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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.

An exhaustive model of Coandã effect has not been defined, and fundamental questions are still open. One of them is the influence of convective heat exchange on Coandã adhesion. This paper presents an even preliminary numerical study of this problem. It analyses the behaviour of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface. It approaches the problem by a set of CFD simulations, analyses previous hypotheses, which are based on Prandtl number, and evidences the need for a model that account Reynolds number. The performed simulations are still not sufficient for an exhaustive comprehension of Coandã effect in the presence of heat exchange phenomena. It allows producing some consideration that may help future scientific work in toward a better comprehension of these phenomena.

This paper presents the new Hydrogen Fire-safe Airship system that overcomes the limitations present in previous airships designs of that kind, when considering their functioning at advanced operative position. Hydrogen is considered to be more effective than helium because of its low-cost production by hydrolysis, which process is nicely driven only by the photovoltaic energy. This paper presents a novel architectural concept of the buoyant balloon designed to increase the fire related safety, when applying hydrogen as the buoyant gas. The proposed buoyant volume is designed as a multi-balloon structure with a naturally ventilated shape, to ensure that hydrogen cannot reach the dangerous concentration level in the central airship balloon. This concept is expected to be the start of a novel hydrogen airship type, to be much safer than preceding ones.

This paper explores a novel structural design concept for a demonstrator of a high altitude photovoltaic feeder airship. The presented structural design concept aims to minimize the use of strategic materials in the structure of the airship, but also to maximize the ease of construction of the structure. The proposed design concept and method an effective analysis of historic airship structures considering their efficiency vs. weight and desired performances. By this analysis a novel structural design has been defined to reach the ambitious goal of a lighter and cheaper structure concept which can ensure comparable performances with traditional rigid airships. A discoid shaped airship with a central column has been taken into account. Structural calculations and constructive design has been presented in depth.

This paper presents an accurate analysis of an innovative high altitude platform with an unconventional ellipsoidal shape during the most critical operation. The airship is designed accordingly to the specifications, which have been analyzed in terms of the required CONOPS (Concepts of Operations) which are associated with the proposed High Altitude Pseudo-Satellite (HAPS) technology and special operations and to analyze the operational scenarios. An innovative cruiser feeder system is defined and studied. The CONOPS includes communications relays, support of intelligence, surveillance, target acquisition monitor “mobile targets”, and reconnaissance, including long-range ISTAR missions performed by the feeder, combining satellite vision and HAPS vision for a forest fire, disasters, naval accidents, maritime and ground borders.

This paper presents a model of energetic consumption and photovoltaic production for a large airship which acts as feeder connecting the ground with a large cruiser. The analysis of energy needs and productivity allows defining both an ideal sizing and operative mission profiles. The specialised mission of this airship is to ascent and descent. It includes also the connection with the airport buildings on the ground and with the cruiser at high altitude. Photovoltaic production has evaluated in terms of hydrogen and electric propulsion. They have estimated both and a calculation methodology has proposed. The evaluation has supported by CFD evaluations on aerodynamic behaviour of the system at various altitudes.

Environmental and economic issues related to the aeronautic transport, with particular reference to the high-speed one are opening new perspectives to pulsejets and derived pulse detonation engines. Their importance relates to high thrust to weight ratio and low cost of manufacturing with very low energy efficiency. This papers presents a preliminary evaluation in the direction of a new family of pulsejets which can be coupled with both an air compression system which is currently in pre-patenting study and a more efficient and enduring valve systems with respect to today ones. This new pulsejet has bee specifically studied to reach three objectives: a better thermodynamic efficiency, a substantial reduction of vibrations by a multi-chamber cooled architecture, a much longer operative life by more affordable valves. Another objective of this research connects directly to the possibility of feeding the pulsejet with hydrogen.

This paper presents a comparison between different hypotheses of propulsion of a spherical UAS. Different architectures have been analyzed assessing their specific aerodynamic, energetic, and flight mechanics features. The comparison has been performed assuming the robustness of flight control in different wind conditions, defining for each the specific operative ranges, mission profiles, and energy assessment. An effective energy assessment and comparison against a commercial UAS has been produced. Even if the paper considers a preliminary simplified configuration, it demonstrates clearly to be competitive against traditional quadcopters in a predefined reference mission.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method.

This paper starting by a previous mathematical model of rotary friction welding by the same authors defines a predictive methodology for a faster setup of rotary friction welding operations by thermal concentrated parameter model which describes temperature as a function of three elemental parameters: time, pressure and torque. It describes present a specific thermal method of calculation and verifies it by experimental data using a very simple experimental setup.

This paper analyzes the use of a recently patented 2D nozzle, which is able to produce a jet deviation depending on momentums of incoming jets and nozzle geometry. The considered nozzle architecture is a general-purpose fluid dynamic application. The research activity presented in this paper aims to verify the suitability of this nozzle architecture for aerial propulsion and in particular for small electric UAVs. This nozzle requires two primitive fluid streams, which produce a variable orientation synthetic jet. This preliminary feasibility study is related to a configuration propelled by two commercial electric turbofans for RC models and small electric UAVs. It can be used for both shortening take off and landing operations if mounted in a vertical plane and for enhancing the horizontal maneuvering if mounted on a horizontal plane. The shape of the considered nozzle has not been geometrically optimized to maximize the jet deflection.

This paper presents the theoretic and numerical background of a recent patent about an innovative Coanda Effect application. This innovative jet is designed to enhance the controllability of the system and to encompass static deflection of the fluid jet but especially the dynamic variation of the Coanda deflection with a very low inertia. This innovative nozzle is formerly named H.O.M.E.R., acronym of “High-speed Orienting Momentum with Enhanced Reversibility”. H.O.M.E.R. constitutes an application based on a dual propeller system. It explains how a vector controllable flux can be produced, with the ability to change angular position dynamically as a function of momentum (or velocity) of the two primitive streams. CFD based simulation in a configuration is provided and main calculations are produced to define the control model. Nozzle design guidelines are provided. The proposed system can be used both for aeronautical naval propulsion and industrial applications.

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.

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.

This paper presents and investigates different passive methods for reducing the notorious instability of discoid aerial vehicles. Presented methods are completely passive and involve elementary causes such as aerodynamic forces and gravitational effects. Four different system attitude control methods are presenting for different shapes and constructive solutions…

The MAAT project (Multibody Advanced Airship for Transport) aims to investigate aerial transportation possibility by airship based cruiser-feeder system. MAAT is composed by two modules: The cruiser, named PTAH, (acronym of Photovoltaic Transport Aerial High altitude system); the feeder, named ATEN (Aerial Transport Elevator Network feeder), is a VTOL system (Vertical Take Off and Landing) which ensure the connection between the cruiser and the ground. They can lift up and down by the control of buoyancy force and displace horizontally to join to cruiser.

This paper presents a novel concept of acclimatized container to increase people comfort in case of temporary housing. It is based on the ZEBRA concept (Zero Energy Building Renewable Addicted) concept studied by Università of Modena e Reggio Emilia. The original concept developed for industrial building has been extended to mobile metallic housing systems such as the containers transported by trucks which are used for troops and military command during field operations. This system does not require any external source of energy. It requires only the presence of a water well or drilling a hole to place inside a closed loop exchanger which is used to stabilize temperature of internal water which is used as a dynamic thermal barrier which maintains in the wellness conditions inside the mobile housing equipment. Energetic costs of this system are related only to the very reduced energy necessary for water pumping operations.

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.

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.

This paper presents a mathematical model of the vertical forces acting on an airship during vertical motion. The main effort is the definition of an airship model, which move only vertically by ballast, and buoyancy effects, with a much reduced energy consumption for take-off and landing operations. It has been considered a disc-shaped airship, which can operate using the open balloon airship architecture defined to operate safely with hydrogen. This architecture does not require internal ballonets, because of the connected increased fire dangers that they create even if vented. Several models of airship based on vertical forces have been presented in literature. They often consider only the US or International Standard Atmosphere models and they neglect effects of weather conditions. The latter are connected with the location and with the season.