Deterministic Simulation of Surfaces in Conformal-Contact Lubrication

This paper describes a simple metal pattern transfer method on glass substrates. Ag metal films were transferred by the conformal contact method at 150°C, which did not require higher pressure than the conventional nano-imprinting method. The important factors affecting quality of transferred metal patterns on glass were the usage of anti-sticking layer on mold surface, thickness of transferred metal films and temperature during contact printing step. Various Ag patterns were transferred onto glass substrate.

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Uncertainty Simulation of Wood Chipping Operation for Bioenergy Based on Queuing Theory

Forests ◽

10.3390/f10090822 ◽

2019 ◽

Vol 10 (9) ◽

pp. 822

Author(s):

Yoshida ◽

Takata

Keyword(s):

Supply Chain ◽

Moisture Content ◽

Queuing Theory ◽

Wood Chip ◽

Stochastic Modelling ◽

Simulation Method ◽

Daily Production ◽

Deterministic Simulation ◽

Loss Compensation ◽

Truck Arrival

Managing uncertainty is the way to secure stability of the supply chain. Uncertainty within chipping operation and chip transportation causes production loss. In the wood chip supply chain for bioenergy, operational uncertainty mainly appears in the moisture content of the material, chipping productivity, and the interval of truck arrival. This study theoretically quantified the loss in wood chip production by applying queuing theory and stochastic modelling. As well as the loss in production, the inefficiency was identified as the idling time of chipper and the queuing time of trucks. The aim of this study is to quantify the influence of three uncertainties on wood chip production. This study simulated the daily chip production using a mobile chipper by applying queuing theory and stochastic modelling of three uncertainties. The result was compared with the result of deterministic simulation which did not consider uncertainty. Uncertainty reduced the production by 14% to 27% compared to the production of deterministic simulation. There were trucks scheduled but not used. The cases using small trucks show the largest daily production amount, but their lead time was the longest. The large truck was sensitive to the moisture content of material because of the balance between payload and volumetric capacity. This simulation method can present a possible loss in production amount and enables to evaluate some ways for the loss compensation quantitatively such as outsourcing or storing buffer. For further development, the data about the interval of truck arrival should be collected from fields and analyzed. We must include the other uncertainties causing technical and operator delays.

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Approximating the influence coefficients of non-planar elastic solids for conformal contact analysis

Tribology International ◽

10.1016/j.triboint.2020.106671 ◽

2021 ◽

Vol 154 ◽

pp. 106671 ◽

Cited By ~ 1

Author(s):

Julio Blanco-Lorenzo ◽

Edwin A.H. Vollebregt ◽

Javier Santamaria ◽

Ernesto G. Vadillo

Keyword(s):

Contact Analysis ◽

Elastic Solids ◽

Influence Coefficients ◽

Conformal Contact

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Comparison of Load Carrying Capacity of Three and Four Lobed Polygonal Shaft and Hub Connection for Constant Grinding Diameter

Volume 9: Mechanics of Solids, Structures and Fluids; NDE, Diagnosis, and Prognosis ◽

10.1115/imece2016-65745 ◽

2016 ◽

Cited By ~ 3

Author(s):

Ravi Bhatta ◽

Wendy Reffeor

Keyword(s):

Carrying Capacity ◽

Power Transmission ◽

Axial Stress ◽

Von Mises Stress ◽

Load Carrying Capacity ◽

Interference Fit ◽

Bending Load ◽

Load Carrying ◽

Von Mises ◽

Conformal Contact

Polygonal shafts are used in power transmission as alternatives to keyed and splined shafts. They are designed using DIN standards. This research explores the loading strength of the standardized three lobed (P3G) and four lobed (P4C) polygonal shafts and hubs manufactured from the same stock size, subjected to torsional bending load at various fits. Due to complex conformal contact (nonlinear model) between the shaft and the hub, there is no analytical solution and, therefore, Finite Element Method had been used to determine the stresses, after validating experimentally and using the DIN standard. From the analysis, it was found that the hub experienced greater stress than the shaft in all cases and the major stress in a polygonal shaft and hub connection is the contact stress. The clearance fit was found to be the most detrimental fit and the interference fit to be the most suitable for larger power transmission. Owing to its small normal axial stress and hub displacement, the P4C clearance fit has its use in low power transmission where a sliding fit is a requirement. The maximum von Mises stress was located below the surface for P4C and P3G clearance fit, suggesting failure from pitting and fretting on these shafts. All of the stresses were found to be higher in P4C than P3G for similar loading. Therefore, for general use, the P3G profile with an interference fit is recommended.

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