Analysis of $$\hbox {CO}_2$$ reduction potentials and component load collectives of 48 V-hybrids under real-driving conditions

Abstract Tread pattern wear is predicted by using an explicit finite element model (FEM) and compared with the indoor drum test results under a set of actual driving conditions. One pattern is used to determine the wear rate equation, which is composed of slip velocity and tangential stress under a single driving condition. Two other patterns with the same size (225/45ZR17) and profile are used to be simulated and compared with the indoor wear test results under the actual driving conditions. As a study on the rubber wear rate equation, trial wear rates are assumed by several constitutive equations and each trial wear rate is integrated along time to yield the total accumulated wear under a selected single cornering condition. The trial constitutive equations are defined by independently varying each exponent of slip velocity and tangential stress. The integrated results are compared with the indoor test results, and the best matching constitutive equation for wear is selected for the following wear simulation of two other patterns under actual driving conditions. Tens of thousands of driving conditions of a tire are categorized into a small number of simplified conditions by a suggested simplification procedure which considers the driving condition frequency and weighting function. Both of these simplified conditions and the original actual conditions are tested on the indoor drum test machines. The two results can be regarded to be in good agreement if the deviation that exists in the data is mainly due to the difference in the test velocity. Therefore, the simplification procedure is justified. By applying the selected wear rate equation and the simplified driving conditions to the explicit FEM simulation, the simulated wear results for the two patterns show good match with the actual indoor wear results.

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Prediction of Tire Tread Wear with FEM Steady State Rolling Contact Simulation

Tire Science and Technology ◽

10.2346/1.2135268 ◽

2003 ◽

Vol 31 (3) ◽

pp. 189-202 ◽

Cited By ~ 24

Author(s):

D. Zheng

Keyword(s):

Weight Loss ◽

Steady State ◽

Cross Section ◽

Rolling Contact ◽

Dynamic Simulations ◽

Element Analysis ◽

Vehicle Acceleration ◽

Steady State Rolling ◽

Driving Conditions ◽

Rate Profile

Abstract A procedure based on steady state rolling contact Finite Element Analysis (FEM) has been developed to predict tire cross section tread wear profile under specified vehicle driving conditions. This procedure not only considers the tire construction effects, it also includes the effects of materials, vehicle setup, test course, and driver's driving style. In this algorithm, the vehicle driving conditions are represented by the vehicle acceleration histogram. Vehicle dynamic simulations are done to transform the acceleration histogram into tire loading condition distributions for each tire position. Tire weight loss rates for different vehicle accelerations are generated based on a steady state rolling contact simulation algorithm. Combining the weight loss rate and the vehicle acceleration histogram, nine typical tire loading conditions are chosen with different weight factors to represent tire usage conditions. It is discovered that the tire tread wear rate profile is changing continuously as the tire is worn. Simulation of a new tire alone cannot be used to predict the tire cross-section tread wear profile. For this reason, an incremental tread wear simulation procedure is performed to predict the tire cross section tread wear profile. Compared with actual tire cross-section tread wear profiles, good results are obtained from the simulations.

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Effect of Polymer, Road Surface, and Driving Conditions on Wear Surface Characteristics of Tire Treads

Tire Science and Technology ◽

10.2346/1.2167171 ◽

1973 ◽

Vol 1 (4) ◽

pp. 354-362 ◽

Cited By ~ 2

Author(s):

F. R. Martin ◽

P. H. Biddison

Keyword(s):

Wear Surface ◽

Surface Characteristics ◽

Road Surface ◽

The Other ◽

Mechanical Degradation ◽

Textured Surface ◽

Test Track ◽

Driving Conditions ◽

Styrene Butadiene ◽

Cylindrical Particles

Abstract Treads made with emulsion styrene-butadiene copolymer (SBR), solution SBR, polybutadiene (BR), and a 60/40 emulsion SBR/BR mixture were built as four-way tread sections on G78-15 belted bias tires, which were driven over both concrete and gravel-textured highways and on a small, circular, concrete test track. The tires were front mounted. When driven on concrete highway, all except the BR tread had either crumbled- or liquid-appearing surfaces, thought to have been formed by mechanical degradation or fatigue. When cornered on concrete, these materials formed small cylindrical particles or rolls. The BR tread had a smooth, granular-textured surface when driven on concrete highway and a ridge or sawtooth abrasion pattern when cornered on concrete. All the materials appeared rough and torn when run on gravel-textured highway. The differences in wear surface formed on BR tread and the other three are thought to be due primarily to the relatively high resilience of BR.

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Cobaloxime-Based Double Complex Salts as Efficient and Versatile Catalysts for the Light-Driven Hydrogen Evolution Reaction

10.26434/chemrxiv.11537661 ◽

2020 ◽

Author(s):

Elisabeth Hofmeister ◽

Jisoo Woo ◽

Tobias Ullrich ◽

Lydia Petermann ◽

Kevin Hanus ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Systematic Study ◽

Cobalt Complexes ◽

Spectroscopic Studies ◽

Double Complex ◽

Double Complex Salts ◽

Noble Metal Catalysts ◽

Reduction Potentials ◽

Complex Salts

Cobaloximes and their BF2-bridged analogues have emerged as promising non-noble metal catalysts for the photocatalytic hydrogen evolution reaction (HER). Herein we report the serendipitous discovery that double complex salts such as [Co(dmgh)2py2]+[Co(dmgBPh2)2Cl2]- can be obtained in good yields by treatment of commercially available [Co(dmgh)2pyCl] with triarylboranes. A systematic study on the use of such double complex salts and their single salts with simple counterions as photocatalysts revealed HER activities comparable or superior to existing cobaloxime catalysts and suggests ample opportunities for this compound class in catalyst/photosensitizer dyads and immobilized architectures. Preliminary electrochemical and spectroscopic studies indicate that one key advantage of these charged cobalt complexes is that the reduction potentials as well as the electrostatic interaction with charged photosensitizers can be tuned.

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Phosphoryl- and Phosphonium-Bridged Viologens as Stable Two- and Three-Electron Acceptors for Organic Electrodes

10.26434/chemrxiv.12711770.v1 ◽

2020 ◽

Author(s):

Colin R. Bridges ◽

Andryj M. Borys ◽

Vanessa Béland ◽

Joshua R. Gaffen ◽

Thomas Baumgartner

Keyword(s):

Molecular Weight ◽

Organic Molecules ◽

Electrode Materials ◽

High Energy ◽

Electron Acceptors ◽

Low Molecular Weight ◽

Reduction Potentials ◽

Organic Electrode ◽

High Reduction ◽

High Specific Energy

Low molecular weight organic molecules that can accept multiple electrons at high reduction potentials are sought after as electrode materials for high-energy sustainable batteries. To date their synthesis has been difficult, and organic scaffolds for electron donors significantly outnumber electron acceptors. Herein, we report two highly electron deficient phosphaviologen derivatives from a phosphorus-bridged 4,4-bipyridine and characterize their electrochemical properties. Phosphaviologen sulfide (PVS) and P-methyl phosphaviologen (PVM) accept two and three electrons at high reduction potentials, respectively. PVM can reversibly accept 3 electrons between 3-3.6 V vs. Li/Li+ with an equivalent molecular weight of 102 g/(mol e-) (262 mAh/g), making it a promising scaffold for sustainable organic electrode materials having high specific energy densities.

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