Substantiation of the Starter Battery Load Cycle Structure

2021 ◽  
Author(s):  
Andrey Puzakov ◽  
Dmitriy Smirnov
Keyword(s):  
Load Cycle ◽  
Cycle Structure

scholarly journals Dynamics of the Ice-Crushing Process

1988 ◽  
Vol 34 (118) ◽  
pp. 318-326 ◽  
Author(s):  
Ian J. Jordaan ◽  
Garry W. Timco
Keyword(s):  
Ice Sheet ◽  
Load Cycle ◽  
Stored Energy ◽  
Indentation Process ◽  
Ice Particles ◽  
Mode Of Failure ◽  
Indentation Tests ◽  
Energy Exchanges ◽  
The Mean ◽  
Crushed Ice

Abstract During fast indentation tests on ice sheets at constant rates, crushing is commonly observed at appropriate combinations of speed and aspect ratio. An analysis is made of this mode of failure, using as a basis a recently conducted test on an ice sheet under controlled conditions. The variation of load with time is given special attention, and cyclic variation of load is associated with periodic crushing (pulverization) events, followed by clearing of the crushed ice particles. An analysis of the clearing process is summarized in the paper, treating the crushed ice as a viscous material. A detailed analysis of the energy exchanges during the indentation process is given. Elastic variations of stored energy in the indenter and in the ice sheet are calculated; these are relatively minor. The dissipation of energy during a typical load cycle (3 mm movement during 0.05 s) is about 8 J. The energy required to create surfaces of the crushed ice particles is small (0.006 J), as is the work of crushing based on mechanical testing (0.09 J). It is concluded that the process of viscous extrusion of crushed ice is the main seat of energy dissipation, basically as a frictional process. A relationship for the mean thickness of the crushed ice layer is developed, based on energy-balance considerations.

The Algorithm for Graphic Method of Rain-Flow Counting in Programming

2011 ◽  
Vol 225-226 ◽  
pp. 1157-1161 ◽  
Author(s):  
Qing Deng ◽  
Hong Jie Yuan
Keyword(s):  
Computer Program ◽  
Execution Time ◽  
Counting Process ◽  
Load Cycle ◽  
Mean Value ◽  
Graphic Method ◽  
Counting Method ◽  
Starting Point ◽  
Mechanical Basis

In this article, a new algorithm for rain-flow counting method in computer program is introduced. In the whole counting process, this algorithm entirely follows the principle of graphic method of rain-flow counting method, and so it can embodies the mechanical basis of extracting load cycle in rain-flow counting method; during the processing of counting, the information of every load cycle can be accurately recorded, such as starting and ending time, the time of peak or valley, the value of starting point and peak (or valley), mean value and amplitude. Besides, the counting result is in full accordance with the result from graphic method. Compared to four peak-valley method, this algorithm has shorter execution time and higher efficiency.

Fatigue Life Recovery via Laser Shock Peening in Mechanically Damaged Aluminium Sheet; Experiments and Prediction Models

2014 ◽  
Vol 891-892 ◽  
pp. 980-985 ◽  
Author(s):  
Niall Smyth ◽  
Philip E. Irving
Keyword(s):  
Residual Stress ◽  
Fatigue Life ◽  
Prediction Models ◽  
Load Cycle ◽  
Laser Shock Peening ◽  
Stress Fields ◽  
Hole Drilling ◽  
Laser Shock ◽  
Aluminium Sheet ◽  
Shock Peening

This paper reports the effectiveness of residual stress fields induced by laser shock peening (LSP) to recover pristine fatigue life. Scratches 50 and 150 μm deep with 5 μm root radii were introduced into samples of 2024-T351 aluminium sheet 2 mm thick using a diamond tipped tool. LSP was applied along the scratch in a band 5 mm wide. Residual stress fields induced were measured using incremental hole drilling. Compressive residual stress at the surface was-78 MPa increasing to-204 MPa at a depth of 220 μm. Fatigue tests were performed on peened, unpeened, pristine and scribed samples. Scratches reduced fatigue lives by factors up to 22 and LSP restored 74% of pristine life. Unpeened samples fractured at the scratches however peened samples did not fracture at the scratches but instead on the untreated rear face of the samples. Crack initiation still occurred at the root of the scribes on or close to the first load cycle in both peened and unpeened samples. In peened samples the crack at the root of the scribe did not progress to failure, suggesting that residual stress did not affect initiation behaviour but instead FCGR. A residual stress model is presented to predict crack behaviour in peened samples.

scholarly journals Taxing Capital? Not a Bad Idea After All!

2009 ◽  
Vol 99 (1) ◽  
pp. 25-48 ◽  
Author(s):  
Juan Carlos Conesa ◽  
Sagiri Kitao ◽  
Dirk Krueger
Keyword(s):  
Income Tax ◽  
Labor Income ◽  
Income Shocks ◽  
Capital Income ◽  
Overlapping Generations Model ◽  
Cycle Structure ◽  
Tax Rate ◽  
Average Household Income ◽  
Optimal Capital

We quantitatively characterize the optimal capital and labor income tax in an overlapping generations model with idiosyncratic, uninsurable income shocks and permanent productivity differences of households. The optimal capital income tax rate is significantly positive at 36 percent. The optimal progressive labor income tax is, roughly, a flat tax of 23 percent with a deduction of $7,200 (relative to average household income of $42,000). The high optimal capital income tax is mainly driven by the life-cycle structure of the model, whereas the optimal progressivity of the labor income tax is attributable to the insurance and redistribution role of the tax system. (JEL E13, H21, H24, H25)

Symmetric Single Rod Cylinders With Variable Piston Area? A Comprehensive Approach to the Right Solution

2018 ◽  
Author(s):  
Giacomo Kolks ◽  
Jürgen Weber
Keyword(s):  
Experimental Validation ◽  
Design Space ◽  
Solution Space ◽  
Hydraulic Cylinder ◽  
Load Cycle ◽  
Displacement Control ◽  
Comprehensive Description ◽  
Subsequent Step ◽  
Variable Displacement ◽  
The Right

In contrast to rotational hydraulic displacement units, such as pumps or motors, conventional hydraulic cylinder actuators do not allow a continuous variation of their displacement quantity: the piston area is regarded constant. In order to adapt to varying load and velocity requirements in a load cycle under torque restrictions of the driving motor, cylinder drives often implement pumps with variable displacement. In this paper, cylinders with discretely variable effective piston area by means of variable circuitry of multi-chamber cylinders are discussed. Hydraulic symmetry or constant asymmetry of the hydraulic cylinder are traits of the cylinder that are required to fit the cylinder to pump structures for closed-circuit displacement control, as given in electro-hydrostatic compact drives (ECD). A methodology to generate all possible solutions of variable area cylinders under the constraint of ECD requirements is proposed. A comprehensive description of the solution space is given, based on combinatorics and solution of equation systems. The methodology dealing with abstract cylinder areas is backed up by a general approach to describe the mechanical cylinder design space to combine multiple cylinder areas in one structural unit. Examples for design of three and four area cylinders are given and results are discussed. The paper concludes with the development of a demonstrator design to allow experimental validation in a subsequent step.

scholarly journals On the cycle structure of Mallows permutations

2018 ◽  
Vol 46 (2) ◽  
pp. 1114-1169 ◽  
Author(s):  
Alexey Gladkich ◽  
Ron Peled
Keyword(s):  
Cycle Structure

Models for Calculating the Effect of Environment on Fatigue Life (Fen) for Complex Waveforms and/or Non-Isothermal Conditions

2017 ◽  
Author(s):  
Chris Currie ◽  
Andrew Morley ◽  
Norman Platts ◽  
Marius Twite ◽  
Keith Wright
Keyword(s):  
Strain Rate ◽  
Test Data ◽  
Deleterious Effect ◽  
Load Cycle ◽  
Temperature Cycling ◽  
Plant Materials ◽  
Endurance Testing ◽  
Approach Method ◽  
Rate Method ◽  
Fatigue Endurance

Environmentally assisted fatigue of nuclear plant materials in the Pressurised Water Reactor (PWR) coolant environment is a phenomenon that has been extensively studied over the past 30 years. Methods for accounting for the PWR environment in an ASME III fatigue assessment are presented in NUREG/CR-6909. The deleterious effect of environment is described through a Fen factor dependent upon strain rate, temperature and the dissolved oxygen content of the water. The formulae which describe the Fen are based upon correlations observed in test data predominantly from tests conducted with constant temperature and strain rate (triangular or sawtooth loading). Actual loading histories encountered during service are far more complex, with both strain rate and temperature, and therefore Fen, varying through the cycle. NUREG/CR-6909 recommends a modified rate approach method for accounting for this, whereby the load cycle is broken up into a number of strain increments and then integrated to give the Fen for the cycle. There is a substantial and growing body of data for conditions in which the strain rate or temperature or both changes. The NUREG/CR-6909 modified rate approach does not generally perform well in describing the deleterious effect of environment in these complex conditions. In particular, the modified rate approach does not predict a difference in life when the temperature is varied in-phase or out-of-phase with the strain waveform, or when the slow portion of the strain rate is moved from the top to the bottom of the waveform. This paper presents new data from strain-controlled fatigue endurance testing of two casts of 304L with complex waveforms and temperature cycling. The paper then presents and compares a number of models for integrating the Fen through the cycle, including methods which weight Fen increments depending on position in the strain cycle. It is concluded that greater weighting on the environmental effect in the top of the cycle is necessary to describe the differences in life observed. This is further validated by a review of test data in the wider literature. An improved method is presented to account for the effects of the PWR environment on fatigue lives of austenitic stainless steel materials, which has similarities to the “Weighted K Rate” method previously presented by Rolls-Royce, PVP2016-63497, for environmentally assisted fatigue crack growth.

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