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The global electric and hybrid aircraft market utilizing lithium-ion Energy Storage Systems (ESS) as a means of propulsion, is experiencing a period of extraordinary growth. We are witnessing the development of some of the most cutting-edge technology, and with that, some of the most complex challenges that we as an industry have ever faced. The primary challenge, and the most critical cause of concern, is a phenomenon known as a “Thermal Runaway”, in which the lithium-ion cell enters an uncontrollable, self-heating state, that if not contained, can propagate into a catastrophic fire in the aircraft. A Thermal Runaway (TR) can be caused by internal defects, damage, and/or abuse caused by an exceedance of its operational specifications, and it is a chemical reaction that cannot be stopped once the cell has reached its trigger temperature.

In recent years, the increasing complexity of modern aerospace systems has driven the rapid adoption of robust Model-Based Systems Engineering (MBSE). MBSE is a development methodology centered around computational models, which are instrumental in supporting the design and analysis of intricate systems. In this context, the Architecture Analysis and Design Language (AADL) and Systems Modeling Language (SysML) are two prominent modeling languages for specifying and analyzing the structure and behavior of a cyber-physical system. Both languages have their own specific use cases and tool environments and are typically employed to model different aspects of system design. Although multiple software tools are available for transforming models from one language to another, their effectiveness is limited by fundamental differences in the semantics of each language.

As model-based systems engineering is proliferating throughout the aerospace industry as a method to manage the development of complex cyber-physical systems, opportunities to leverage formal methods for verification and validation purposes are significant. As a system model described in SysML can contain the level of semantics required to define strict system requirements, it is possible to create a translation tool to generate SRL (SADL (Semantic Application Design Language) Requirements Language) to leverage ASSERT™ (Analysis of Semantic Specifications and Efficient generation of requirements-based Tests) for verification and validation of the system requirements. SADL [13] is a controlled English grammar that translates directly into OWL (Web Ontology Language) [14]. As part of the validation of the SRL requirements, ASSERT™ leverages a theorem prover to look for conflict and completeness errors.

Geometry simplification is a critical step of performing conjugate heat transfer analysis utilizing computational fluid dynamics (CFD). This paper provides a standard methodology to simplify the geometry of electric rotating machines such as electrical generators and electrical motors (both air and liquid cooled). These machines are extremely complex in design and CFD plays an imperative role in their optimization. These machines are extensively deployed throughout aerospace and automotive industries where optimization of weight, volume, and performance is paramount especially given the current global transition to renewable energy sources and vehicle hybridization / electrification.

Protecting against atmospheric icing conditions is critical for the safety of aircraft during flight. Sensors and probes are often used to indicate the presence of icing conditions, enabling the aircraft to engage their ice protection systems and exit the icing cloud. Supercooled large drop icing conditions, which are defined in Appendix O of 14 CFR Part 25, pose additional aircraft certification challenges and requirements as compared to conventional icing conditions, which are defined in Appendix C of 14 CFR Part 25. For this reason, developing sensors that can not only indicate the presence of ice, but can also differentiate between Appendix O and Appendix C icing conditions, is of particular interest to the aviation industry and to federal agencies. Developing detectors capable of meeting this challenge is the focus of SENS4ICE, a European Union sponsored project.

Since the early days of aviation, when an AC-type generator became a primary source of electrical power for all aircraft systems, the demand for electrical power has steadily grown. Following rapid technology and scientific advancements in the aerospace industry, the complexity and criticality of all aircraft systems have increased to the point where multiple independent and isolated electrical power sources are required. In such an environment, with two or more variable-frequency AC-type generators that can be simultaneously activated to provide electrical power to the aircraft power distribution system, a safe power transfer process becomes a major priority. This means that any two independent aircraft AC power sources with different frequencies or phase angles cannot be connected simultaneously to a common power bus.

This paper reports the development of an operation support system for production equipment using image processing with deep learning. Semi-automatic riveters are used to attach small parts to skin panels, and they involve manual positioning followed by automated drilling and fastening. The operator watches a monitor showing the processing area, and two types of failure may arise because of human error. First, the operator should locate the correct position on the skin panel by looking at markers painted thereon but may mistakenly cause the equipment to drill at an incorrect position. Second, the operator should prevent the equipment from fastening if they see chips around a hole after drilling but may overlook the chips; chips remaining around a drilled hole may cause the fastener to be inserted into the hole and fastened at an angle, which can result in the whole panel having to be scrapped.

The objective of this paper is to analyze a complete fuselage of an airplane made of composite materials. The analysis presented includes designing a 3D fuselage structure in which parameters are calculated using various stress and deformation scenarios. Static numerical results propose a composite fuselage structure to reduce stress and deformation levels by 45 and 33% compared to an equivalent (existing) aluminum fuselage. This work is to continue with specific characteristics of the composite and considerations to more realistic loading conditions (dynamism, impact, fatigue). A complete study should suggest converting flying vehicles to composites, to increase performances, minimize weights, and improve payloads.

This paper presents a study of numerical cold flow analysis of double-base swirl injector design using Ansys Fluent. The study focuses on the design validation and development of double-base liquid-liquid swirl injector for Ethanol(Fuel) and Hydrogen Peroxide(Oxidizer) based liquid propellant rocket engine. The green propellant contains 80% Ethanol (C2H5OH) as fuel and 60% Hydrogen Peroxide (H2O2) as oxidizer. A comprehensive data, obtained from NASA CEARun code, of performance parameters and carbon monoxide and carbon dioxide emission of most commonly used propellant is compared with ethanol and hydrogen-peroxide based propellant is presented for reference. Secondly, the paper presents the theoretical design model of Swirl Injector, and numerical cold flow study of swirl injector model. For this the 3D models of fuel and oxidizer swirl nozzles are designed separately as per the theoretical design parameters. Poly-hexacore type fluent meshing is used to generate valid mesh.

The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools.

Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD).

Aluminium composites are remarkably used in automotive, aerospace, and agricultural sectors because of their lightweight with definable mechanical properties. The stir casting route was followed to fabricate cylindrical samples with base aluminium alloy LM4, LM4/SiC, LM4/Al2O3, and LM4/SiC/Al2O3. The tensile strength, compressive strength, hardness, and micro-structural analysis were performed on samples and Finite element analysis (FEA) was adopted to predict the failure modes of composites. The composites experimental results were found to be in line with the FEA results, however, the LM4/SiC/Al2O3 revealed better results on the mechanical properties when compared with other composite configurations. The mechanical properties improvement like hardness 5%-11%, tensile strength 10.26%-20.67%, compressive strength 15.19% - 32.58% and 71.52 - 82.1% reduction in dimension have been achieved in LM4/SiC/Al2O3 composite comparing to base metal.

In radiography testing, the radioactive elements Iridium 192 (Ir192) and Cobalt 60 (Co60) are employed to detect subsurface and inner flaws. These radioactive components are kept secure within the radiation-protected source camera. Despite the fact that the camera is safe, there is a little quantity of radiation that may harm human body cells. In this present study, it restricts radiation emission by placing a lead sheet over the source camera, which absorbs the produced radiation. The innovative concept involves in this present work is to place a manually operated switch near the radiation source to emit radiation.

The prospective generation of Unmanned Aerial Vehicles (UAVs) can attempt to eliminate conventional primary control surfaces, thereby seeking to enhance operational efficiency. This endeavor constitutes an experimental manifestation of morphing principles utilizing Shape Memory Alloy (SMA), specifically Nitinol, to actuate control surfaces through a meticulously orchestrated application of power cycles at diverse frequencies. The integration of Morphing Technology has garnered heightened attention within the aviation industry, owing to its capacity to augment efficiency and performance across a spectrum of flight conditions. The intrinsic appeal of morphing lies in its potential to dynamically alter wing geometry during flight, thereby optimizing fuel efficiency and mitigating environmental impact through diminished carbon emissions resulting from reduced drag. This, in turn, necessitates reduced thrust to achieve similar or same performance levels.

A tandem aircraft configuration has two wings placed one behind the other longitudinally, with no dedicated horizontal stabilizer. Since there are two wings, high lift is obtained but also at the cost of additional structural weight and drag. In this article, a methodology is proposed to design a tandem aircraft configuration and depict the design process of the radio-controlled model. Flight test is conducted with the model to verify the stability and predicted performance. Aerodynamic optimization is conducted by using computational fluid dynamics to understand the effects of downwash from the front wing to the aft wing. In the end, a conventional aircraft is conceptually designed, which uses the same power plant configuration and the predicted performance is obtained. The predicted performance results of the tandem aircraft and the conventional aircraft are compared and the results are obtained.

The focus of this project is on the preliminary design of an unmanned aerial vehicle (UAV) utilizing a coaxial rotor setup, taking into account its flight dynamics. Additionally, a comprehensive aerodynamic analysis is conducted using computational fluid dynamics (CFD). The idealogy for our design came from the Rukma Vimana, a flying craft mentioned in the ancient Hindu Scriptures. The design is optimized with the coaxial copter setup, a different approach that has yet to be widely explored in the UAV aspect. Coaxial rotors are installed in pairs, with one rotor mounted above the other on concentric shafts. Both rotors have the same axis of rotation, but they rotate in opposite directions (contra-rotate). CFD simulations are conducted to see how the fluid medium flows over the unconventional design of the UAV. Three different in terms of three designs heights are considered, ie, a 30 cm height model, a 35 cm height model, and a 40 cm height model.

In a satellite thruster the function of injector plays a major role in controlling the combustion. This paper presents the numerical simulation of two most used injectors namely, impinging doublet, and triplet using Ansys fluent. The injectors are designed for the non-toxic, green propellants used in satellite thrusters. The present study focuses on the design and simulation of the injectors with 2 variant of green propellants i.e., Kerosene/Hydrogen-peroxide and Ethanol Amine/Hydrogen-peroxide. The objective of the study is to investigate the performance of the two injectors in terms of atomization, combustion efficiency and thrust generation. Theoretical design calculations were performed for a 20 N bi-propellant satellite thruster. A comparative study on the condensed combustion products and injector was carried out using NASA CEA Run code and Ansys fluent, respectively. The ethanol amine/hydrogen-peroxide injector showed better performance in terms of combustion efficiency.

Wire arc additive manufacturing technology has become a promising alternative technology to high-volume metal deposition in many manufacturing industries like aerospace and automotive due to arc stability, long process cycle time, and formability. In this work, the Fanuc arc mate robot forms a single-pass, single-layer structure with a 1.2 mm diameter wire of copper-coated steel. Pure Argon gas is used as a shielding gas to protect the weld from oxidation. Different welding speed is carried out to analyze the bead thickness and height. Current and voltage as a heat input with optimal welding speed, a 10 kg straight wall is built with an operative building rate of 3.94 kg/h. The Rockwell hardness test is used to determine the hardness of the material, and it is discovered that it is 80 HRB. The tensile test is performed to determine the tensile strength and yield strength of the component; the measured values are 483.88 N/mm2 and 342.156 N/mm2, respectively.

Efficient transportation for carrying heavy loads is a common challenge across various applications, from supermarkets to industrial purposes. Conventional trolleys often fall short when loaded with heavy cargo, resulting in increased exertion and diminished productivity. Moreover, these challenges can adversely affect posture and lumbar spine health, especially for elder people and persons with cervical problems. There is a need for more user-friendly, ergonomic, and space-efficient solutions. This project addresses these challenges through an innovative design that encompasses various aspects of trolley functionality, including the study of comfort, wheel selection, and material considerations, drawing from ergonomic research. Multiple methods are employed to optimize the trolley’s dimensions to improve its overall performance. The trolley’s design features a collapsible basket for the transport of smaller-sized items and a base frame for larger goods and luggage.

Employing the stir casting process, a unique hybrid composites were fabricated, using A356 as the matrix and reinforced with ZrSiO4 and TiB2 particulates. The produced specimens were initially in their as-cast state. Following that, the reinforcement particle concentrations were changed 2 and 4 weight percentages (wt%) of ZrSiO4 and keeping a constant 6 wt% of TiB2. Three samples were exposed to dry sliding conditions at room temperature using a tribometer. Two applied loads of magnitude 10N and 50N and a sliding velocity of 1m/s and 2m/s were selected as testing parameters. After measuring the wear rate (WR) and the coefficient of friction (COF), the worn-out pin surfaces were examined using scanning electron microscopy (SEM).