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Advancement in modern aircraft with the development of more dynamic and efficient technologies has led to these technologies increasingly operated near or at their operation limits. More comprehensive analysis methods based on high-fidelity models co-simulated in an integrated environment are needed to support the full utilization of these advanced technologies. Furthermore, the additional information provided by these new analyses needs to be correlated with updates to traditional metrics and specifications. One such case is the thermal limit requirement that sets the upper bound on a thermal system temperature. Traditionally, this bound is defined based on steady-state conditions. However, advanced thermal management systems experience dynamic events where the temperature is not static and may violate steady-state requirements for brief periods of time.

Vertical takeoff and landing vehicle platforms with many small rotors are gaining importance for small UAVs as well as distributed electric propulsion for larger vehicles. To predict vehicle performance, it must be possible to gauge interaction effects. These rotors operate in the less-known regime of low Reynolds number, with different blade geometry. As a first step, two identical commercial UAV rotors from a flight test program are studied in isolation, experimentally and computationally. Load measurements were performed in Georgia Tech’s 2.13 m × 2.74 m wind tunnel. Simulations were done using the RotCFD solver which uses a Navier-Stokes wake computation along with rotor-disc loads calculation using low-Reynolds number blade section data. It is found that in hover, small rotors available in the market vary noticeably in performance at low rotor speeds, the data converging at higher RPM and Reynolds number.

In a disc brake, when brake disc undergoes a brake cycle lot of heat is generated. The heat generated due to friction has to be dissipated by one or the other modes of heat transfer. Out of the three modes of heat transfer, convection is to be maximized as others may cause deterioration of neighboring parts. The disc is of ventilated type and hence the turbulence and mass flow rate through this ventilated area is to be optimized so as to improve the convective heat transfer coefficient. In this paper, a numerical investigation of a brake disc is done for studying its aero-thermal behavior and finding alternatives that perform better. An in-depth study of various design changes, previously done for improving heat transfer coefficient in ventilated disc, is done and these changes are incorporated in the existing design.

The widespread adoption of boosted, downsized SI engines has brought pre-ignition phenomena into greater focus, as the knock events resulting from pre-ignitions can cause significant hardware damage. Much attention has been given to understanding the causes of pre-ignition and identify lubricant or fuel properties and engine design and calibration considerations that impact its frequency. This helps to shift the pre-ignition limit to higher specific loads and allow further downsizing but does not fundamentally eliminate the problem. Real-time detection and mitigation of pre-ignition would thus be desirable to allow safe engine operation in pre-ignition-prone conditions. This study focuses on advancing the time of detection of pre-ignition in an engine cycle where it occurs.

A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

A novel aviation infrastructure system by a multilayer ecological & energized module (EEM) system is aiming to create a high safety & security, graceful and comfortable air travel environment, high-quality air, zero energy, zero-water-consumption, and zero-carbon with a 100% greening rate, etc. It contains a modular EEM optical runway, totally-enclosed EEM ecological modules, and EEM ecological modules with thin-film or silicon solar cells on the top layer, etc. With the light processed and enhancing and optimizing crushed shadows & blown highlights and high contrast color layout, the EEM optical runway has a powerful visual flight, runway visual range (RVR), and significant blown highlights in 3D position and posture in various complex weather and occasions for the instrument landing, manually land and taxiing, etc. It’s always clean and bright without lampblack and exhaust traces since it is easy to rinse and replace.

Begun in 2016, the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) was developed and agreed by International Civil Aviation Organization (ICAO) 191 Member States, while the Airport Carbon Accreditation was developed by the Airports, Council International Europe as a carbon management system and certification. The aviation industry has its own offsetting scheme to measure aviation emissions and carbon offsetting and it has become the first industry sector which leads the world making commitments to reduce emissions. CORSIA and the Airport Carbon Accreditation are programs that impose carbon management obligations on the aviation industry.

A well implemented and suitable training plan makes a company's operations more effective. In the aviation industry, qualified maintenance technicians are one of the most significant assets to improve safety of passengers and reliability of air transportation. This paper investigated the effectiveness of virtual simulation-based training in the aviation maintenance. It garnered data from a panel of experts to discover if virtual simulation-based training can be used instead of the traditional training techniques to train maintenance technicians. From the aviation industry in Saudi Arabia, 11 experts were selected and interviewed. Experts were asked 9 questions seeking their opinions on utilizing the virtual reality technology on the aviation maintenance training, and if it can overcome the limitations of utilizing traditional methods while providing the needed skills.

For new aircraft production, initial production typically reveals difficulty in achieving some assembly level tolerances which in turn lead to non-conformances at integration. With initial design, tooling, build plans, automation, and contracts with suppliers and partners being complete, the need arises to resolve these integration issues quickly and with minimum impact to production and cost targets. While root cause corrective action (RCCA) is a very well know process, this paper will examine some of the unique requirements and innovative solutions when addressing variation on large assemblies manufactured at various suppliers. Specifically, this paper will first review a completed airplane project (Project A) to improve fuselage circumferential and seat track joins and continue to the discussion on another application (Project B) on another aircraft type but having similar challenges.

Electrostatic Rotary Bell Sprayers (ERBSs) have been widely used in the painting industry, especially in the automotive and aerospace industries, due to their superior performance. The effects of the applied voltage and paint droplet charge values on the spraying pattern and coating Transfer Efficiency (TE) in the ERBS, including a high-voltage ring for spray cloud control, have been studied numerically in a wide range of droplet size distribution. A 3D Eulerian-Lagrangian numerical analysis is implemented under the framework of the OpenFOAM package. The fluid dynamics of turbulence, primary and secondary breakup procedures are modeled using a large eddy simulation (LES) model, Rosin-Rammler distribution, and modified TAB approach, respectively.

Day by day, airports adopt more IoT devices. However, airports are not exempt from possible failures due to malware’s proliferation that can abuse vulnerabilities. Computer criminals can access, corrupt, and extract information from individuals or companies. This paper explains the development of a propagation model, which started with a Delphi process. We discuss the preliminary implications for airports of the simulation model built from the Delphi recommendations.

Analytical calculations along with computational fluid dynamic (CFD) simulation of a Boeing 737-600 cabin with a single infector (a passenger) has been performed using a passive scalar gas with particle sizes similar to the sizes of influenza virus laden particles which are assumed to be comparable to the sizes of the Coronavirus laden particles. CFD results of the virus transport and concentration were used in conjunction with the Wells-Riley (WR) quanta estimation from two well-documented cases of influenza infection on airplanes (with the assumption that the infections were primarily from the airborne route), to estimate the infectious rate. The risk of infection is estimated by the quanta of viruses inhaled assuming 0.3 CFM of passive scalar gas corresponds to 1267 viruses/minute released. Results indicate that with a 3-hour flight, the risk of infection is nearly 50% for those sitting in the vicinity of the infector which is equal to 2-3 infections for 131 passengers.

The aerospace ecosystem is a complex system of systems comprising of many stakeholders in exchanging technical, design, development, certification, operational, and maintenance data across the different lifecycle stages of an aircraft from concept, engineering, manufacturing, operations, and maintenance to its disposal. Many standards have been developed to standardize and improve the effectiveness, efficiency, and security of the data transfer processes in the aerospace ecosystem. There are still challenges in data transfer due to the lack of standards in certain areas and lack of awareness and implementation of some standards. G-31 standards committee of SAE International has conducted a study on the available digital data standards in aircraft asset life cycle to understand the current and future landscapes of the needed digital data standards and identify gaps. This technical paper presents the study conducted by the G-31 technical committee.

The aircraft jet engine is one of the most complex multivariable systems with multiple inputs and multiple outputs. To attempt to optimize control functions or to address diagnostic problems, a detailed knowledge of all jet engine design parameters and performances is required. Although jet engines have been around for almost a century, there are only a few companies in the world presently designing and manufacturing them; as such these companies possess detailed knowledge of all relevant design characteristics and performance parameters. In the event where jet engine technical details are unknown, or only a few of them are known from manufacturer’s catalogues, the challenge becomes how to calculate and extrapolate critical performance parameters based on only fuel flow, jet exhaust temperature and total thrust.

Cooperative Maneuver Coordination (CMC) is one of the cornerstone technologies on the way to automated and connected driving of the future. The goal of this technology is to increase traffic safety and efficiency, by solving potential conflict situations on the road, based on cooperative maneuver planning, negotiation and decision-making, with the aid of inter-vehicular communication. This innovative topic represents a wide area for research projects, e.g., such as German funded project IMAGinE. A variety of different approaches for CMC has already been implemented and evaluated in the related work of the recent past. However, due to the high system complexity in general and vast testing effort in particular of these solutions, their actual impact on the traffic quality has not yet been extensively addressed, and therefore must be further investigated.

The current work investigates the hot corrosion demeanour of Hastelloy X weldment produced with autogenous mode through key-hole plasma arc welding (K-PAW). The hot corrosion test has been performed for weldment in molten salt-1 (MS-1) (75 % Na2SO4 + 25 % V2O5) and molten salt-2 (MS-2) (75 % Na2SO4 + 20 % V2O5 + 5 % NaCl) circumstance for 25 hrs (25 cycles) at 900 °C. The MS-1 substrate of both base metal and weldment provided the lowest weight gain than the MS-2 substrate. The NaCl in the MS-2 causes severe hot corrosion on the substrate, whereas the absence of NaCl in MS-1 reduces the hot corrosion effects. The highest parabolic constant is observed for K-PAW weldment in MS-2 condition. The tendency of hot corrosion rate follows the order of, Base Metal MS-1 < K-PAW MS-1 < Base Metal MS-2 < K-PAW MS-2. The occurrence of protective phases like chromium oxides (Cr2O3), spinel oxides (NiCr2O4 and NiFe2O4) Nickel oxide (NiO) on the substrate resist the further oxidation.

In the automotive applications, the main functionality of the HVAC system includes heating, ventilation, and cooling or air-conditioning of the vehicle to achieve the desired indoor thermal comfort. In the current scenario, the conventional vapor compression based HVAC system is widely used. The typical refrigerants used to operate this equipment include HFCs and HFOs which are susceptible to cause an environmental hazard. This article aims to assess the performance of a hypothetical solar-driven thermoelectric based rotary desiccant wheel HVAC system (D-HVAC) to be used for automotive applications. The D-HVAC system uses the desiccant wheel to remove the latent heat, energy wheel to remove the sensible heat, evaporating coolers to achieve further cooling, the regeneration of the desiccant wheel by hot air and water as the refrigerant. In the case of a solar-driven-DHVAC system, solar energy is utilized for the regeneration of the desiccant wheel in place of hot air.

Sealant is applied between joined aircraft parts in the final stage of the assembly, before installation of permanent fasteners. In this paper a novel approach for aircraft assembly simulation is suggested, which allows to resolve the transient interaction between parts and sealant in the course of airframe assembly process. The simulation incorporates such phenomena as compliance of parts, contact interaction between them and fluidity of sealant with presence of free surface. The approach based on fluid-structure interaction techniques consists of two basic steps: at the first one the pressure of sealant is found after corresponding fluid dynamics problem is solved and at the second the displacements of parts and sealant are calculated through the solving of contact problem. Iterations between structural and fluid dynamics solvers are performed to achieve convergence. The developed approach is demonstrated on example of joining of two test aircraft panels.

Riveting is an essential process for the pre-assembly as well as the final assembly of aircrafts. In many cases, the riveting process fails to be fully automated, for instance, in parts with complex geometries. Thus, manual riveting is still widely common. Several works have been carried towards semi-automatic riveting solutions, namely in riveting the section barrel of the aft section to its pressure bulkhead. In [1], a method of communication-free semi-automated riveting is proposed where a partially autonomous robot performs counter-holding while a human worker rivets. The method has been modeled and tested extensively in simulation. However, although a demonstration prototype has been developed, models have been tested on it curtly. This paper investigates experimental evaluation of different model variations on demonstration. The aim is to identify the boundaries of the method in real world conditions.

Aerospace engine parts are complex precision-engineered products with tighter assembly tolerances produced by conventional and non-conventional manufacturing processes. Variations in these manufacturing processes have to be controlled, process risks mitigated, and managed effectively, to facilitate the ease of aero-engine assembly to reduce overall variation and improve the assembly quality. One such technique is the application of the Selective Assembly as a Design for Manufacturing and Assembly (DfMA) tool. The paper details the methodology of Selective Assembly, its applications, benefits, and limitations in the aerospace industry along with a framework case study with a focus on ease of assembly and meeting the design intent of the assembly fit with the detailed study on the current traditional assembly process.