Refine Your Search

Search Results

Viewing 1 to 7 of 7
Technical Paper

Direct Drive Friction Welding: A Comprehensive Mathematical Model

This paper presents a theoretical study on direct drive rotary friction welding process and investigates the possibility of producing an analytical solution of the heat transfer equation, both during the first part of heating process and the second part of the process when the operative temperature of the material at the end of the rod is assumed to be constant and equal to plasticization temperature. The solutions of the set of equations obtained have been compared with some experimental data present in literature [ 9 ] showing a fair agreement The burn-off volume (length in the case of a cylinder) can be estimated. The proposed method is simple, suitable for engineering calculations and can be used to predict the thermal evolution of welded elements and the burn-off volume, to reduce setup difficulties and to realize a more effective control on the process.
Technical Paper

An Overview of Scientific and Technical Literature on Coanda Effect Applied to Nozzles

In 1911 the first fundamental patent of Henry Coanda has been submitted. And 2011 is the centenary of this event for aeronautic history. This paper presents a general review of applied research about Coanda effect nozzles, starting from earlier Coanda works to today's applications. Coanda effect based nozzles are considered, looking at the nozzles which can produce an effective angular deflection of a jet and in particular of a synthetic jet produced by two or more jets.
Technical Paper

MAAT Cruiser/Feeder Project: Criticalities and Solution Guidelines

MAAT project is a large airship project presented to the last European 7 Framework Program Transport including Aeronautics 2011 deadline. MAAT project is an airship based cruiser-feeder transport system. This paper analyzes the criticalities of the project and the way to upfront these problems which have different natures and possible solutions. Most important criticalities are analyzed both on a methodological point of view and on a direct point of view. Enhanced design methodologies are analyzed in depth to analyze problems, upgrade the project design status continuously and to examine different design options and solutions. An innovative design method has been defined to avoid that problems can produce show stoppers and minimize time delays during project definition.
Technical Paper

MAAT Cruiser/Feeder Airship: Connection and Passenger Exchange Modes

In the general framework of the EU FP7 MAAT project, a novel green air transport architecture is under development. The paper presents the possible architectures for the cabin connections and the transfer modalities for people, crew and freight, for to the European project MAAT. Different architectures have been evaluated setting out to cover the structural and propulsive needs and to enable the transport modes between the Cruiser and the Feeders. The different possibilities are discussed conceptually, by considering the advantages and disadvantages of the presented configurations. The bases for future detailed design and research are established, as through such conceptual study the main parameters are identified and found to affect the general design of both airships and their operability. The aim of this paper is to specify the necessary elements, which are necessary to perform the docking operation by taking into account the prescribed Feeder-Cruiser geometries.
Journal Article

Propulsion of Photovoltaic Cruiser-Feeder Airships Dimensioning by Constructal Design for Efficiency Method

The European project MAAT (Multi-body Advanced Airship for Transport) is producing the design of a transportation system for transport of people and goods, based on the cruiser feeder concept. This project defined novel airship concepts capable of handling safer than in the past hydrogen as a buoyant gas. In particular, it has explored novel variable shape airship concepts, which presents also intrinsic energetic advantages. It has recently conduced to the definition of an innovative design method based on the constructal principle, which applies to large transport vehicles and allows performing an effective energetic optimization and an effective optimization for the specific mission.
Technical Paper

Optimization of Airships with Constructal Design for Efficiency Method

It is possible to define a novel optimization method, which aims to overcome the traditional Multidisciplinary Design Optimization. It aims to improve Constructal design method to optimize complex systems such as vehicles. The proposed method is based on the constructal principle and it is articulated in different stages: 1 preliminary top-down design process to ensure that the full system has one of the best configurations for the specified goals (contour conditions for constructal optimization could be stated ensuring an effective optimization at full-system level). 2 constructal optimization of the elemental components of the system to maximize the system performances; 3 eventually a competitive comparison between different configurations choosing the better one. The definition of an optimized flying vehicle (an airship) has been produced an example of this improved design method with the objective of minimizing the energy consumption during flight.
Technical Paper

Design of ACHEON Thrust and Vector Propulsion System

This paper focuses on the calculation methodology of the thrust of a ACHEON propulsion system, which is based on Coanda effect deflection of thrust. It defines a calculation methodology based on integral equations. The proposed methodology allows an effective calculation of the performances and the force applied on the airplane by such a propulsion system. It will also allow an effective design of the nozzle system and will implement also internal elements with an accurate definition of frictional losses. Outstanding results have been obtained together with general rules for implanting ACHEON propulsion inside an aircraft.