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To 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.

The 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.

According 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.

In 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.

A specific design procedure components' sizing to meet system requirement target reliability for UAV vertical take‐off/landing was proposed.

THE FUEL SYSTEM is a simple state‐of‐the‐art system which is designed to minimise system maintenance and provide a very high probability of mission success. It requires no fuel management or manipulation of system controls during a normal mission. It is designed to use MIL‐J‐5624G, grades JP‐4 and JP‐5 turbine fuel.

Fuel measuring and control systems have become progressively more sophisticated as aircraft performance has been extended both in the number of operating regimes and in operational capability. The fuel tank arrangements for the conventional aircraft types of the pre‐supersonic era, both piston and jet‐engined, allowed fairly straight‐forward fuel gauging and management. The tank dispositions were usually in line from left to right across the span of the wing. The advent of the swept wing aircraft introduced the complexities of fore and aft fuel balance in order to limit excursions of the CG about aft of the centre of lift. At the same time the operating economics of both military and civil aircraft, with massive fuel rate demand, required the development of fuel management systems capable of measuring and indicating fuel consumption and quantities to higher orders of accuracy.

Explains the fuel system of the Boeing 777‐200 aircraft. Looks at the system’s features, the fuel feed, the fuel jettison and the flight deck displays in terms of the fuel system.

Discusses the requirements for refuelling civil airliners, particularly under pressure refuelling. Analyses the problems that can arise and demonstrates how advancing technology has changed the appearance and efficiency of many components, particularly with reference to the control panel. Describes in detail the workings of a typical system; aspects of control of fuel quantity in refuelling; refuel control panels; and fuel gauges, with particular reference to the Boeing 777.

CONTROL SYSTEM PHILOSOPHY THE prime functions of any engine control system arc to provide stable speed governing and protection against overstressing the engine. Speed control is usually effected by hydro‐mechanical or hydro‐electrical governing of the fuel flow; overstressing is normally avoided by limiting engine temperature, turbine entry temperature, pressure, overspeeding and acceleration.

This paper aims to present a knowledge-based fuel system, implementation and application, oriented towards its use in aircraft conceptual design.

Methodology and software tools oriented to knowledge-based engineering applications (MOKA) is used as a foundation for the implementation and integration of fuel systems.

Including fuel systems earlier in the design process creates an opportunity to optimize it and obtain better solutions by allocating suitable locations in an aircraft, thereby reflecting on the centre of gravity of the aircraft.

All geometries are symbolic, representing a space allocation inside the aircraft for the fuel system. A realistic representation of the real components could be realized in detail design.

Fuel weight is a significant part of take-off weight and decisive in aircraft sizing and range estimations. The three-dimensional geometry provides a better estimation of the volume that is available to allocate the necessary entities. It also provides fast measures for weight and balance, fuel capacity, relative tank positions and a first estimation of piping length.

Fuel systems appear early in the design process, as they are involved in several first estimations. By using a knowledge-based engineering approach, several alternatives can be visualized and estimated in the conceptual design process. Furthermore, using the weights and centre of gravity at different angles of pitch and roll of each fuel tank, the aircraft could be optimized for handling qualities by using automatically generated system simulation models.

DOWTY Equipment Limited began the study of fuel systems for gas turbines in 1944, following the adoption by the de Havilland Engine Company of the Dowty Live Line Pump as the most promising type for conversion to a fuel pump. The resulting co‐operation hd to a widening interest and in 1945 the first design schemes for a complete fuel system were initiated.

A conference at the Institution of Mechanical Engineers detailed many features concerned with fuel systems in airframes and the aspects of refuelling today's large‐capacity aircraft. The influence of the aircraft requirements on both civil and military aircraft fuel‐system specifications were dealt with, the former by British Aerospace Airbus.

Discusses part of a project conducted by the authors into the logistics planning and management and costs of supplying biomass fuels to biomass‐fired power stations in the UK. Defines biomass fuels and the reasons for the growth in interest in their use for electricity generation. The activities and parties involved in the biomass fuel supply chain are discussed together with the management of the chain in order to achieve smooth and consistent flow of biomass fuel to power stations. Explains the approach used to modelling the delivered costs of biomass fuels for four types of biomass fuel included in the project: forest fuel, short rotation coppice, straw and miscanthus. Comments are given on the environmental impacts of the fuel supply chains. The results indicate that straw supply systems are capable of producing the lowest delivered costs of the four fuels studied. Short rotation coppice and miscanthus, two new energy crops, are likely to have the highest delivered costs at present. This is due to the cost of growing these fuels and the financial incentives required by farmers to persuade them to grow these crops. Logistics costs (i.e. transport, storage and handling) are shown to represent a significant proportion of total delivered cost in biomass supply. Careful supply chain planning and logistics management will be of central importance to the success of the biomass industry.