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Airframe section of rockets, missiles and launch vehicles are typically cylindrical in shape. The cylindrical shell is subjected to high axial load and an external pressure during its operation. The design of cylinders subjected to such loads is generally found to be critical in buckling. To minimize the weight of cylinders, it is typically stiffened with rings and stringers on the inner diameter to increase the buckling load factor. Conventionally the buckling load estimated by analytical or numerical means is multiplied by an empirical factor generally called Knockdown factor (kdf) to get the critical buckling load. This factor is considered to account for the variation between theory and experiment and is specified by handbooks or codes. In aerospace industry, NASA SP 8007 is commonly followed and it specifies the kdf as a lower bound fit curve for experimental data .

The study of aerodynamic forces in hypersonic environments is important to ensure the safety and proper functioning of aerospace vehicles. These forces vary with the angle of attack (AOA) and there exists an optimum angle of attack where the ratio of the lift to drag force is maximum. 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. The commercial CFD solver ANSYS FLUENT is used for the computational analysis and the mesh is generated using the ICEM CFD module of ANSYS. Air is selected as the working fluid. The simulation is carried out for a time duration of 1.2 ms where it reaches a steady state and the lift and drag forces and coefficients are estimated. The pressure, temperature, and velocity contours at different angles of attack are also observed.

This specification covers fuel-resistant polysulfide (T) sealing compounds supplied as a two-component system.

This SAE Aerospace Standard (AS) defines minimum performance standards (MPS) for fuel flowmeters, fuel flow indicators, and fuel flow transmitters. The fuel flow indicators and transmitters are intended for use in 14 CFR Part 23, 25, 27, and 29 aircraft equipped with reciprocating and turbine engines. Multiple function displays are not within the scope of this SAE Aerospace Standard (refer to AS6296).

This SAE Aerospace Standard (AS) provides the general performance, design, installation, test, development, and quality assurance requirements for the flight control related functions of the Vehicle Management Systems (VMS) of military piloted aircraft. It also provides specification guidance for the flight control interfaces with other systems and subsystems of the aircraft.

The SAE AE-5CH Taskgroup has determined that high flow liquid hydrogen fueling couplings need to be developed in order to fast fill aircraft at the airport. Though the flow rates from a current liquid hydrogen bayonet connect may reach the lower bound flow rates of regional aircraft, there are some shortcomings to this connector for aerospace. For this reason a new specification for flow rates for regional to narrowbody (and potentially later widebody) are to be developed in this documenet. Harmonization for lower flow rates (such as up to 20kg/minute) are planned to be harmonized with ground vehicle fueling such as with ISO 13984. Within this document,coupling descriptions including Flow rates from 84 to 200 kg/minute will be evaluated (and potentially higher), and requirements and testing and safety targets will be specified.

In order to study the tire friction characteristics under wet skid surface, the “pseudo” hydrodynamic pressure bearing effect is used to be equivalent to the hydrodynamics of water film, and an advanced Lugre tire hydroplaning dynamic model is developed by combining the arbitrary pressure distribution function. The water hydroplaning dynamic tests were carried out for 285/70R19.5 tire under wet of different water film thickness and dry conditions, and the parameters of the advanced Lugre tire dynamic model were identified. The results show that the tire water-skiing model proposed in this paper can effectively simulate the friction characteristics of tires under different water film thicknesses. Under dry conditions, 0.5mm water film and 1mm water film road conditions, the relative errors of the maximum tire friction coefficient between the tested and advanced Lugre tire model are 1.11%, 0.12% and 0.16%, respectively.

The problem of keeping the stable starting performance of diesel engine under high altitude and low temperature conditions has been done a lot of research in the field of diesel engine, but there is a lack of research on extreme conditions such as above 2000 meters above sea level and below 0°C. Aiming at solving the cold start problem of diesel engine in extreme environment, a set of chamber system of cold start environment diesel engine was constructed to simulate environment of 3000m altitude and -20°C. A series of experimental research was conducted on cold start efficiency optimization strategy of a certain type of diesel engine at 3000m altitude and -20°C. In parallel, a diesel engine model was constructed through Chemkin to explore the influence of the three parameters of compression ratio, stroke length, and fuel injection advance angle on the first cold start cycle of diesel engine at 4000m altitude and -20°C.

This specification covers a premium aircraft-quality, corrosion-resistant steel in the form of bars, wire, forgings, and forging stock.

This SAE Aerospace Recommended Practice (ARP) provides the technical terms and nomenclature, together with their definitions and abbreviations/acronyms that are used in aerospace fluid power, actuation and control systems. NOTE: ARP490 and ARP4493 are sources for definitions specifically for electrohydraulic servovalves.

Airborne compression-ignition engine operations differ significantly from those in ground vehicles, both in mission requirements and in operating conditions. Unique challenges exist in the aviation space, and electrification technologies originally developed for ground applications may be leveraged to address these considerations. One such technology, electrically assisted turbochargers (EATs), have the potential to address the following: increase the maximum system power output, directly control intake manifold air pressure, and reignite the engine at altitude conditions in the event of an engine flame-out. Sea-level experiments were carried out on a two-liter, four-cylinder compression-ignition engine with a commercial-off-the-shelf EAT that replaced the original turbocharger. The objective of these experiments was to demonstrate the technology, assess the performance, and evaluate control methods at sea level prior to altitude experimentation.