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2021 Cadillac Escalade unveil Joanne Leddy

Abstract This article aims to identify the best combination of intake port angle (IPA) and cylinder head pentroof angle (PA) of a gasoline direct injection (GDI) engine to achieve a simultaneous reduction in the fuel consumption and the exhaust emissions using computational fluid dynamics (CFD) and optimization techniques. The present study is carried out on a single-cylinder, four-stroke GDI engine. The design space is bound by the range of the IPA (35°, 80°) and the PA (5°, 20°). The initial data set consists of 80 design points, which are generated using the uniform Latin hypercube (ULH) algorithm. CFD simulations were carried out at all the points in the initial data set using CONVERGE at engine speed of 2,000 rev/min and the overall equivalence ratio of 0.7 ± 0.05.

Abstract This article investigates an adaptive test design approach for the purpose of a model-based engine calibration. Two different new algorithms are presented to take engine boundaries during test execution into account and selectively calculate new test points to increase engine model quality and its input domain. The algorithms are implemented into an adaptive test design framework and evaluated by an engine simulation with artificial Brownian noise added. The results highlight an increase in input space evaluation volume and a decrease in engine model error, while meeting calculation time constraints.

Abstract An effective damper is among the most important components of the suspension system. It ensures the right amount of damping force is acting on the suspension system to provide comfort to the passengers and proper road holding to tires. Unfortunately, the energy absorbed by the dampers from the suspension system gets wasted in the form of heat. In this article, it is proposed to use innovative electromagnetic damper (EMD) with a crank-lever mechanism to recover energy from the suspension system. The goal is to develop a lightweight design of EMD that can recover a high amount of power. For the design, an off-road vehicle is used since in off-road vehicles the amount of power wasted in the suspension system is high. Three different design approaches are used, which include single-stage gearbox type, two-stage gearbox type, and three-stage gearbox type of CLEMD.

Abstract In this article, an active sound generation (ASG) system is proposed to simulate engine order sound that is typically found in vehicles equipped with internal combustion engines. Based on an A-class electric SUV, a mathematical model simulating engine order sound is established, and a short-time Fourier transform and synthesis technique is implemented. An ASG hardware along with its main functional circuits is designed, and the control software is developed. The ASG system is configured based on the loudspeakers used by the vehicle’s audio system and the frequency response characteristics of the loudspeakers is obtained by testing. An interior sound design method simulating acceleration conditions is investigated in detail. The control method is formulated based on the interior noise characteristics in accordance with the engine order sound amplitude variation.

Abstract This article presents a robustness analysis study for the model reference controller (“MRC”) of active suspension system. The MRC employs both suspension look-ahead preview and wheelbase preview concepts. The methodology of the MRC is based on the ideal hybrid skyhook-groundhook scheme. A 13 degree of freedom full vehicle model is developed and validated. The engine mass, driver seat, and anti-roll bar are considered in the model. The MRC strategy uses eight proportional-integral-derivative (PID) controllers for both body and wheel control. A gradient based on optimization algorithm is applied to obtain the controller parameters using a cost function including both ride comfort and road holding performance. The robustness analysis of the controller is performed by evaluating the MRC controller performance under different driving conditions, including different road profiles, different vehicle speeds, and different vehicle loading.

Carburetor icing (CI) was the most commonly cited factors in general aviation accident category with 1,019 (34%) accidents. The objective of the study is to measure the CI tendency of selected fuels by the application of factor analysis (FA). All the test fuels were characterized based on chemical and physical properties of the fuels. Gas chromatographic (GC) analysis of the tested fuels were categorized based on hydrocarbon types and basic fuel properties. The study considered sixteen variables for CI assessment, using the selected and calculated fuel properties. Twenty-three aviation fuels from literatures were collected and, using FA, model equations explaining the CI tendency of the aviation fuels were derived, and their respective factor scores were calculated. The model was applied to the 14 fuels in this study, and their respective factor scores were calculated. All the fuels were ranked using the factor score from the best to worst.

Abstract In view of the traditional constant spacing policy (CSP) can’t maximize the fuel saving rate of the truck platoon when choosing the smaller desired vehicle spacing as the control target, a new control strategy is proposed in this article. This strategy dramatically reduces the fuel consumption of the truck platoon from the start to the formation of a stable platoon, thus greatly increasing the fuel saving rate of the platoon. To prove the effectiveness of the strategy, this article carried out the longitudinal dynamics modeling of the truck and the modeling of the fuel consumption model of engine first. Longitudinal dynamics modeling establishes the dynamic equations for truck braking and nonbraking. The fuel consumption model of engine is built using a three-dimensional map. Second, the design of the controller is described. The controller calculates the desired acceleration of the following vehicle based on the speed error and the following distance error.

SCOPE IS UNAVAILABLE.

Engineers and managers involved with product development are continually challenged to reduce time to market, minimize warranty costs, and increase product quality. This results in less time for testing, which means the need for effective accelerated test procedures has never been greater. Accelerating your testing program sounds great, but how do you begin? This course starts by taking a look at statistical models for reliability testing. It looks specifically at how sample size and testing timeframe affect what you’re able to do versus what you'd ideally do with more time and money.

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Process specification for arc wire directed energy deposition (AW-DED) process.

This document addresses measurement uncertainty and consumer risk as they relate to AS8879 thread inspection. It describes the rationale, theory and methodology used to generate the technical content of the AS5870. The document describes how to calculate measurement consumer risk. It documents all of the calculation methods which industry employs today to calculate what is commonly called measurement uncertainty (Appendices A, B, C, D, E and F). These, in turn, are used to calculate measurement uncertainty ratios which are required inputs to calculate measurement consumer risk. Users of this document can apply the information described herein for the evaluation of the capability of their measurements based on the measurement consumer risk. It involves the analysis of the measurement (product) distribution and biases of both the product and measurement system distributions. It protects the consumer from the worst case distribution results.

This concept for measuring worn splines provides a direct wear depth dimension by utilizing the unworn involute surface as a contact point from which to measure the depth of wear on the spline tooth at the pitch diameter. Fig. 1 shows spline wear patterns and pitch diameter gaging points.

This publication formally cautions against terminating nickel coated wire with tin plated insulated or uninsulated crimped solderless terminations.

This Aerospace Recommended Practice outlines requirements for high temperature insulated crimp style terminal lugs for use in electrical wiring in ground or flight equipment.

This document covers all metal, self-locking wrenching nuts, plate nuts, shank nuts, and gang channel nuts made from a corrosion and heat resistant steel of the type identified under the Unified Numbering System as UNS S66286 and of 160 ksi tensile strength at room temperature, with maximum test temperature of parts at 1200 °F.

This document addresses AS8879 thread inspection issues relating to selection, usage and capability of gages. It addresses the selection of calibrated measurement gages, the need for defined quality metrics, the methodology of determining the appropriate guardband factors, and the minimum inspection requirements for single element pitch diameter gages. Users of this document shall apply the information described herein for the evaluation of the capability of their measurements based on the measurement consumer risk. It involves the analysis of the measurement (product) distribution and biases of both the product and measurement system distributions. It protects the consumer from the worst case distribution results. A whitepaper has been developed to provide supporting documentation and the rationale used in the development of this standard. This whitepaper will be published by the SAE as an Aerospace Information Report (AIR6553).

This SAE standard provides manufacturers/marketers, testing facilities, and providers of technician training with a procedure for certifying compliance with the applicable standard. Manufacturers/marketers or sellers who advertise their products as certified to an SAE J standard shall follow this procedure. Certification of a product is voluntary; however, this certification process is mandatory for those advertising meeting SAE standard(s) requirements. Only certifying to this standard allows those claiming compliance to advertise that their product (unit), component, or service technician training meets all requirements of the applicable SAE standard. Certification of compliance to this and the appropriate standard and use of the SAE label on the product shall only be permitted after all the required information has been submitted to SAE International and it has been posted on the SAE website.

This SAE Standard includes complete general and dimensional specifications for those types of pipe, filler, and drain plugs (shown in Figures 1 to 6 and Tables 1 to 4) commonly used in automotive and related industrial applications.