scholarly journals Control of Final Part Dimensions in Polymer Extrusion Using a Variable-Geometry Die

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Lawrence W. Funke ◽  
James P. Schmiedeler
Keyword(s):  
Cross Section ◽  
Iterative Learning Control ◽  
Learning Algorithm ◽  
Final Part ◽  
Variable Geometry ◽  
Trial And Error ◽  
Polymer Extrusion ◽  
Automated Control ◽  
Simulation Results ◽  
Part Dimension

Parts made via polymer extrusion are currently limited to a constant cross section. Additionally, the process is difficult to control, so desired final part dimensions are often achieved via a manual trial-and-error approach to parameter adjustment. This work seeks to increase the capability of polymer extrusion by using iterative learning control (ILC) to regulate the final width of a rectangular part through changing the width of a simple variable-geometry die. Simulation results determine the appropriateness of the learning algorithm and gains to be used in experiment. A prototype die on a production extruder was used to demonstrate the effectiveness of the approach. These experiments achieved automated control over both gross change in shape and final part dimension when the puller speed was held constant, which has not been seen previously in the literature.

Iterative Learning Control for a Class of Modeling Undesirable Single Degree of Freedom System

2014 ◽  
Vol 538 ◽  
pp. 379-382
Author(s):  
Wei Zhou ◽  
Bao Bin Liu
Keyword(s):  
Iterative Learning Control ◽  
Learning Algorithm ◽  
Learning Control ◽  
Iterative Learning ◽  
Degree Of Freedom ◽  
Control Input ◽  
Convergence Properties ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Simulation Results

A class of modeling undesirable single degree of freedom system is studied by using iterative learning control. The proposed iterative learning algorithm constantly updates the control input according to output error until the desired output occurred. So the system with designed controller can achieve perfect accuracy. We have proved convergence properties in iteration domain and simulation results demonstrate the effectiveness of the presented method.

Variable Geometry Dies for Polymer Extrusion

2014 ◽  
Author(s):  
Kevin S. Giaier ◽  
David H. Myszka ◽  
Wesley P. Kramer ◽  
Andrew P. Murray
Keyword(s):  
Cross Section ◽  
Low Cost ◽  
Experimental Studies ◽  
Design Guidelines ◽  
Variable Geometry ◽  
Polymer Extrusion ◽  
High Production Rate ◽  
High Production ◽  
Plastic Parts ◽  
Extrusion Technology

This paper presents the development of variable geometry dies that enable the extrusion of plastic parts with a varying cross section. Extrusion accounts for 40% of all manufactured plastic parts because it is a relatively low-cost and high-production-rate process. Conventional polymer extrusion technology, however, is limited to fixed dies that produce continuous plastic products of constant cross section defined by the die exit profile. A shape-changing die allows the cross section of the extruded part to change over its length, thereby introducing the capacity to manufacture plastic faster and with lower tooling costs than injection molding. This paper discusses design guidelines that were developed for movable die features including revolute and prismatic joint details, land length, and the management of die leakage. To assess these guidelines, multiple dies have been designed and constructed to include an arbitrary four-sided exit profile where changes were made to the internal angles and length of sides as the extruder was operating. Experimental studies were conducted by using different extruder line settings and time between die movements. Test results are presented that include shape repeatability and the relationship between extrudate profile and die exit geometry.

scholarly journals Nanodevices Tend to Be Round

Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 330
Author(s):  
Georges Pananakakis ◽  
Gérard Ghibaudo ◽  
Sorin Cristoloveanu
Keyword(s):  
Diffusion Process ◽  
Thermal Diffusion ◽  
Cross Section ◽  
Gate Voltage ◽  
Supportive Evidence ◽  
Inversion Mode ◽  
Nanowire Transistor ◽  
Junctionless Transistor ◽  
Simulation Results ◽  
Thermal Diffusion Process

Under several circumstances, a nanowire transistor with a square cross-section behaves as a circular. Taking the Gate-All-Around junctionless transistor as a primary example, we investigate the transition of the conductive region from square to circle-like. In this case, the metamorphosis is accentuated by smaller size, lower doping, and higher gate voltage. After defining the geometrical criterion for square-to-circle shift, simulation results are used to document the main consequences. This transition occurs naturally in nanowires thinner than 50 nm. The results are rather universal, and supportive evidence is gathered from inversion-mode Gate-All-Around (GAA) MOSFETs as well as from thermal diffusion process.

Iterative learning algorithm with a quadratic criterion for linear time-varying systems

2002 ◽  
Vol 216 (3) ◽  
pp. 309-316 ◽  
Author(s):  
S N Huang ◽  
K K Tan ◽  
T H Lee
Keyword(s):  
Learning Algorithm ◽  
Linear Time ◽  
Tracking Error ◽  
Iterative Learning ◽  
Tracking Performance ◽  
Time Varying ◽  
Control Scheme ◽  
Time Varying Systems ◽  
Simulation Results ◽  
Learning Law

A novel iterative learning controller for linear time-varying systems is developed. The learning law is derived on the basis of a quadratic criterion. This control scheme does not include package information. The advantage of the proposed learning law is that the convergence is guaranteed without the need for empirical choice of parameters. Furthermore, the tracking error on the final iteration will be a class K function of the bounds on the uncertainties. Finally, simulation results reveal that the proposed control has a good setpoint tracking performance.

The TP Chromatic Aberration Estimation by Using Neural Networks

2011 ◽  
Vol 121-126 ◽  
pp. 4239-4243 ◽  
Author(s):  
Du Jou Huang ◽  
Yu Ju Chen ◽  
Huang Chu Huang ◽  
Yu An Lin ◽  
Rey Chue Hwang
Keyword(s):  
Neural Networks ◽  
Learning Algorithm ◽  
Back Propagation ◽  
Physical Property ◽  
Chromatic Aberration ◽  
Neural Model ◽  
Artificial Intelligent ◽  
Error Back Propagation ◽  
The Neural Networks ◽  
Simulation Results

The chromatic aberration estimations of touch panel (TP) film by using neural networks are presented in this paper. The neural networks with error back-propagation (BP) learning algorithm were used to catch the complex relationship between the chromatic aberration, i.e., L.A.B. values, and the relative parameters of TP decoration film. An artificial intelligent (AI) estimator based on neural model for the estimation of physical property of TP film is expected to be developed. From the simulation results shown, the estimations of chromatic aberration of TP film are very accurate. In other words, such an AI estimator is quite promising and potential in commercial using.

A Neural Root Finder of Polynomials Based on Root Moments

2004 ◽  
Vol 16 (8) ◽  
pp. 1721-1762 ◽  
Author(s):  
De-Shuang Huang ◽  
Horace H.S. Ip ◽  
Zheru Chi
Keyword(s):  
Learning Algorithm ◽  
A Priori ◽  
Feedforward Neural Networks ◽  
A Priori Information ◽  
Backpropagation Algorithm ◽  
Constrained Learning ◽  
Roots Of Polynomials ◽  
Simulation Results ◽  
Priori Information ◽  
Coefficient Method

This letter proposes a novel neural root finder based on the root moment method (RMM) to find the arbitrary roots (including complex ones) of arbitrary polynomials. This neural root finder (NRF) was designed based on feedforward neural networks (FNN) and trained with a constrained learning algorithm (CLA). Specifically, we have incorporated the a priori information about the root moments of polynomials into the conventional backpropagation algorithm (BPA), to construct a new CLA. The resulting NRF is shown to be able to rapidly estimate the distributions of roots of polynomials. We study and compare the advantage of the RMM-based NRF over the previous root coefficient method—based NRF and the traditional Muller and Laguerre methods as well as the mathematica roots function, and the behaviors, the accuracies of the resulting root finders, and their training speeds of two specific structures corresponding to this FNN root finder: the log σand the σ FNN. We also analyze the effects of the three controlling parameters {δP0 θp η} with the CLA on the two NRFs theoretically and experimentally. Finally, we present computer simulation results to support our claims.

Cross-Section Shape Optimization of Expandable Cased-Hole Liners

2010 ◽  
Vol 156-157 ◽  
pp. 1141-1145
Author(s):  
Ben Ma ◽  
Hai Qing Li ◽  
Xu Deng ◽  
Min Li
Keyword(s):  
Cross Section ◽  
Branch Pipe ◽  
Field Tests ◽  
Forming Process ◽  
Molding Process ◽  
Compression Process ◽  
Proper Position ◽  
Cross Section Shape ◽  
Section Shape ◽  
Simulation Results

Expandable cased-hole liners is to solve the sealing problem of level six multilateral wells. It is a trigeminal expandable tube which is usually prefabricated on the ground and re-expanded when placed in the proper position. In this paper, the trigeminal expandable tubular compression molding process of the pre-forming stage is mainly studied. In this compression process, both sides of the branch pipe should be compressed to a certain shape in order to successfully enter the main borehole; meanwhile, we want to make sure that failures such as rupture do not occur in the subsequent expansion process. According to the theory about sheet metal bending forming process, three different shapes of the mold are designed to control the cross-section shape of the compressed trigeminal expandable tube so that it meets the application requirements. Rack-shaped cross-section is finally selected as a reference of the best through simulation of compression process and comparative analysis of simulation results. At last, field tests show that this cross-section shape is compatible with the theoretical and simulation results.

Design of Printed Circuit Heat Exchanger (PCHE) for LNG Re-Gasification System

2017 ◽  
Author(s):  
Seok Ho Yoon ◽  
Jeong Heon Shin ◽  
Dong Ho Kim ◽  
Jun Seok Choi
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Optimal Design ◽  
Cross Section ◽  
Diffusion Bonding ◽  
Analytical Calculation ◽  
Analytical Tool ◽  
Printed Circuit ◽  
Simulation Results ◽  
Semicircular Cross Section

In this paper, we present the ongoing process of the research and development of the Printed Circuit Heat Exchanger (PCHE) on Floating Storage Regasification Unit (FSRU). We performed a structural simulation work to find the optimal design of fluid channels on heat transfer plates, fabricated the heat transfer plates, and calculated the capacity of the PCHE using our analytical tool. In the simulation work, the plates having channels of 1 mm semicircular cross section were designed by varying the wall thickness between channels. At a temperature, 1373 K, compressing pressures were varied as 30, 85.7, and 500 bars. Based on the simulation results, we fabricated and bonded heat transfer plates using the diffusion bonding equipment which our department developed. Then, the sizing of PCHE was done with analytical calculation for the developing PCHE on FSRU.

scholarly journals Numerical Simulation of A Cubic Spout-Fluid Bed: Influences of Inlet Gas Temperature and Jet to Bed Cross-Section Ratio

2020 ◽  
Vol 18 (3) ◽  
Author(s):  
Ali Rahmani ◽  
Mohsen Tamtaji ◽  
Asghar Molaei Dehkordi
Keyword(s):  
Cross Section ◽  
Circulation Pattern ◽  
Particle Simulation ◽  
Cross Section Ratio ◽  
Gas Temperature ◽  
Section Ratio ◽  
Fluid Bed ◽  
Discrete Particle Simulation ◽  
Simulation Results

AbstractIn this paper, we study the role of inlet gas temperature and jet to bed cross-section ratio on hydrodynamics and circulation patterns of particles in a spout-fluid bed. The system is modeled using CFD-TFM approach based on Eulerian-Eulerian method. Simulation results are validated by experimental data measured by (Link 2008. “PEPT and Discrete Particle Simulation Study of Spout-fluid Bed Regimes.” Aiche Journal 54 (5): 1189–202). First, the sensitivity analysis of simulation results versus the most significant parameters are conducted to find the optimum values for each parameter. Subsequently, the role of inlet gas temperature and cross-section ratios are studied in detail. The simulation results clearly demonstrate that increasing the inlet gas temperature raises particles’ velocity in the bed and affects the circulation pattern in annulus region. Additionally, it is shown that higher gas temperature leads to existence of hot spots in the annulus region. In case of jet to bed cross-section ratio, using larger ratios results in higher velocities and lower pressure drop along the bed.

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