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Meet like-minded mobility engineersto discuss new legislation and regulations around thermal management, emissions control, safety, and energy conservation.

Meet like-minded mobility engineersto discuss new legislation and regulations around thermal management, emissions control, safety, and energy conservation.

If you’re working to balance the implementation of today’s urban ground mobility (UGM) vehicles with tomorrow’s biggest challenges and opportunities, then you belong at the premier of SAE’s Urban Ground Mobility Digital Summit.

If you’re working to balance the implementation of today’s urban ground mobility (UGM) vehicles with tomorrow’s biggest challenges and opportunities, then you belong at the premier of SAE’s Urban Ground Mobility Digital Summit.

PF&L is priority event for mobility professionals that specialize in powertrain, fuels, lubricants technology, including OEM and Tier 1 component suppliers Light medium and heavy-duty vehicle system and product design engineers.

This paper reports comparative results for liquid phase versus gaseous phase port injection in a single cylinder engine. It follows previous research in a multi-cylinder engine where liquid phase was found to have advantages over gas phase at most operating conditions. Significant variations in cylinder to cylinder mixture distribution were found for both phases and leading to uncertainty in the findings. The uncertainty was avoided in this paper as in the engine used, a high speed Waukesha ASTM CFR, identical manifold conditions could be assured and MBT spark found for each fuel supply system over a wide range of mixtures. These were extended to lean burn conditions where gaseous fuelling in the multi-cylinder engine had been reported to be at least an equal performer to liquid phase. The experimental data confirm the power and efficiency advantages of liquid phase injection over gas phase injection and carburetion in multi-cylinder engine tests.

The difficulties encountered in charging batteries over wide temperature ranges have long been recognized. This paper discusses the concept of charge acceptance of batteries and its relationship to the gas pressure developed within sealed batteries. A newly developed system of pressure control charging is described together with its performance over wide temperature ranges. This system completely prevents overcharging at high temperatures and assures full battery capacity down to extremely low temperatures.

Fast charging is attractive to battery electric vehicle (BEV) drivers for its ability to enable long-distance travel and to quickly recharge depleted batteries on short notice. However, such aggressive charging and the sustained vehicle operation that results could lead to excessive battery temperatures and degradation. Properly assessing the consequences of fast charging requires accounting for disparate cycling, heating, and aging of individual cells in large BEV packs when subjected to realistic travel patterns, usage of fast chargers, and climates over long durations (i.e., years). The U.S. Department of Energy's Vehicle Technologies Office has supported the National Renewable Energy Laboratory's development of BLAST-V-the Battery Lifetime Analysis and Simulation Tool for Vehicles-to create a tool capable of accounting for all of these factors. We present on the findings of applying this tool to realistic fast charge scenarios.

A new and unique electric vehicle powertrain model based on bidirectional power flow for propel and regenerative brake power capture is developed and applied to production battery electric vehicles. The model is based on a Willans line model to relate power input from the battery and power output to tractive effort, with one set of parameters (marginal efficiency and an offset loss) for the bidirectional power flow through the powertrain. An electric accessory load is included for the propel, brake and idle phases of vehicle operation. In addition, regenerative brake energy capture is limited with a regen fraction (where the balance goes to friction braking), a power limit, and a low-speed cutoff limit. The purpose of the model is to predict energy consumption and range using only tractive effort based on EPA published road load and test mass (test car list data) and vehicle powertrain parameters derived from EPA reported unadjusted UDDS and HWFET energy consumption.

Abstract Energy management strategies for charge-sustaining hybrid electric vehicles reduce fuel consumption and maintain battery pack state of charge while meeting driver output power demand. The equivalent consumption minimization strategy is a real-time energy management strategy that makes use of an equivalence ratio to quantify electric power consumption in terms of fuel power consumption. The magnitude of the equivalence ratio determines the hybrid electric vehicle mode of operation and influences the ability of the energy management strategy to reduce fuel consumption as well as maintain the battery pack state of charge. The equivalent consumption minimization strategy in this article uses three Willans line models, which have an associated marginal efficiency and constant offset, to model the performance in the hybrid electric vehicle controller.

Methyl esters from vegetable oils (biodiesel) are very attractive as alternative fuels for combustion in direct injection compression-ignition (diesel) engines. Biodiesel fuels have low-temperature flow properties that limit utilization during cooler weather in moderate temperature climates. Although winterization reduces the cloud point (CP) of methyl soyate from 0 to -2O°C, liquid product yields were relatively low (0.30-0.33 g/g). Winterization of methyl soyate-cold flow improver mixtures decreased CP by -11°C and increased yields to 0.80-0.87 g/g. Winterization of methyl soyate from hexane and isopropanol solvents gave similar results. Differential scanning calorimetry (DSC) analyses showed that nucleation mechanisms of methyl esters were significantly affected by winterization.

This paper presents an overview of a new class of wireless acceleration sensor chips being developed by Evigia Systems and Air Force Research Laboratory (AFRL) that can record the magnitude and duration of exposure to external impact without requiring any battery or any other external power source. The combination of the magnitude and duration of the acceleration event provides the information needed for quantification of the impact energy after extracting the recorded data from the sensor array. The light-weight, small form-factor, and wireless link features of these chips enables them to be readily inserted in earplugs, helmets, protective gear, on sections of vehicles. Further, their low cost, make them well suited for the Go-Kart, Sprint Car, Rally and Motocross races where the budgets are lower than IRL or NASCAR.

Due to the rapid development in the technological aspect of the autonomous vehicle (AV), there is a compelling need for research in the field vehicle efficiency and emission reduction without affecting the performance, safety and reliability of the vehicle. Electric vehicle (EV) with rechargeable battery has been proved to be a practical solution for the above problem. In order to utilize the maximum capacity of the battery, a proper power management and control mechanism need to be developed such that it does not affect the performance, reliability and safety of vehicle. Different optimization techniques along with deterministic dynamic programming (DDP) approach are used for the power distribution and management control. The battery-operated electric vehicle can be recharged either by plug-in a wired connection or by the inductive mean (i.e. wirelessly) with the help of the electromagnetic field energy.

This article focuses on the wireless transfer of energy. It describes the operation of a transformer without magnetic circuit associated with a resonant inverter to meet the constraints imposed by mobile sources (catenaries with magnetic induction to power electric vehicles). The receiving and transmitting units consist of an air-gap transformer and a generator who feeds the transformer. In this article, we show how to determine the transformer's parameters and configuration needed for this transfer to be efficient. The transformer is fed by a half-bridge converter for serial resonant load. The primary winding of the transformer is fixed on the ground. The secondary winding can move horizontally in a parallel plane of that of the primary. This application targets mainly the transfer of static electricity for the charging of batteries and super capacitors in electric cars and trams.

“Zero Emission Vehicles” in the form of pure electric vehicles are quite feasible and useful for limited cruising ranges. However, market success depends on customer acceptance. Studies show, that customers expect electric vehicles with driving performance similar to conventional vehicles while comparable cruising ranges should be available at low additional cost. With currently available batteries using lithium ion technology a gravimetric energy density of only one percent of the energy density of gasoline or diesel can be reached. With respect to acceptable additional costs this effect leads to significant reduction of the cruising range. For various reasons such as battery aging, demand for heating, traffic jams, etc., this already decreased cruising range is further reduced. In such cases electrical energy can be generated with a demand oriented (down-) sized combustion engine, a so called “Range Extender”.

Several studies have been performed to investigate the effects of using hydrogen in spark ignition (SI) engines. One general conclusion that emerged was that stoichiometric operation of premixed charge hydrogen engines features increased losses compared to other fuels such as methane. Most studies attribute this higher loss to increased rates of heat transfer from the working fluid to the combustion chamber walls. Indeed, heat flux measurements during combustion and expansion recorded much higher values for hydrogen compared to methane stoichiometric operation. With regard to fluid properties, using the same net heat release equation as for gasoline engines results in an over prediction of heat losses to the combustion chamber walls. Also, the variation of specific heats ratio greatly influences calculated values for the rate of heat release. Therefore, a more detailed analysis of heat losses is required when comparing hydrogen to other fuels.

Using the overall efficiency obtained with today’s automotive power plants on the U.S. Metro Route as a baseline for comparison purposes, this paper reviews the major efficiency opportunities available in the next decade for a wide variety of automotive engine candidates. The impact of a variety of alternate fuels on candidate engine thermal efficiency is also presented. A family of continuously variable transmissions, having different levels of efficiency, are then used to project the overall efficiency of these engine candidates and fuels on the U.S. Metro Route in the 1990+ time frame. The direction of engine design, material and control trends during this time interval are also discussed.

The AS6224 specification covers environment resistant, permanent insulation repair sleeves for repairing different types of insulation damages of wire or cable jackets in installed applications. The repair sleeve is intended to repair damaged primary wire or cable jacket covers where the shielding and wire conductors are not damaged.

The experimental XA-100 is a 5-passenger 4-door Chevrolet Corsica that has been retrofitted with an electric-motor propulsion system, batteries, and an on-board engine/alternator system. The XA-100 is designed 1) to travel on around-town and short freeway commute trips on battery power alone with zero exhaust emissions (zero-emissions vehicle (ZEV)) and 2) to travel as an ultra-low-emissions vehicle (ULEV) on long distance trips using an on-board engine/alternator (i.e., an auxiliary power unit (APU)) for electric power. In all other respects (e.g., performance, handling, user interface), the XA-100 is designed to retain the characteristics of the conventional Corsica to the greatest degree possible. The XA-100 was developed as a result of research sponsored in part by the California Energy Commission (CEC), with labor donated by members of the Electric Auto Association (EAA) and faculty, staff and students of Stanford University.