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The study's outcomes advance our understanding of the complex relationship between the radius of leading edges and hypersonic boundary layer stability and pave the way for tangible advancements in hypersonic vehicle design and operation, offering valuable contributions to developing safer and more efficient hypersonic vehicles. ...This research employs a comprehensive methodology to explore hypersonic boundary layers' stability and transition dynamics, focusing specifically on the influence of sharp and blunt leading edges. ...The Linear Stability Solver analysis constitutes a crucial phase wherein the research delves into the eigenvalue spectra, identifying dominant modes and closely scrutinizing the role of the modes in the transition process within the hypersonic boundary layers. This investigation into stability characteristics is paramount for designing and optimizing hypersonic vehicles, providing valuable insights to enhance their efficiency and performance.

Scramjet-based hypersonic airbreathers are needed for next-generation defense and space applications. Two scramjet configurations, namely, rectangular and axisymmetric, are primarily studied in the literature.

Severe problem of aerodynamic heating and drag force are inherent with any hypersonic space vehicle like space shuttle, missiles etc. For proper design of vehicle, the drag force measurement become very crucial.

The study of aerodynamic forces in hypersonic environments is important to ensure the safety and proper functioning of aerospace vehicles. ...In this paper, computational analysis has been performed on a blunt cone model to study the aerodynamic characteristics when hypersonic flow is allowed to pass through the model. The flow has a Mach number of 8.44 and the angle of attack is varied from 0º to 20º. ...This study helps in understanding the aerodynamic and stability characteristics of hypersonic vehicles at various angles of attack that is significantly different from those of the subsonic or supersonic vehicles.

This can be referred in future studies into the hypersonic regime and shape optimization to get the best suited geometry with high aerodynamic performance for a given free stream condition.

The urgent need to combat global warming has spurred legislative efforts within the transport sector to transition away from fossil fuels. Hydrogen is increasingly being utilised as a green energy vector, which can aid the decarbonisation of transport, including internal combustion engines. Computational fluid dynamics (CFD) is widely used as a tool to study and optimise combustion systems especially in combination with new fuels like hydrogen. Since the behaviour of the injection event significantly impacts combustion and emissions formation especially in direct injection applications, the accurate modelling of H2 injection is imperative for effective design of hydrogen combustion systems. This work aims to evaluate unsteady Reynolds-Averaged Navier Stokes (URANS) modelling of the advective transport process and related numerical methods.

In this work, an investigation of the enthalpy effects on the thermochemical non-equilibrium in hypersonic nozzles is performed. Three different nozzles, with different geometries and stagnation enthalpy conditions are used in this study.

Abstract The air-breathing hypersonic vehicle (AHV) holds the potential to revolutionize global travel, enabling rapid transportation to low-Earth orbit and even space within the next few decades.

Certified Machine Learning-Based Avionics: Unlocking Safer Revolutionizing Electronic Warfare: Unleashing the Power of High-Performance Software Defined Radios Deterministic and Modular Architecture for Embedded Vehicle Systems Approximating the Material Stresses and System Requirements for Hypersonic Flight Design Approaches for Established and Emerging RF Receiver Architectures Rydberg Technologies Shows Potential of Long-Range RF with Quantum Sensor at NetModX23 New Method to Measure Wind Speed Could Unlock Drones' Potential A fundamentally different approach to wind estimation using unmanned aircraft than the vast majority of existing methods.

Electrifying Aviation: The Path to Decarbonizing the Skies /Electric aviation mirrors the early stages of the electric vehicle revolution Advances in Military Avionics Technologies Create New Challenges for RF Test and Measurement Plasma Electrolytic Oxidation: The Future of Lightweight Designs in Aerospace and Defense Advanced RF Simulation Reduces Cost and Schedule Risk Assure 5G NTN Performance Before Launch In the complex and quickly evolving 5G NTN landscape, simulating, emulating, and evaluating RF systems boosts mission success. Qualification of Multi-Channel Direction Finding Radar Receivers in The Lab Bullet Impact Testing of Ammunition and Explosives at Picatinny Arsenal A bullet impact (BI) test for evaluating the response of energetically loaded items has been established at the U.S. Army Combat Capabilities Command (DEVCOM) Armaments Center (AC) Explosive Development Facility.

Abstract To assist in initializing the conceptual design of hypersonic aircraft, we outline a new, systematic framework based on historical aircraft data and primarily composed of design data and regression models. ...An example is provided to demonstrate the application of the framework to launch the conceptual design of a new hypersonic aircraft with a given set of mission requirements.

Abstract At hypersonic speed, severe aerodynamic heating is observed, and temperatures are too high to cool by radiation cooling; active cooling such as ablative cooling is helpful in this situation. ...A Computational Fluid Dynamics (CFD) simulation of a two-dimensional (2D) lifting body against thermally perfect air in a hypersonic region (Mach number, M > 5) is carried out for M = 5–9 to obtain a heat-transfer-minimized sweepback angle (ΛHT-min), at which heat transfer to the vehicle is minimum.

Abstract At supersonic aircraft speeds, aerodynamically heated surfaces, e.g., nose, wing leading edges, are infrared (IR) signature sources from the tactically crucial frontal aspect. This study numerically predicts and then illustrates the minimization of IR contrast between the nose and background sky radiance by the emissivity optimization (εw,opt) technique, which has the least performance penalties. The IR contrast between the aircraft nose and its replaced background in 1.9-2.9 μm short-wave IR (SW-IR), 3-5 μm medium-wave IR (MW-IR), and 8-12 μm long-wave IR (LW-IR) bands are obtained. The IR contrast especially in LW-IR (i) increases with flight Mach number (M ∞) for a given flight altitude (H) and εw (ii) decreases with increasing H for a given M ∞ and εw. The εw,opt for a flight altitude of 5 km is found to decrease from 0.99 at M ∞ = 0.001 (low subsonic) in all three bands to 2 × 10−4 in MW-IR and 0.0213 in LW-IR bands at M ∞ = 3 (high supersonic).

This Aerospace Information Report (AIR) addresses the subject of aircraft inlet-swirl distortion. A structured methodology for characterizing steady-state swirl distortion in terms of swirl descriptors and for correlating the swirl descriptors with loss in stability pressure ratio is presented. The methodology is to be considered in conjunction with other SAE inlet distortion methodologies. In particular, the combined effects of swirl and total-pressure distortion on stability margin are considered. However, dynamic swirl, i.e., time-variant swirl, is not considered. The implementation of the swirl assessment methodology is shown through both computational and experimental examples. Different types of swirl distortion encountered in various engine installations and operations are described, and case studies which highlight the impact of swirl on engine stability are provided. Supplemental material is included in the appendices.

This section presents the basic equations for computing ice protection requirements for nontransparent and transparent surfaces and for fog and frost protection of windshields. Simplified graphical presentations suitable for preliminary design and a description of various types of ice, fog, frost, and rain protection systems are also presented.

“An Assessment of Planar Waves” provides background on some of the history of planar waves, which are time-dependent variations of inlet recovery, as well as establishing a hierarchy for categorizing various types of planar waves. It further identifies approaches for establishing compression-component and engine sensitivities to planar waves, and methods for accounting for the destabilizing effects of planar waves. This document contains an extensive list and categorization (see Appendix A) of references to aid both the newcomer and the practitioner on this subject. The committee acknowledges that this document addresses only the impact of planar waves on compression-component stability and does not address the impact of planar waves on augmenter rumble, engine structural issues, and/or pilot discomfort.

Empowering Soldiers Through ISPDS Dispensable Gels vs Gap Filler Pads An Analysis of Thermal Management Materials Electronic Warfare Vying for Control of the Electromagnetic Spectrum More Bang for the Buck A New Design and Manufacturing Method for Deep Penetrating Bomb Cases A Comprehensive Way to Use Bonding to Improve RF Performance of Low Noise Amplifiers Army and Universities Deploy New Warfighter Communication Technology Radiation Effects on Electronics in Aligned Carbon Nanotube Technology (RadCNT) Characterizing the fundamental mechanisms and charge transport phenomena governing the interactions between ionizing and non-ionizing radiation with carbon-based (nanotube and graphene) field-effect transistors (FETs) devices and integrated circuits (ICs).

This SAE Aerospace Recommended Practice (ARP) provides guidance for substantiating the airworthiness of aircraft engine components. Generally these components are associated with the engine control system, the system or systems that allow the engine to provide thrust or power as demanded by the pilot of the aircraft while also ensuring the engine operates within acceptable operating limits. But these components may also include hardware and systems associated with engine lubrication, engine or aircraft hydraulic or electrical systems, aircraft environmental control systems, thrust reverser control, or similar aircraft or engine propulsion system functions. This paper develops the concept of using a 26 item matrix of environmental conditions for evaluating aircraft engine component airworthiness. This approach is compatible with current practices used in the industry and has been accepted by engine certification authorities as part of engine certification programs.

Focused on design For Missouri S&T Racing, knowing why a system was designed in a particular way is as important as knowing how it was designed. Taking the classroom to the racetrack Purdue University's Formula SAE team makes good racecars, even better engineers. Sticking to the schedule By strictly meeting deadlines, West Virginia University Institute of Technology team hopes to reach new heights in SAE Aero Design.