discusses patented LNG fuel system designs and gives a qualitative evaluation of them with respect to their application to this ship segment. The use of a pressure build-up unit in combination with nitrogen injection, and/or heating of the LNG during bunkering, is suggested to be a feasible solution. Another aim of this paper is to highlight the role of patents within this area and contribute to the prevention of patent infringement.

Fuel System Design and Validation for UAV

The main goal is to develop a simple fuel system for a UAV (Unmanned Aerial Vehicle), as well as to check and validate whether the simulation and theoretical values are within an acceptable range. The fuel system of Lakshya is studied as a baseline reference model. Lakshya is a remotely piloted high-speed target drone system which is used to perform discreet aerial reconnaissance of battlefield and target acquisition. Flowmaster is a 1-Dimensional (1-D) Computational Fluid Dynamics (CFD) tool which is used for modelling and analyzing fluid mechanics in simple and complex piping structures as well and duct components of any scale. The fuel system of Lakshya is modelled in Flowmaster software with some modifications. The losses across each component are calculated theoretically and recorded. The losses are simulated on Flowmaster and the results are analyzed. The benefits of using Flowmaster simulation software are highlighted.

Analysis Methodology of Unusable Fuel Supply for Large Rotorcraft Airworthiness Certificate

The unusable fuel quantity plays a key basis for calibration of aircraft fuel gauge and fuel measurement system. Using large helicopter fuel tanks as case study, the paper described airworthiness requirements for fuel system design and current research development. In particular, the paper presented an analysis method can be utilized and referenced as means of compliance for airworthiness requirements. This method will reduce the qualification time and save money for physical and dynamic bench test/flight test in the future.

The Research of Aircraft Fuel System Icing Test

When a civil aircraft is flying in high altitude and low temperature environment, once the fuel feed system freezes, the fuel pressure and flow of engine and APU will decrease, resulting in the loss of aircraft power and even the occurrence of flight accidents. In this paper, the icing test platform of aircraft fuel system is set up, the test configuration and measurement system design method are given. By carrying out icing test of a certain type of fuel system, the test results show the safety and rationality of the aircraft fuel system design and test rig design, so as to provide guidance and reference for the implementation of icing test of aircraft fuel system.

Predicting the certification basis for airliner air-to-air refuelling

Abstract The premise is that in the future civil Air-to-Air Refuelling (AAR) will become an economic necessity if popular mass air travel is to continue. What is attempted is to provide a contemporary view of how such future operations could be safely undertaken. The intention is to predict the certification basis for demonstrating safe AAR operation of Cruiser-Feeder concepts. The necessary systems and aircraft functions are treated very much as they are today when civil certifying a large aeroplane type. The compliance demonstration required for environmental conditions, flight envelope, systems providing the necessary functionality, structural integrity, weight and balance are discussed. Applicable existing civil certification requirements are identified and where necessary expanded in scope to accommodate AAR operation. Where contemporary material does not supply appropriate guidance then corresponding safety criteria are proposed to address the deficiency. Lessons learnt from military AAR include the drive for interoperability. This has resulted in extensive efforts to standardise equipment and systems, which are equally applicable to civil AAR. Extremely useful advisory material exists, ranging from flight testing techniques to related safety. The importance of ensuring the consistency of failure condition categorisation at system and aircraft level is highlighted. The treatment of failures when two aircraft are in close proximity is something not considered by civil functional hazard analysis. The concept of AAR as an additional flight phase is introduced and affected system safety analyses identified. Examples of failure conditions that are not catastrophic at system level, but potentially could be at aircraft level during AAR are provided. Rendezvous scenarios are described to illustrate their influence on the certification basis. Combining such considerations with the factors that influence aircraft design leads to ramifications for handling qualities, performance and fuel system design. A viable and certifiable AAR configuration is consequently proposed. Consideration is given to treating operational certification in a progressive manner similar to existing LROPS (Long Range Operations).

Fuel System Configuration and Restructuring of MALE and HALE UAV

To meet the demand for long-endurance capabilities,MALE (medium-altitude long-endurance) and HALE (high-altitude long-endurance) UAVs are generally equipped with wing tanks to increase fuel loads. MALE and HALE UAVs use relatively larger aspect ratio wing to provide larger wing area and smaller wing thickness, so that the relative thickness of wing tank is smaller and its center of gravity is further away from the aircraft center of gravity, and the moment of inertia is greater. As a result of aerodynamic and structural arrangement, the horizontal and vertical manipulation of safety control and balance of such UAVs is very sensitive, thus making ​​higher demand for the fuel system. This paper describes and summarizes the typical fuel system design of MALE and HALE UAVs for fuel transfer and restructuring design, primarily focusing on fault condition, reconfiguration and the center of gravity control, and providing reference for fuel system design.

Development of Mathematical Model and Analysis of Characteristics of Gas Dampener for Power Plant Fuel Main Line

Providing stability and dynamic quality of fuel systems is very important problem when developing and during operation of power plants in many applications. For example, it is critical issue for longitudinal stabilization of launch vehicles (pogo attenuation). One of effective ways to provide rocket longitudinal stability is installation of a pogo suppression device (PSD) in the feed line. The paper presents a mathematical model of the gas PSD, its transient and frequency responses that can be used for the fuel system design. For developing mathematical model of the PSD, analytical methods and numerical simulation were applied, the software packages MatLab/Simulink and AMESim being used. The PSD input acoustic admittance was calculated. The developed model of the gas PSD can be used in the mathematical model of the fuel line when solving problem of longitudinal stability of launch vehicles and other issues of power plants design.

Liquid hydrogen fuel system design and demonstration in a small long endurance air vehicle

Abstract Autonomous systems have advanced substantially, yet on-board energy capacity still constrains endurance. Liquid hydrogen (LH2) fuel storage coupled with a high efficiency fuel cell may offer greater endurance. An LH2 storage system has been developed, featuring a lightweight dewar with active pressure control. The dewar has 20.46 L internal volume, yielding ≤7.6 kWh kg−1 specific energy and ≤1.2 Wh L−1 energy density (LHV basis) depending on fuel withdrawal rate and ambient conditions. It demonstrated 48 h continuous flight in the Naval Research Laboratory's Ion Tiger unmanned air vehicle, which is ∼85% longer than prior gaseous hydrogen (GH2) fueled flights, with the same dry mass as the GH2 system. Design considerations included matching the LH2 evaporation rate and variable consumption rate, and satisfying constraints imposed by the existing aircraft. Heat transfer models were used to design for low dewar heat leak, which is necessary to balance evaporation and consumption. The heat leak depends on ambient temperature, with evaporation ranging from 16 g h−1 at 240 K to 29 g h−1 at 300 K, at 275 kPa storage pressure. The LH2/GH2/dewar system takes ≥4 h to reach thermodynamic equilibrium after fueling. LH2 can extend the endurance of small autonomous systems, but at the expense of greater design effort and reduced operational flexibility.

Simulation of Cavitation and Pressure Surge: An Engineering Approach

The prediction of the magnitude of the pressure surge in aircraft fuel systems is important from the standpoint of designing systems that will not exceed the maximum surge pressure allowed and also to determine the limit pressure so that lightweight systems can be designed. Because aircraft refueling systems are relatively low pressure, the formation of gaseous products, cavitation, introduces severe nonlinearity not only in the form of dampened pressures but also in decreased propagation speed. The linear relation between the bulk modulus, pressure, and density that exists in high-pressure systems is made nonlinear by the formation of gases. This paper describes a simulation method for predicting the pressure surge in aircraft fuel systems that is suitable for engineering purposes. A model for gas formation has been developed. The dynamic simulation is a relatively fine, one-dimensional, discrete distribution of the fluid solved with MacCormack’s predictor corrector technique. Simulation results are compared to actual fuel rig tests. There is a step-by-step description of how the simulation model was tuned to correlate with the measured data. After this, some practical uses of the model, actual simulations used for fuel system design, are presented.

Modeling and Simulation for Design and Testing of Direct Injection Gaseous Fuel Systems for Medium-Speed Engines

Modeling and Simulation for Design and Testing of Direct Injection Gaseous Fuel Systems for Medium-Speed Engines

The Design of HCNG Engine Fuel System with Making Hydrogen by Sliding Electric Arc

This paper will put forward a device installed into the fuel system, which can use the sliding electric arc to electrolyze the natural gas to make hydrogen and then blend them in the fuel pipe for final combustion. This device can help to make a new type of HCNG engine fuel system, which electrolyses the single fuel (natural gas) partly to make appropriate-rate hydrogen for combustion. And in this paper, this new fuel system will be described in detail. The picture of sliding electric arc is shown in the end of this paper.

Research and Design of Small-Engine LPG Motorcycle Fuel System

By the analysis and comparison of LPG motorcycle and LPG automobile, the similarities and differences of them are expounded. Based on the components and structure of LPG automobile fuel system, the LPG motorcycle gas phase positive pressure fuel system and LPG motorcycle liquid phase positive pressure fuel system are designed, and the advantages and disadvantages are analyzed and compared. The engine cylinder cover is enhanced and setted maze channels, so the liquid state LPG can be pre-heated using the remaind head of engine before enter the decompressor, the frozen of decompressor is solved effectively. The road trial and testing show that the LPG motorcycle liquid positive pressure fuel system is simple in structure, stabilize and reliable, the comprehensive performance can satisfied the demand of national standard.

A look at design and application of fuel cell systems

Over the past few years, the direct conversion of chemical into electrical energy via fuel cells has been at the center of attention of electrochemical research and technology development. This is due not only to the complexity of fuel cell reactions and the general awareness of the technological potential of fuel cells but is also a result of society's strive towards developing environmentally-friendly power generation. In the reaction between hydrogen and oxygen for example, the only chemical product is water. The fuel cell, initially developed in the sixties as an on-board power supply unit for spacecraft, has now found new applications in powering submarines, in decentralized power supply systems, in portable charging docks for small electronics and in sensor technology. In the quest for a highly efficient, emission-free drive system, the development of mobile automotive fuel cell units is proving to be quite promising. Fuel cell technology constitutes a highly varied field which extends from available fuels and their processing, through the fundamentals of electrochemical processes, especially electro-catalysis, right to the numerous new concepts in systems technology for complete fuel cell aggregates including the control of gas, water and heat management. Many publications now appear annually in this field. The number of patent applications, especially from the industrial sector, has also risen over the past ten years. However, this paper is related to the design and application of fuel cell systems. Key words: Design, fuel, cell systems, power generation.

Optimal Conceptual Design of Aircraft Fuel Transfer Systems

This paper describes early considerations that have to be made when designing an aircraft fuel system. Emphasis is placed on illustrating the impact of top-level aircraft requirements on low-level practicalities such as fuel system design. Choosing between concepts is one of the most critical parts of any design process. Different concepts have different advantages, and the concept that is the best choice is often dependent on the top-level requirements. This paper shows how optimization has been used successfully at Saab Aerospace as a tool that supports concept selection. The example studied is the design of a fuel transfer system for a ventral drop tank and the optimization results in different conceptual designs depending on the top-level requirements.

Fuel design study and optimization for PEACER development

In order to increase the transmutation capability for the Pb-Bi cooled burner, PEACER, metallic fuel rods (60U–30TRU–10Zr with Pb-bond in HT-9 clad) having a short (50 cm) active length with a large gas plenum have been designed with a peak design TRU burnup of 15%. A 17 × 17 square-lattice with relatively high pitch-to-diameter ratio was employed to reduce the actinide production and pumping load associated with the high-density coolant. Fuel rod failure modes are identified and fuel design criteria are established. A fuel rod design model, named as RODSIS, has been obtained by incorporating Pb properties and a cladding oxidation rate equation. A thermal analysis has been conducted for a fuel rod having peak-power based on a predicted power distribution and history during an equilibrium cycle. Taking into account the high coolant density, all fuel rods are fastened in the assembly using a stiff middle grid structure and softer end grids made of HT-9. Based on fuel rod thermal analysis results, a finite element analysis (FEA) has been conducted for both thermal and mechanical analyses of the middle grid structure. Furthermore, a fuel assembly static analysis has been conducted to determine the consequences of the axial loading caused by buoyancy and flow. The PEACER fuel system design was visualized by using a three-dimensional design and visualization software.

Fuel system design of the smart UAV considering operational reliability

PurposeTo set‐up a specific design procedure for the smart unmanned aerial vehicle (UAV) fuel supply system which has been developed by Korean Aerospace Research Institute, and to design it preliminarily with the fuel system requirement and target reliabilities.Design/methodology/approachThe fuel system layout and fuel tank were determined through consideration of total fuel volume, fuel flow rate, reliability, weight, centre of gravity, etc. In sizing of components such as booster pumps, jet pumps, piping system, vent subsystem, refuelling and defuelling subsystem, engine fuel flow requirement, pressure loss, component failure rate, weight and centre of gravity were considered. Finally, the reliability analysis of the preliminary designed fuel system was carried out.FindingsAccording to the reliability analysis and weight estimation results, it was confirmed that the proposed fuel system agreed well with the design specifications and target reliabilities required by the vehicle system.Research limitations/implicationsIn current preliminary design phase, the most important consideration is the reliability of the fuel system. Therefore, the weight estimation of the designed fuel system to meet this reliability requirement could not meet partially the system's requirements. In the next design step, the proper fuel system for weight reduction will be performed through an optimization process between weight and reliability.Originality/valueA specific design procedure components' sizing to meet system requirement target reliability for UAV vertical take‐off/landing was proposed.