Hybrid Airship Research Articles

Development of attitude control system for hybrid airship vehicle

This paper documents and presents the development of attitude control system of Hybrid Airship Unmanned Aerial Vehicle (HAU) that should be able to change its attitude condition based on the response processed from the provided input. This is accomplished by data acquisition method that retrieves data from a flight controller and processes it into the control system without looking in deep on the mathematical model of the airship. Besides that, PID controller is used in order to create a good stable response for the hybrid airship. A working hybrid airship prototype was successfully developed and built, which is five meters in length and has four propellers that is symmetrically distanced to each other. A quadcopter attitude control mechanism is adopted into the hybrid airship to allow for good hovering capability and direct pure attitude control. Outdoor flight tests have been conducted to prove its stability in responding to attitude input given to the hybrid airship attitude controller. A data monitoring software is also written to make the data observation on the behaviour of the hybrid airship response to be easier and understandable. Result demonstrates that the hybrid airship does response to pitch, roll and yaw input from the operator, albeit the lack response stability and speed which can be improved in conservative continuation of research on the airship attitude control system.

Flight Performance Analysis of Hybrid Airship Considering Added Mass Effects

In this paper, an analysis is applied to a hybrid airship considering the added mass. First, based on the dynamic mesh technology, a computational fluid dynamics (CFD) method is employed to obtain the added mass coefficient matrix. Through a validation process using the 6:1 prolate spheroid, the 6 × 6 added mass matrix of hybrid airship is obtained. After a dynamic modeling, the equations of motion with added mass are developed. Through the linearization based on small perturbation, the linearized longitude model is used to simulate the dynamic response of a trim condition. The take-off and landing performance has been analyzed and affected by the added mass. The result shows an obvious vertical destabilizing trend on the hybrid airship dynamics due to the added mass and the inertial effect has little influence on the vehicle during the take-off and landing.

Conceptual Design of Low Altitude Unmanned Small Hybrid Airship

In the last two decades, popularity of Unmanned Air Systems (UAS) are at their peaks. Their capacities and abilities are advancing day by day in parallel with development of science and technology. They are doing almost everything what conventional aircrafts are doing except passenger transfer, for now. Despite an UAS can be controlled from thousands of miles away, they are still limited in range and endurance because of their energy storage capacities. Most of the energy sources of an aircraft is used against to gravitational force. However, Lighter Than Air(LTA) gases like helium, hydrogen etc. provides an option to aircrafts using lifting capacity of these gases and combination of lifting capacity of LTA gases and mechanical forces produced by engines allows engineers to create hybrid airships. Hybrid Airships gains flight altitude by using static lifting force of lighter than air gases in addition of the mechanical force which is produced by the propulsion system of the vehicle. Engines makes necessary maneuver with direction units to control the airship in all directions. Static lift from the LTA gases provide additional payload capacity to vehicle without consuming energy. Therefore, unlike the conventional aircrafts, hybrid airship has more flight duration than the others and more payload capacity. Aim of this work is, developing a low-cost small hybrid airship by using static lift force of the lighter than air gases and present to advantages of hybrid aircrafts.

Thermal performance analysis of a high-altitude solar-powered hybrid airship

Abstract The increasing application of hybrid airships which have been recently proposed as high altitude platforms, makes it necessary for research into the thermal performance of such airships that possess a photovoltaic module array(PVMA). In this study, a simplified thermal model of a high-altitude hybrid airship with a PVMA, was proposed that included direct solar, infrared, reflected, and scattered radiation and convective heat transfer. Based on computational fluid dynamics(CFD), a simulation methodology, using a user defined function(UDF) program, was introduced to investigate the PVMA's thermal effects on the hybrid airship. A ground experiment was also performed to validate this numerical method's effectiveness. Further simulations and discussion of temperature and velocity distributions of the hybrid airship's internal helium were conducted. The results showed that the PVMA atop the hull had large effects on the hybrid airship's thermal performance. The temperature distribution of the envelope varied greatly during the day and night because of the PVMA's influence as well as the internal helium flow. In addition, forced convection had little influence on the PVMA's output performance, which was analyzed in detail.

Unconventional hybrid airships design optimization accounting for added masses

This paper describes the implementation of a framework which can be used to optimize the external shape of an unconventional airship configuration. This framework includes the estimation of Added Masses (AM) which captures the contribution of the dynamic effect related to the acceleration of a body immersed in a fluid having a similar density to that of the body itself. A computationally efficient routine to compute AM has been implemented in a heuristic optimization loop based on a Particle Swarm Optimization (PSO) algorithm, and has been integrated into a simple model which provides hybrid airship's aerodynamics characteristics. As a case study, the take-off distance of a hybrid airship has been optimized by the methodology, and it is used to show the effect on the optimization loop and the errors arising from using conventional approximated AM evaluation methods. The proposed set of simulations clearly evaluates the errors expected on the unconventional airships performances when approximated methods are used in the evaluation of the AM.

Computational Fluid Dynamics (CFD) Study on a Hybrid Airship Design

The aerodynamic lift and drag performance is one of the important considerations for hybrid airship configuration design. In conjunction with this, simulation study of aerodynamic characteristics can certainly benefit the process of deriving the best possible configuration for hybrid airship design. The aim of this study is to investigate the trend of aerodynamic lift and drag performance for an airship design in different velocities, altitudes and design fineness ratio using the Star CCM+ analysis tool. The airship model applied in this case study is an approximate model of the Atlant-100 airship. It is found that the airship model with low design fineness ratio typically generates much better aerodynamic lifting force in comparison to those with high design fineness ratio. On the other hand, while the range of estimated drag coefficient values is found to be rather insignificantly different, the presence of effects from the design fineness ratio is still evident. Generally, high design fineness ratio for the airship model seems to produce much lower drag force.

Conceptual design and analysis of hybrid airships with renewable energy

An increasing focus on hybrid airships and the developments in renewable energies has allowed a methodology for conceptual design and analysis to be described. After a model presented and its aerodynamic characteristics obtained through a computational fluid dynamics method, two types of hybrid airships, solar powered at high altitudes and hydrogen powered for cargo, are demonstrated using a wing loading as their independent variable. Then the constraints determining the design point are presented. Parametric estimates of two types for component mass are then illustrated on distribution diagrams. And the sensitivity of wing loading and its effects on hybrid airships are discussed.

Optimization of solar-powered hybrid airship conceptual design

This paper aims to develop a high-altitude solar-powered hybrid airship, which combines aerodynamic lift and buoyancy with buoyancy force and cruises continuously. A multi-lobed configuration is employed and the solar irradiance and photovoltaic array model are proposed. After introducing all the parts mass of the hybrid airship and design procedure, an optimal problem with the constraint of energy and the equilibrium between buoyancy and weight are proposed. Through a hybrid optimization search method, the solution is obtained and the sensitivities of geographical location and seasons are discussed. The results show a comprehensive influence of the constraint both in latitude and wind field environment.

Aerodynamic and overall parameters analysis of buoyancy-lifting hybrid airship

In order to balance the aerodynamic performance and buoyancy-lifting characteristics of airship,to make full use of their advantages and to strengthen the controllability,a hybrid airship configuration which has combined envelopes that are based on high lift NACA airfoil was proposed. With computational fluid dynamics( CFD) and FLUENT computing modeling,the lift-drag characteristics,longitudinal static stability and buoyancy-lifting property under different velocities and attack angles of the airship were simulated,furthermore,its overall performance was evaluated and lastly it was compared with conventional airship. The results show that the airship configuration with combined envelopes has good aerodynamic performance and efficiency. It can produce three times aerodynamic lift than that of conventional airship under the same condition.When the magnitude of cruise velocity is greater than 26 m / s,hybrid airship begins to have a higher total lift efficiency and better buoyancy-lift property. Besides,the hybrid airship's size is smaller than conventional airship under the same design load,which contributes to increasing payloads. This can provide a reference for low-attitude large hybrid airship's research.

Design and Fabrication of a Winged Hybrid Airship Model for IIUM-LSWT

Wind Tunnel Testing on a subscaled model of a winged hybrid airship requires a faithful reproduction of all geometric details of actual airship. Due to huge volume of hull, geometrical parameters of such airships are quite different from that of an aircraft. In this article, a scheme for designing such models is described alongwith a review of different strategies available for manufacturing of its prototype wind tunnel model in IIUM low speed wind tunnel. Similar to aircrafts, major contributing factors for scaling, design and manufacturing of a subscaled model of hybrid airships are discussed. It is concluded that the required aerodynamic data will be the dictating factor for selection of the manufacturing method.

Method of parametric studies of computational models first approximation of the aircraft with aerostatic SUPPORT

In recent years, scientists of the leading countries of the World, designers, specialists of different industries are paying close attention to aircrafts lighter than air. These aircraft use much less fuel than similar planes and helicopters with load capacity, capable to transport heavy loads on thousands of miles away, with the possibility of landing on unprepared sites or hang in the air for a long time with a cargo during the construction works. In addition, they provide a significant increase in safety of the flight in their exploitation.One of the most promising types of airships are aircraft with aerostatic support (hybrid airships) using two principles generate lift: aerodynamic and aerostatic. They can incorporate the best qualities of the airplane (speed), the airship (large capacity and range), and helicopter (the possibility of implementing a short or vertical takeoff and landing).For the formation of aerodynamic lift of the aircraft needs a wing only. All other units of aircraft not involved in the creation of lift is desirable to place inside the wing. Therefore, for the further research we chose an aerodynamic scheme called "flying wing". This scheme is the most rational for using the force of the aerostatic lifting gas, which is located inside the wing.To solve the problem in the research we used the method of calculation of the aerodynamic characteristics of aircraft in the parameters of similarity, which allows estimating the aerodynamic behavior of the wing-form in design with linear edges. It is necessary to determine the optimal layout of the wing and its aerodynamic performance in conditions of using more force of aerostatic lifting gas, concluded in the interior of the wing.With an increase of the relative profile thickness from 8% to 30% the maximal aerodynamic efficiency will be reduced from 14 to 11 units. However, the loss of quality can be compensated to fill the inner cavity of the wing lifting gas. This makes an additional component of the aerostatic force. For example the model with the relative thickness profile of 30%, and aerostatic lift 171 kg is considering.Thus we had made the analysis of changes in aerodynamic and aerostatic characteristics of the computational model of the first approximation of the aircraft with aerostatic support of the relative thickness profile. The expediency of using thick sections D-2 of the Central Aero-Hydrodynamic Institute for the aircraft scheme "flying wing" with aerostatic support was shown.As the analysis of dependencies КΣ = f (α) and the relative thickness of the wing profile = 30%, the maximum aerodynamic efficiency КΣ мах corresponds to 12 units. The same value of Кмах wing without aerostatic support in the relative thickness of the wing profile amounts 20% (= 20%).

An Evolution of Hybrid Airship Vehicle (HAV) Envelope: Aerodynamics Analysis

HAV has a potential application as the new means to carry Ultra Heavy Payload cargo since it combines the buoyancy capabilities of Lighter-than-Air (LTA), and the aerodynamics of lifting body of Heavier-than-Air (HTA) for speed. Due to its potential, American Institute of Aeronautics and Astronautics (AIAA) has issued a Request for Proposal (RFP) regarding the Hybrid Airship Vehicle (HAV) as cargo transportation with several requirements. AIAA RFP required an envelope that can produce 60% of the lift from buoyancy and 40% of lift from aerodynamic. To satisfy the RFP requirements, this paper analyzed 4 different designs using Computational Fluid Dynamic (CFD) software. Design 4 was chosen as the final design because it meets all the requirements. It was found that at 5° Angle of Attack (AOA), the envelope produce highest aerodynamic lift over drag (L/D) ratio of 3.79. At higher AOA, flow separation occurs at the envelope tail section jeopardizing the aerodynamic characteristic of Design 4 envelope. The lift and drag force graphs were plotted at this AOA and it was found that the HAV envelope is capable of performing the tasks in the RFP.

Comparison of Digital DATCOM and Wind Tunnel Data of a Winged Hybrid Airship’s Generic Model

Use of low fidelity tools in designing subscale generic wind tunnel models is usually required to get first-hand knowledge about general trends of aerodynamic and stability parameters. Most of such tools are limited to well-defined conventional aircraft configurations. In the present work, aerodynamic and stability characteristics of a winged hybrid airship is explored at low subsonic speed by using Aircraft Digital DATCOM, which is based on semi-empirical methods for preliminary aircraft geometries. Spheroidal ellipsoidal shaped hull of the airship is modeled in DATCOM along with the geometrical details of wing and empennages. The prediction of zero lift drag coefficient, coefficient of lift and pitching moment is the focus of this paper. Except the drag coefficients, trends of analytical results compare well with experimental data.

Optimum Buoyant and Aerodynamic Lift for a Lifting-Body Hybrid Airship

The central problem of a hybrid airship design, the optimum apportionment of the total lift between the static buoyant lift and the aerodynamic lift, is studied. The lift apportionment is carried out for specific lifting-body shape represented by a and . Different flight strategies have been analyzed. Optimal configurations have been obtained for various flight-time constraints and cruise altitudes. The result of the study is a set of hybrid airships with optimal apportionment of total lift along with optimal flight profile. The set has been presented in the form of a design chart, and an optimal hybrid airship can be obtained, corresponding to a maximum flight time and a cruise altitude.

S1920104 係留型ハイブリッド飛行船システムの基礎的検討([S192-01]宇宙システムに関する実践的解決と知見の汎用化(1),宇宙工学部門)

Recently, it is possible to moor a balloon and airship at high altitude because of the development of high-specific strength material. The mooring hybrid airship will become a multi-purpose platform such as the local communication infrastructure in emergency and remote sensing. It is also expected to use as a new space launch platform as known rockoon. The recent hybrid airship has an advantage of not only using the force of buoyancy but also the aerodynamic lifting force. The attitude stability is expected be more than the conventional balloon system. The feasibility and application of the mooring of the hybrid airship is investigated in this study.

Cost Analysis of a Hybrid Airship Vehicle for Cargo Delivery

Cargo transportation is a very serious business and cost of delivering a pound of cargo for a mile keeps rising every day. Today, there are two options exist; fast but expensive aircraft and slow but inexpensive sea freight. A Hybrid Air Vehicle (HAV) was designed to solve this problem by combining the aerodynamic lift advantages from a lifting body shape and the effectiveness of lighter than air from buoyancy. These combined lifting capabilities gave the HAV enough lifting force to carry additional cargo compared to aircraft and its propeller engine gave it the ability to travel relatively fast compared to sea freight. The cost of transporting a pound of cargo a mile using proposed HAV is $ 0.00022/lb-mile as compared to $0.00043/lb-mile for C-5 Galaxy which translates to nearly 48% saving. The HAV cost 1000% more than sea freight but it is 647% faster.

Cost analysis of stratospheric albedo modification delivery systems

We perform engineering cost analyses of systems capable of delivering 1–5 million metric tonnes (Mt) of albedo modification material to altitudes of 18–30 km. The goal is to compare a range of delivery systems evaluated on a consistent cost basis. Cost estimates are developed with statistical cost estimating relationships based on historical costs of aerospace development programs and operations concepts using labor rates appropriate to the operations. We evaluate existing aircraft cost of acquisition and operations, perform in-depth new aircraft and airship design studies and cost analyses, and survey rockets, guns, and suspended gas and slurry pipes, comparing their costs to those of aircraft and airships. Annual costs for delivery systems based on new aircraft designs are estimated to be $1–3B to deliver 1 Mt to 20–30 km or $2–8B to deliver 5 Mt to the same altitude range. Costs for hybrid airships may be competitive, but their large surface area complicates operations in high altitude wind shear, and development costs are more uncertain than those for airplanes. Pipes suspended by floating platforms provide low recurring costs to pump a liquid or gas to altitudes as high as ∼ 20 km, but the research, development, testing and evaluation costs of these systems are high and carry a large uncertainty; the pipe system’s high operating pressures and tensile strength requirements bring the feasibility of this system into question. The costs for rockets and guns are significantly higher than those for other systems. We conclude that (a) the basic technological capability to deliver material to the stratosphere at million tonne per year rates exists today, (b) based on prior literature, a few million tonnes per year would be sufficient to alter radiative forcing by an amount roughly equivalent to the growth of anticipated greenhouse gas forcing over the next half century, and that (c) several different methods could possibly deliver this quantity for less than $8B per year. We do not address here the science of aerosols in the stratosphere, nor issues of risk, effectiveness or governance that will add to the costs of solar geoengineering.

Design of a new tandem wings hybrid airship

It is scientifically important science value and engineering promising to develop the buoyancy-lift integrated hybrid airship for high attitude platform. Through the numerical method, a new tandem wings hybrid airship with both higher utility value and economy efficiency was obtained and its total performance and technical parameters were analyzed in detail. In order to further improve the lift-drag characteristics, we implemented the optimization design for aerodynamic configuration of tandem wings hybrid airship via the response surface method. The results indicate that the tandem wings hybrid airship has considerable volume efficiency and higher aerodynamic characteristics. After optimization, the lift-drag ratio of this hybrid airship was increased by 6.08%. In a given gross lift condition, tandem wings hybrid airship may provide more payload and specific productivity. Furthermore, the size of tandem airship is smaller so the demand for skin flexible materials can be reduced. Results of this study could serve as a new approach to designing buoyancy-lifting integrated hybrid airship. hybrid airship, tandem wings, numerical simulation, aerodynamic configuration, optimization design

Ceramic engine considerations for future aerospace propulsion

PurposeThe purpose of this paper is to outline the potential usage of ceramic engines in combination with other technologies as a possible propulsion contender for future aerospace applications.Design/methodology/approachThe possibility of enabling novel propulsion systems in aerospace engineering is examined through a multilateral review study concerning ceramic engines and a proposed design approach. In view of the benefits and challenges of employing ceramic engines as possible candidates for the sustainable solutions of the future, a fundamental design proposal is presented for a conceptual generic unmanned air vehicle (GUAV).FindingsThe findings of this article identify a number of useful scenarios for future ceramic engine applications and considerations.Research limitations/implicationsIt is imperative to emphasize that this conceptual article solely sheds light on a limited number of key ideas associated with ceramic engines and their possible applications. Thus, many new areas may emerge and impact the application of ceramic engines in light of more in‐depth conceptual studies.Practical implicationsImplications of ceramic engine utilization in aeronautical applications may result in enhanced performance characteristics and less operational costs. Further implications could possibly be extended to various naval/automotive applications and new configurations of transportation vehicles.Social implicationsThe paper aims to generate an interest amongst younger individuals and environmental aware enthusiasts to consider ceramic engines for transportation applications to a greater extent than before.Originality/valueThe implementation of this particular conceptual design results in a synergistic ceramic engine combination with a hybrid airship design in novel aeronautical applications.

Investigation of Aerodynamic Parameters of a Hybrid Airship

The aerodynamic parameters of a preliminary winged-hull airship design are investigated. The research methodology involved the use of numerical simulation and wind tunnel testing. The aerodynamic parameters of the design are first computed using a commercial CFD code. The force and moment coefficients are then measured on a scaled model in the IIUM low speed wind tunnel. The experimental results generally agree with the CFD predicted data. Addition of a wing to conventional airship increases the lift substantially with a reasonable increase in drag. The longitudinal and directional stabilities were found to be statically stable, however, both the conventional airship and the hybrid airship were found to have poor rolling stability. CFD simulations show that modifications to the wing placement and its dihedral have strong positive effect on the rolling stability.