Determination of Polyolefins Powder Flow Characteristics in a Purge Column during Product Transitions

2007 ◽  
Vol 46 (24) ◽  
pp. 8120-8129
Author(s):  
Alberto Buchelli ◽  
Jeffrey R. Golden ◽  
Debra L. Beran
Keyword(s):  
Flow Characteristics ◽  
Powder Flow

scholarly journals Determination of the cohesion, powder flow speed dependency and caking tendency of cocoa powders

2019 ◽  
Vol 2 (3) ◽  
pp. 483-491
Author(s):  
Mahmut Dogan ◽  
Duygu Aslan Türker
Keyword(s):  
Flow Characteristics ◽  
Fat Content ◽  
Flow Speed ◽  
Solid Particles ◽  
Powder Flow ◽  
Food Powders ◽  
Three Samples ◽  
Powder Flowability ◽  
The Mean

Cocoa is one of the most popular foodstuffs known for centuries and cocoa powders are particularly exposed to caking, a phenomenon of agglomeration of solid particles that disrupt powder functionality. This study aimed to identify the main powder flow characteristics such as caking, cohesion and powder flow speed dependency of cocoa powders, according to their fat content. The loose and tapped bulk density, as well as Carr ratio of cocoa powders, was determined as bulking properties for comparing and interpreting the flowability. The caking was observed in all three samples. With increasing fat content, a decrease in the powder flowability was detected. The mean cake strength of the low fat, reduced fat and full-fat cocoa powders was recorded as 110.42±1.71; 164.175±1.75 and 207.96±0.93, respectively. These results suggest that the fat contents of the food powders may be a useful parameter to describe the powder flowability.

Determination of Flow Characteristics and Turbulent Heat Transfer in a Ribbed Roughened Square Duct, Part 2: Numerical Simulations

2011 ◽  
Vol 110-116 ◽  
pp. 2364-2369
Author(s):  
Amin Etminan ◽  
H. Jafarizadeh ◽  
M. Moosavi ◽  
K. Akramian
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Flow Characteristics ◽  
Turbulence Models ◽  
Turbulent Heat Transfer ◽  
Turbulent Heat ◽  
Square Duct ◽  
Optimized Model ◽  
Rsm Model

In the part 1 of this research, some useful turbulence models presented. In that part advantages of those turbulence models has been gathered. In the next, numerical details and procedure of solution are presented in details. By use of different turbulence models, it has been found that Spallart-Allmaras predicted the lowest value of heat transfer coefficient; in contrast, RSM1 has projected the more considerable results compared with other models; besides, it has been proven that the two-equation models prominently taken lesser time than RSM model. Eventually, the RNG2 model has been introduced as the optimized model of this research; moreover.

Experimental and Numerical Analysis of the Powder Flow in a Multi-Channel Coaxial Nozzle of a Direct Metal Deposition System

2021 ◽  
Vol 143 (7) ◽  
Author(s):  
Piyush Pant ◽  
Dipankar Chatterjee ◽  
Sudip Kumar Samanta ◽  
Aditya Kumar Lohar
Keyword(s):  
Gas Flow ◽  
Flow Characteristics ◽  
Turbulence Models ◽  
Deposition Process ◽  
Metal Deposition ◽  
Direct Metal Deposition ◽  
Powder Flow ◽  
Coaxial Nozzle ◽  
Proposed Model ◽  
Blown Powder

Abstract The work explores the powder transport process, using numerical simulation to address the dynamics of the powder flow in an in-house built multi-channel coaxial nozzle of a direct metal deposition (DMD) system. The fluid turbulence is handled by the standard k–ɛ and k–ω turbulence models, and the results are compared in order to predict their suitability. An image-based technique using CMOS camera is adopted to determine the powder flow characteristics. The model is validated with the in-house experimental results and verified available results in the literature. The findings of this work confirms the application of the k–ω model for powder gas flow investigations in blown powder additive manufacturing (AM) processes due to its better predictive capability. The proposed model will assist in simulating the direct metal deposition process.

Experimental Verification of the Improvements Achieved by a New LP-Blade Design in a Steam Turbine

1992 ◽  
Author(s):  
H. Stetter ◽  
G. Eyb ◽  
C. Zimmermann ◽  
H.-G. Hosenfeld
Keyword(s):  
Steam Turbine ◽  
Entire Range ◽  
Flow Characteristics ◽  
Radial Pressure ◽  
Blade Design ◽  
Steam Turbines ◽  
Guide Vanes ◽  
Last Stage ◽  
The University

In order to verify the improvements in the understanding of the flow in turbomachinery, extensive investigations were carried out at the LP-steam turbine at the University of Stuttgart. This paper initially focuses on the specific measuring technique in steam turbines with respect to problems of condensation. The stator wakes, noticeable in all measuring planes of the stage, require the determination of the flow vector over a large portion of the cross-section to obtain representative values. The application of a newly designed last stage for LP-steam turbines, which is characterized by curved guide-vanes, led to considerable improvements of the flow over the entire range of operation. The results gained by measurements on that stage are compared to former measurements on a stage version with straight guide-vanes. A significant change of flow characteristics over the blade span can be noticed. Particularly, the flow in the hub region was improved by balancing the radial pressure distribution.

Determination of Subsurface Flow Characteristics for the Installation of Groundwater Samplers

2015 ◽  
pp. 383-393 ◽  
Author(s):  
Wayne P. Dulaney ◽  
T. J. Gish ◽  
C. S. T. Daughtry ◽  
J. A. Doolittle ◽  
P. T. Miller ◽  
...  
Keyword(s):  
Subsurface Flow ◽  
Flow Characteristics

scholarly journals Theoretical Rotordynamic Coefficients of Labyrinth Gas Seals: a Parametric Study on a Bulk Model

1999 ◽  
Vol 5 (1) ◽  
pp. 67-76 ◽  
Author(s):  
Paola Forte ◽  
Fabio Latini
Keyword(s):  
Flow Characteristics ◽  
Perturbation Approach ◽  
Rotordynamic Coefficients ◽  
Volume Model ◽  
Complex Models ◽  
Gas Seals ◽  
Bulk Model ◽  
Stiffness And Damping ◽  
Good Agreement

To date, available mathematical bulk models for the determination of linearized rotordynamic coefficients of labyrinth gas seals yield results which are not always in good agreement with the experimental ones. The object of this work is to discuss the limits of these models and to point out possible improvements and aspects that need further investigation.After a study of the steady flow characteristics with an FEM code, a parametric computer program, based on a known two-volume model, has been developed. A perturbation approach has been applied to the governing equations of the bulk model to calculate the stiffness and damping coefficients. Predicted coefficients are compared to the results of an earlier one-volume model.The model has also been tested with different expressions of the axial velocities in the two volumes and different laws for leakage and shear stress. The theoretical results are compared to the published experimental ones, pointing out the small effect of the various parameters in improving the correlation and the need of more complex models.

Sign in / Sign up

Export Citation Format

Share Document