The geometry of high-pressure pump and injector nozzles crucially influences hydraulic behaviors (e.g., the start of injection, the pressure profiles developed in the high-pressure line, needle lift, and injection rates) in diesel engines. These factors, in turn, significantly impact fuel atomization, fuel–air mixing, combustion quality, and the formation of emissions. The main geometry parameters such as plunger diameter and the number and diameter of nozzles lead to the system complexity, requiring careful analysis, design, and calibration. In this study, a high-speed shadowgraph system and a high-resolution pressure recording system were developed to capture the start of injection, spray structure, and pressure profiles in the high-pressure line. Additionally, a model was developed using GT-Fuel package built within the GT-Suite of simulation tools to explore different plunger diameters and numbers and diameters of injector nozzles. These models were validated using the pressureNguyen, Quan Q., Vu, Manh D., Phung, Duoc V., Nguyen, Kien T., Vu*, Tuan N., Pham, Phuong X.
This specification covers a precipitation hardenable corrosion- and heat-resistant nickel alloy in the form of seamless tubingAMS F Corrosion and Heat Resistant Alloys Committee
This specification covers procedures for identifying carbon and low-alloy steels, corrosion- and heat-resistant steels and alloys, maraging and other highly alloyed steels, and iron alloy sheet, strip, and plate, and aircraft tubingAMS F Corrosion and Heat Resistant Alloys Committee
This SAE Standard describes the methods for testing flexible harness coverings for use on ground vehicle electrical distribution systems, specifically protection from severe mechanical impact. This SAE Standard shall apply to all tapes, extruded tubes, and textile sleeves used for this purposeHarness Covering Standards Committee
This specification covers a precipitation hardenable, corrosion- and heat-resistant nickel alloy in the form of seamless tubing 0.125 inch (3.18 mm) and over in nominal OD and 0.015 inch (0.38 mm) and over in nominal wall thicknessAMS F Corrosion and Heat Resistant Alloys Committee
The development of electric commercial vehicles brought up novel challenges in the design of efficient and reliable air brake systems. The compressor is one of the critical components of the air brake system and is responsible for supplying pressurized air to the brake system. In this study, we aimed to gather essential information regarding the pressure and flow rate requirements for the compressor in the air brake system of electric commercial vehicles. We extensively analyzed the existing air brake systems utilized in conventional commercial vehicles. We examined the performance characteristics of reciprocating compressors traditionally employed in these systems. Recognizing the need for novel compressor designs tailored to electric commercial vehicles, we focused on identifying the specifics such as efficiency, performance characteristics, reliability, and cost of the compressor. Our study utilized theoretical calculations to ascertain the optimal pressure and flow rate parametersDhere, Siddhant, Gupta, Suryakant, Kumar, G. C. Mohan, Reddy, Vamsikrishna
This specification covers a corrosion-resistant steel in the form of bars, wire, forgings, and forging stockAMS F Corrosion and Heat Resistant Alloys Committee
This specification establishes the requirements for flake or granular cetyl alcohol, solvents for dissolving the cetyl alcohol, preparation and application requirements for use of cetyl alcohol as an installation lubricant on mechanical fasteners, such as pins, bolts, nuts, washers, threaded or nonthreaded fastening devices, and inspection criteria for coated partsE-25 General Standards for Aerospace and Propulsion Systems
This article presents a strategy for the virtual calibration of a large-scale model representing a self-piercing rivet (SPR) connection. The connection is formed between a stack of three AA6016-T4 aluminum sheets and one SPR. The calibration process involves material characterization, a detailed riveting process simulation, virtual joint unit tests, and the final large-scale model calibration. The virtual tests were simulated by detailed solid element FE models of the joint unit. These detailed models were validated using experimental tests, namely peeling, single-lap joint, and cross-tests. The virtual parameter calibration was compared to the experimental calibration and finally applied to component test simulations. The article contains both experiments and numerical models to characterize the mechanical behavior of the SPR connection under large deformation and failureAndré, Victor, Costas, Miguel, Langseth, Magnus, Morin, David
This study aims to explore the wear characteristics of fused deposition modeling (FDM) printed automotive parts and techniques to improve wear performance. The surface roughness of the parts printed from this widely used additive manufacturing technology requires more attention to reduce surface roughness further and subsequently the mechanical strength of the printed geometries. The main aspect of this study is to examine the effect of process parameters and annealing on the surface roughness and the wear rate of FDM printed acrylonitrile butadiene styrene (ABS) parts to diminish the issue mentioned above. American Society for Testing and Materials (ASTM) G99 specified test specimens were fabricated for the investigations. The parameters considered in this study were nozzle temperature, infill density, printing velocity, and top/bottom pattern. The hybrid tool, i.e., GA–ANN (genetic algorithm–artificial neural network) has been opted to train, predict, and optimize the surfaceNarang, Rajan, Kaushik, Ashish, Dhingra, Ashwani Kumar, Chhabra, Deepak
This procurement specification covers the requirements for metal tube support clamps comprising of two spring clips made of corrosion and heat resistant steel and the associated PTFE single split cushion that supports the tube. See Figure 1G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
In the present work, a new methodology for predicting the performance of centrifugal compressors is developed. The proposed method differs from existing methods found in literature by gathering principal losses in three parameters: two constants and one variable, which is a function of the compressor wheel geometrical characteristics. As those parameters are constants for a given centrifugal compressor, there is no need for additional corrective parameters in order to obtain coherent results. Indeed, the proposed methodology does not depend on the choice of the slip factor correlation for the prediction of the correct pressure ratio. However, the choice of slip factor influences the efficiency computation. The prediction of the compressor maps for two full stage centrifugal compressors is presented and they show good agreement while compared with manufacturer’s data obtained from gas stand measurements. In addition, a method to obtain the surge line based on this methodology isMartinez Alvarado, Luis Enrique, Milosavljevic, Misa
This method outlines a standard procedure for performing conformity tests of bearings utilizing liners of bonded polytetrafluoroethylene (PTFE). The data from these tests shall be used to determine if the product meets the conformity requirements of the applicable specificationACBG Plain Bearing Committee
This procurement specification covers aircraft-quality solid rivets made from a corrosion resistant nickel-copper alloy of the type identified under the Unified Numbering System as UNS N04400 and of 46 ksi minimum shear strengthE-25 General Standards for Aerospace and Propulsion Systems
This procurement specification covers tubular, blind rivets fabricated from a corrosion resistant nickel-copper alloy of the type identified under the Unified Numbering System as UNS N04405, and of 52 ksi minimum shear strength for self-plugging style rivetsE-25 General Standards for Aerospace and Propulsion Systems
Understanding left-turn vehicle-pedestrian accident mechanisms is critical for developing accident-prevention systems. This study aims to clarify the features of driver behavior focusing on drivers’ gaze, vehicle speed, and time to collision (TTC) during left turns at intersections on left-hand traffic roads. Herein, experiments with a sedan and light-duty truck (< 7.5 tons GVW) are conducted under four conditions: no pedestrian dummy (No-P), near-side pedestrian dummy (Near-P), far-side pedestrian dummy (Far-P) and near-and-far side pedestrian dummies (NF-P). For NF-P, sedans have a significantly shorter gaze time for left-side mirrors compared with light-duty trucks. The light-duty truck’s average speed at the initial line to the intersection (L1) and pedestrian crossing line (L0) is significantly lower than the sedan’s under No-P, Near-P, and NF-P conditions, without any significant difference between any two conditions. The TTC for sedans is significantly shorter than that forMatsui, Yasuhiro, Narita, Masashi, Oikawa, Shoko
This specification covers a corrosion- and heat-resistant steel in the form of bars, wire, forgings, mechanical tubing up to 5.00 inches (127 mm), inclusive, in nominal diameter or least distance between parallel sides (thickness), and stock for forging or headingAMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stockAMS E Carbon and Low Alloy Steels Committee
This procurement specification covers retaining rings of the spiral wound type with uniform rectangular cross-section, made of a corrosion and heat resistant age hardenable iron base alloy of the type identified under the Unified Numbering System as UNS S66286, work strengthened and heat treated to a tensile strength of 185 to 240 ksi at room temperatureE-25 General Standards for Aerospace and Propulsion Systems