On-Line PVT Properties of Amorphous Polymers

2009 ◽  
Vol 87-88 ◽  
pp. 216-221
Author(s):  
Jian Wang ◽  
Peng Cheng Xie ◽  
Yu Mei Ding ◽  
Wei Min Yang
Keyword(s):  
Amorphous Polymers ◽  
Processing Conditions ◽  
Pvt Properties ◽  
Molding Machine ◽  
Industrial Processing ◽  
Temperature Ranges ◽  
On Line ◽  
Large Length ◽  
Normal Processing ◽  
Good Agreement

Pressure-Volume-Temperature (P-V-T) properties of two amorphous polymers (ABS and PS) were measured by an on-line testing measurement in the temperature ranges from 20 to 150 °C and pressures from 20 to 120 MPa. The on-line testing measurement is based on an injection molding machine (IMM), and it can be used to get P-V-T data of polymers directly with a special testing mold under normal processing conditions. The experimental P-V-T results of amorphous polymers under industrial processing conditions were presented. A new modified two-domain Spencer-Gilmore equation of state (EOS) was developed. The P-V-T properties were correlated by the modified Spencer-Gilmore EOS and a modified two-domain Tait EOS, showing a good agreement with measurements. The effects of sample forms were investigated. A sample with large length diameter ratio is the best one to be measured.

Prediction of Zero-Shear Viscosity of Linear Polybutadienes from the Crossover Point Using Doi-Edwards Theory

1988 ◽  
Vol 61 (5) ◽  
pp. 812-827 ◽  
Author(s):  
Ramesh R. Rahalkar ◽  
Henry Tang
Keyword(s):  
Shear Viscosity ◽  
Amorphous Polymers ◽  
Simple Expression ◽  
Crossover Frequency ◽  
Crossover Point ◽  
Zero Shear Viscosity ◽  
Plateau Modulus ◽  
Good Agreement

Abstract Based upon the Doi-Edwards theory, a simple expression has been obtained for zero-shear viscosity in terms of the plateau modulus and the crossover frequency. There are no adjustable parameters in the expression. The model is in very good agreement with the zero-shear viscosity values for linear polybutadienes, the typical discrepancy being ∼5–10%. If the model can be validated for other linear amorphous polymers, it may become possible to estimate the zero-shear viscosity by measuring a single Theological parameter (the crossover frequency).

Estimation of the Thermodynamic Properties of Branched Hydrocarbons

2000 ◽  
Vol 122 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Hui He ◽  
Mohamad Metghalchi ◽  
James C. Keck
Keyword(s):  
Thermodynamic Properties ◽  
Degrees Of Freedom ◽  
Statistical Thermodynamic ◽  
Motion Modes ◽  
Branched Alkanes ◽  
Branched Hydrocarbons ◽  
Wide Range ◽  
On Line ◽  
Kinetic Calculations ◽  
Good Agreement

A simple model has been developed to estimate the sensible thermodynamic properties such as Gibbs free energy, enthalpy, heat capacity, and entropy of hydrocarbons over a wide range of temperatures with special attention to the branched molecules. The model is based on statistical thermodynamic expressions incorporating translational, rotational and vibrational motions of the atoms. A method to determine the number of degrees of freedom for different motion modes (bending and torsion) has been established. Branched rotational groups, such as CH3 and OH, have been considered. A modification of the characteristic temperatures for different motion mode has been made which improves the agreement with the exact values for simple cases. The properties of branched alkanes up to 2,3,4,-trimthylpentane have been calculated and the results are in good agreement with the experimental data. A relatively small number of parameters are needed in this model to estimate the sensible thermodynamic properties of a wide range of species. The model may also be used to estimate the properties of molecules and their isomers, which have not been measured, and is simple enough to be easily programmed as a subroutine for on-line kinetic calculations. [S0195-0738(00)00902-X]

Laser-Ultrasonics as a Technique to Study Recrystallisation and Grain Growth

2004 ◽  
Vol 467-470 ◽  
pp. 1353-1362 ◽  
Author(s):  
Eva Lindh-Ulmgren ◽  
Mattias Ericsson ◽  
Dorota Artymowicz ◽  
W. Bevis Hutchinson
Keyword(s):  
Carbon Steels ◽  
Laser Ultrasonics ◽  
Continuous Annealing ◽  
Low Carbon ◽  
Steel Sheets ◽  
On Line ◽  
Cold Rolled ◽  
Dynamic Heating ◽  
Good Agreement

Laser-Ultrasonics (LUS) provides a means of obtaining microstructure information continuously and non-destructively both in the laboratory and for quality control on-line in industry. Ultrasound is both generated and recorded using lasers which permits remote, non-contact operation with fast sampling and also the capability of working at high temperatures or at moving surfaces, for example during industrial continuous annealing. Examples of dynamic heating trials will be presented for samples of cold rolled steel sheets where primary recrystallisation and ferrite austenite transformation are monitored in-situ as a function of temperature. Examples are also presented where the grain size of low carbon steels have been quantitatively analysed and show very good agreement with microscopy methods.

Analysis and Validation of Cutting Forces Prediction Models in Micromachining

2006 ◽  
Vol 526 ◽  
pp. 13-18 ◽  
Author(s):  
H. Perez ◽  
Antonio Vizan Idoipe ◽  
J. Perez ◽  
J. Labarga
Keyword(s):  
Experimental Data ◽  
Cutting Force ◽  
Cutting Forces ◽  
Prediction Models ◽  
Precision Machining ◽  
New Model ◽  
Proposed Model ◽  
On Line ◽  
Machine Control ◽  
Good Agreement

Many investigations have been developed related to precision machining with features in the millimetre scale. In this paper different cutting force models for micromilling are analyzed and compared. A new model based on specific cutting force that also considers run-out errors has been developed. The estimated cutting forces obtained with this model had good agreement with the experimental data. Also, the proposed model allows to be implemented within the machine control for the on-line optimization of the micromilling process.

Model of a Combined Cycle Steam Section for Use in an On-Line Fuzzy-Based Diagnosis System

2012 ◽  
Author(s):  
Rafael Barbosa ◽  
Sandro Ferreira ◽  
Raphael Duarte ◽  
Paula Ribeiro Pinto ◽  
Marília Paula e Silva
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Computer Models ◽  
Combined Cycle ◽  
Feed Water ◽  
Diagnosis System ◽  
Power Plant Equipment ◽  
Partial Load ◽  
On Line ◽  
Good Agreement

In recent years, combined cycle power plants showed remarkable progress in the safe operation and reliability of their equipment, mostly because of the reliable control and instrumentation systems available today. However, these systems cannot detect and evaluate inconsistencies in the behaviour of equipment due to failures and avoid trips caused by catastrophic events. Computer models developed to simulate the power plant equipment are often employed in diagnosis tools in order to provide accurate healthy parameters that are compared to the field measured parameters. In this work, the computer models built for the simulation of some of the main bottoming cycle equipment of a real power plant (steam turbine, HRSG, boiler feed water pumps and condenser) are described. These models were developed through characteristics maps and constitutive equations related to the fluid path analysis, implemented in Fortran language. The results provided by the developed models for each equipment show good agreement with operational data at base and partial load in simulations that covered a good part of the load domain. Due to the good agreement between the measured parameters values and those calculated through simulation, these models are intended to be included in an on-line fuzzy-based diagnosis system.

THEORETICAL PREDICTION OF DEBYE TEMPERATURE FOR MANTLE MINERALS AT HIGH TEMPERATURES

2011 ◽  
Vol 25 (12) ◽  
pp. 1593-1600 ◽  
Author(s):  
ANJANI K. PANDEY ◽  
ABHAY P. SRIVASTAVA
Keyword(s):  
Shear Modulus ◽  
Elastic Properties ◽  
Laboratory Data ◽  
Seismic Velocities ◽  
Mantle Minerals ◽  
Seismic Properties ◽  
Debye Temperatures ◽  
Temperature Ranges ◽  
Experimental Values ◽  
Good Agreement

The seismic properties of a material depend on composition, crystal structure, temperature, pressure and in some cases defect concentrations. Most of the earth is made up of crystals. The elastic properties of crystals depend on orientation and frequency. Thus, the interpretation of seismic data or the extrapolation of laboratory data requires knowledge of crystal or mineral physics, elasticity and thermodynamics. In the present work, we calculated the shear modulus, seismic velocities and Debye temperatures at different high temperature ranges. The temperature dependence of elastic properties such as shear modulus, seismic velocities and Debye temperatures has been measured using Hill's averaging method and other thermodynamic methods for five silicate mantle minerals viz. MgAl 2 O 4, Mg 2 SiO 4, Fe 2 SiO 4, Mn 2 SiO 4, and Co 2 SiO 4. The results are found to be in good agreement with experimental values.

scholarly journals Inlet and Exit-Header Shapes for Uniform Flow Through a Resistance Parallel to the Main Stream

1961 ◽  
Vol 83 (3) ◽  
pp. 361-368 ◽  
Author(s):  
Morris Perlmutter
Keyword(s):  
Experimental Study ◽  
Pressure Drop ◽  
Total Pressure ◽  
Experimental Results ◽  
Main Stream ◽  
Height Ratio ◽  
Large Length ◽  
Flow Through ◽  
Pass Through ◽  
Good Agreement

An analytical and experimental study of flow in headers with a resistance parallel to the turbulent and incompressible main stream has been made. The purpose was to shape the inlet and exit headers, which had a large length-to-height ratio, so that the fluid would pass through the resistance uniformly. Analytical wall shapes and estimated total pressure drop through the headers were compared with experimental results. Good agreement between analysis and experiment was found for the cases compared.

Sensor Characteristics of Carbon Fiber Mat

2006 ◽  
Vol 326-328 ◽  
pp. 1451-1454 ◽  
Author(s):  
Xiao Yu Zhang ◽  
Zhuo Qiu Li ◽  
Xian Hui Song ◽  
Yong Lv
Keyword(s):  
Carbon Fiber ◽  
Concrete Structure ◽  
Fiber Reinforced Concrete ◽  
Static Characteristics ◽  
Gage Factor ◽  
Thin Carbon ◽  
On Line ◽  
New Type ◽  
New Skin ◽  
Good Agreement

Structural health monitoring (SHM) is becoming a popular topic. Carbon fiber reinforced concrete (CFRC) is an intrinsically smart material that can sense strain. The resistivity increases reversibly under tension and decreases under compression. A new skin-like sensor —cement-based smart layer had been put forward, which can serve as whole field strain sensor. The smart layer is satisfactorily consistent with concrete structure. The smart layer is a thin carbon fiber mat cementbased composite material layer with finite electrodes. It can cover the surface of concrete structure, and provide on-line reliable information about the deformation of whole concrete structure. The static characteristics of the new-type sensor had been researched. Its gage factor is 20-25 under tension and 25-30 under compression within the elastic deformation range. Furthermore the smart layer has satisfactory linearity and repeatability. In this paper, the sensor characteristics of the bare carbon fiber mat have been reached. The resistivity of carbon fiber mat has good agreement with strain under uniaxial tension. The gage factor can be up to 375, and the sensor limit can be up to 10000 microstrain. The strain and the fractional change in electrical resistance .R/R0 are totally reversible and reproducible under cyclic loading and amplitude-variable cyclic tensile loading.

scholarly journals A Factor-Graph-Based Approach to Vehicle Sideslip Angle Estimation

Sensors ◽  
2021 ◽  
Vol 21 (16) ◽  
pp. 5409
Author(s):  
Antonio Leanza ◽  
Giulio Reina ◽  
José-Luis Blanco-Claraco
Keyword(s):  
Graphical Model ◽  
Important Variable ◽  
Factor Graph ◽  
Mathematical Framework ◽  
Sideslip Angle ◽  
The Family ◽  
On Line ◽  
Offline Processing ◽  
Proprioceptive Sensors ◽  
Good Agreement

Sideslip angle is an important variable for understanding and monitoring vehicle dynamics, but there is currently no inexpensive method for its direct measurement. Therefore, it is typically estimated from proprioceptive sensors onboard using filtering methods from the family of the Kalman filter. As a novel alternative, this work proposes modeling the problem directly as a graphical model (factor graph), which can then be optimized using a variety of methods, such as whole-dataset batch optimization for offline processing or fixed-lag smoothing for on-line operation. Experimental results on real vehicle datasets validate the proposal, demonstrating a good agreement between estimated and actual sideslip angle, showing similar performance to state-of-the-art methods but with a greater potential for future extensions due to the more flexible mathematical framework. An open-source implementation of the proposed framework has been made available online.

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