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Aviation industry is striving to leverage the technological advancements in connectivity, computation and data analytics. Scalable and robust connectivity enables futuristic applications like smart cabins, prognostic health management (PHM) and AI/ML based analytics for effective decision making leading to flight operational efficiency, optimized maintenance planning and aircraft downtime reduction. Wireless Sensor Networks (WSN) are gaining prominence on the aircraft for providing large scale connectivity solution that are essential for implementing various health monitoring applications like Structural Health Monitoring (SHM), Prognostic Health Management (PHM), etc. and control applications like smart lighting, smart seats, smart lavatory, etc. These applications help in improving passenger experience, flight operational efficiency, optimized maintenance planning and aircraft downtime reduction.

In this work, a newly developed iced-aircraft modeling tool is applied to wings, engine inlets, and helicopter rotors. The tool is based on a multiscale-physics, unstructured finite-volume CFD approach and is applicable to general purpose aircraft icing applications. The present approach combines an Eulerian-based droplet-trajectory solver that is loosely coupled, in a time-accurate manner, to a surface-film and ice-evolution model. The goal of the model is to improve the fidelity of ice accretion modeling on dynamic geometries and for three-dimensional ice shapes typical of helicopter rotors. The numerical formulation is discussed and presented alongside 2D and 3D static validation cases, and dynamic helicopter rotors. The present results display good validation for predicting ice shape on a variety of geometries, and a strong initial capability of modeling ice forming on helicopters in forward flight.

A series calculation methodology from the injector nozzle internal flow to the fuel spray was applied to investigate the internal flow and spray of a nozzle whose orifices distributed in different space layers. The nozzle internal flow calculation using an Eulerian three-fluid model and a cavitation model was performed. The needle valve movement during the injection period was taken into account in this calculation. The transient data of spatial distributions of velocity, turbulent kinetic energy, dissipation rate, void fraction rate, etc. at the nozzle exit were extracted. These output data were transferred to the spray calculation, in which a primary break-up model was applied to the Discrete Droplet Model (DDM). The calculation results were compared with the results of the measurement data of spray. Predicted spray morphology and penetration showed good agreement with the experiental data.

The aim of the study is to understand risks associated with a crew member accessing behind the closeout panel or space. Since there is a possibility that a particular closeout space is filled with a harmful gas mixture that is different from the cabin atmosphere, the time needed to ventilate this space should be evaluated. The three-dimensional Computational Fluid Dynamics (CFD) model developed for prediction of time-dependent turbulent flow and concentration fields inside and near a suddenly-opened box is described in the paper. Several cases with different positions of the closeout space, initially filled with pure oxygen, are analyzed under the U.S. Laboratory (USL) ventilation conditions. A simplified flow model, where a suddenly-opened box is ventilated by uniform external throughflow, is considered as well.

Within the frame of a series of initiatives aimed at improving effectiveness of its aircraft design and analysis capabilities, the Military Division of Daimler-Benz Aerospace (Dasa) is developing MIDAS, a multidisciplinary integration framework for a suite of numerical codes suitable to quickly and still accurately assess aircraft performance. As MIDAS specifically targets support of configurational studies in a Conceptual and Preliminary Design environment, peculiar requirements such as scope, range of applicability, and robustness of the system components, reliability of results, care-free operability, and fast response times have to be properly addressed.

This work presents the implementation and validation efforts of a 3D ice accretion solver for aeronautical applications, MESS3D, based on the advanced Messinger model. The solver is designed to deal with both liquid phase and ice crystal cloud conditions. In order to extend the Messinger model to 3D applications, an algorithm for the water run-back distribution on the surface was implemented, in place of an air flow stagnation line search algorithm, which is straightforward in 2D applications, but more complicated in 3D. The developed algorithm aims to distribute the run-back water in directions determined by air pressure gradients or shear forces. The data structure chosen for MESS3D allows high flexibility since it can manage the necessary input solutions on surface grids coming from both structured and unstructured solvers, regardless the number of edges per surface cells.

ANY aggregation of parts assembled to obtain a mechanical result is a series of compromises. The relative importance of the objectives governs the nature of the compromise. The major objectives to be considered in the design of airplane engines are (1) Reliability (2) Small weight per horsepower (3) Economy of fuel and oil consumption (4) Carburetion that permits of easy starting; maximum power through a range of 30 per cent of the speed range; and idling at one-quarter maximum speed without danger of stalling (5) Ability to deliver full power through a small speed range without excessive vibration (6) Complete local cylinder-cooling under conditions of high mean effective pressure (7) Compactness The automobile engine must have (1) Reliability (2) Silence (3) Carburetion that accomplishes proper and even firing in all cylinders under varying throttle conditions, through speeds covering more than 90 per cent of the speed range of the engine.

The characteristics of turbines for turbojet and space power plant applications are compared on the basis of power requirement trends, working fluids, materials, and system requirements. The differences in Brayton and Rankine cycles, the requirements of the cycles imposed on turbines, and typical losses inherent in present low power space turbines are discussed. A comparison is made of representative present and future turbines for turbojet and space power applications. Future large space turbines will parallel the performance and design techniques of high performance gas turbines. Some of the design techniques of steam turbines can also be used because of experience with wet vapor and long endurance. The future goals and problem areas of turbojet and space turbines are shown.

Cockpit Display System (CDS) suppliers need to now prepare for the cockpits of the future. The architecture, design and ergonomics of the cockpits have to be re-assessed in order to place the pilot at the center of the system, while taking into account the increasing complexity of the systems. Human Machine Interfaces (HMI) have to be simplified and made more intuitive. Thus, there is a need for dedicated HMI design tools and human-factor-oriented processes that are able to support both the required flexibility in the display creation for various types of interactive displays and the increasing demand for safety in avionics displays. This paper presents a COTS approach to these needs, which combines the SCADE Display model-based HMI software design solution, designed from the ground up for displays with safety objectives, with an associated prototyping and development process largely based upon human factors assessment.

An Increase in jet penetration due to the wall boundary layer is determined in the flow field including an aerodynamic interference between the wall boundary layer and the jet. The aerodynamic effect of the wall boundary layer is replaced by that of a secondary vortex filament resulting from vorticity in the wall boundary layer. A differential equation governing the increase in jet penetration is derived using the circulation around the secondary vortex filaments, its induced velocity and the empirical decay law of the jet axial velocity along the jet centerline. The circulation around the secondary vortex filament is estimated according to Hawthorne's theory (1)* and expressed in terms of aerodynamic characteristics of the wall boundary layer. A numerical example of the present analysis shows a fairly good agreement with the experiment. This indicates that the used vortex flow model simulates the real flow conditions well.

This paper describes some of the steps necessary to certificate a camera installation in a Part 23 aircraft. The camera is large and necessitates the severing of a major structural member (keel beam). Damage tolerance analysis is required because of the penetration of the pressure vessel. Cable rerouting is necessary because of the location of the hole. The design, the basis for the structural substantiation and the structural substantiation of this design are discussed in this paper.

The paper traces the development of the approach to airworthiness taken by Canadian government authorities from its origin through to current practices. It describes the Aerospace industry, the carriers and general aviation in statistical terms, indicates the impact of economic regulatory reform and suggests the way ahead for Canadian and other authorities lies in the attitude and methodologies practiced by the European authorities in their development of JARs. I SHOULD PERHAPS start this presentation with a short word about authorities. At the conclusion of a speech on safety regulation by Mr. Ronald Ashford of the UK Civil Aviation Authority, reported in Flight International of April 19, 1986, the following quotation from St. Paul to the Romans appeared: “You wish to have no fear of the authorities? Then continue to do right and you will have their approval, for they are God's agents working for your good”.

An electrical system composed of an integral main engine electrical starter/generator and a power management and distribution system for a high performance more electric airplane is presented. The paper emphasizes the fault tolerance and high reliability requirements and discusses the necessary architecture to satisfy them. A number of critical technical issues associated with the more electric airplane, such as severe EMI environment, regenerative power, and system integration and stability are discussed.