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Due to modern trends in the automotive industry, such as vehicle electrification, light-weighting, reduced NVH (Noise, Vibration and Harshness) packaging space, etc., it is desirable to have a low profile and light-weight acoustic material with multi-functionality. If one single layer of a thin acoustic material can provide comparable absorption and transmission loss to a multilayer treatment, it will benefit the industry by saving weight, packaging space and system cost. Acoustic absorption and sound transmission loss performance of a new dissipative material at reduced weight and thickness is introduced in this paper. The acoustic performance of the material was evaluated by using random incidence absorption and transmission loss as well as in-vehicle experiment. Further potential applications for this material have been identified using the Statistical Energy Analysis (SEA) method with panel leakage considered.

The four-microphone standing wave tube system has proven useful for measuring the absorption and transmission loss of various fibrous and non-fibrous absorbers. The system is fast, repeatable, accurate and compact. This paper discusses the advantages of the four-microphone system for measuring the transmission loss in lateral-flow absorber systems. The original four-microphone round impedance tube system and the migration to a four-microphone square tube system are discussed. The four-microphone square tube system allows effective study of filled and partially filled cavities.

This paper assesses the potential improvement of automotive powertrain technologies 25 years into the future. The powertrain types assessed include naturally-aspirated gasoline engines, turbocharged gasoline engines, diesel engines, gasoline-electric hybrids, and various advanced transmissions. Advancements in aerodynamics, vehicle weight reduction and tire rolling friction are also taken into account. The objective of the comparison is the potential of anticipated improvements in these powertrain technologies for reducing petroleum consumption and greenhouse gas emissions at the same level of performance as current vehicles in the U.S.A. The fuel consumption and performance of future vehicles was estimated using a combination of scaling laws and detailed vehicle simulations. The results indicate that there is significant potential for reduction of fuel consumption for all the powertrains examined.

The transportation sector in the United States is a major contributor to global energy consumption and carbon dioxide emission. To assess the future potentials of different technologies in addressing these two issues, we used a family of simulation programs to predict fuel consumption for passenger cars in 2020. The selected technology combinations that have good market potential and could be in mass production include: advanced gasoline and diesel internal combustion engine vehicles with automatically-shifting clutched transmissions, gasoline, diesel, and compressed natural gas hybrid electric vehicles with continuously variable transmissions, direct hydrogen, gasoline and methanol reformer fuel cell hybrid electric vehicles with direct ratio drive, and battery electric vehicle with direct ratio drive.

To manage the function of a vehicle's engine, transmission, and related subsystems, almost all modern vehicles make use of one or more electronic controllers running embedded software, henceforth referred to as a Powertrain Controller System or PCS. Fully validating this PCS is a necessary step of vehicle development, and the validation process requires extensive amounts of testing. Within the automotive industry, more and more of this validation testing is being performed using Hardware-in-the-Loop (HIL) simulators to automate the extensive test sequences. A HIL simulation typically mates the physical PCS to a closed-loop real time computer simulation of a powertrain. Interfacing the physical PCS hardware to a powertrain simulation requires the HIL simulator to have extensive signal input/output (I/O) electronics and simulated actuator electrical loading.

This paper discusses a new technology for control of solar heat gain in automobiles. Described will be a non-metallic, all-polymeric film, which reflects solar infrared, has high visible light transmission, and an appearance that is clear and colorless. The film is designed to be used in combination with tinted glass, as a component in an overall glazing design. Measured solar control levels are shown to be competitive with metallised film technologies. Prototype windshields and body glass units have been successfully made in a standard autoclave cycle. Constructions were made by using the film as the center component in a five layer glass/pvb/film/pvb/glass laminate. The results of durability, performance, and specification tests are encouraging and will be discussed.

In a recent paper (Hoult & Meador, [1]) a novel method of estimating the costs of parts, and assemblies of parts, was presented. This paper proposed that the metric for increments of cost was the function log (dimension/tolerance). Although such log functions have a history,given in [1], starting with Boltzman and Shannon, it is curious that it arises in cost models. In particular, the thermodynamic basis of information theory, given by Shannon [2], seems quite implausible in the present context. In [1], we called the cost theory “Complexity Theory”, mainly to distinguish it from information theory. A major purpose of the present paper is to present a rigorous argument of how the log function arises in the present context. It happens that the agrument hinges on two key issues: properties of the machine making or assembling the part, and a certain limit process. Neither involves thermodynamic reasoning.

A multilayer acoustic treatment constructed of fibrous acoustic absorption material combined with dissipative acoustic material achieves a low profile and is lightweight and multi-functional, with properties that are desirable for NVH (noise, vibration, and harshness) treatments. The dissipative material consists of microfibers and acoustically active particles; this material was introduced in the last SAE NVH conference: A Novel Dissipative Acoustic Material [1]. In this paper, the acoustic performance of the multilayer treatment was evaluated by using random incidence absorption and transmission loss measurements, as well as in-vehicle experiments. Absorption and transmission loss were additionally modeled using the transmission matrix method (TMM). In the in-vehicle test, an OEM wheelhouse liner with Trim, for an SUV, was evaluated utilizing this new multilayer 3M treatment.