Fixing a Boiler with CFD

1998 ◽  
Vol 120 (04) ◽  
pp. 59-61
Author(s):  
Kevin Parker
Keyword(s):  
Three Dimensional ◽  
Paper Mill ◽  
Operating Conditions ◽  
Clear Understanding ◽  
Post Processing ◽  
Processing Program ◽  
Hidden Line ◽  
Computational Fluid Dynamics Cfd ◽  
Animated Sequence ◽  
Light Shading

This article focuses on carryover at a paper mill that had been solved using computational fluid dynamics (CFD) to visualize flow within the boiler. Technicians had tried adjusting airflow and firing arrangements without success. They turned the problem over to analysts who simulated the airflow within the boiler using CFD. An animated sequence of streamlines showing airflow provided engineers with a clear understanding of exactly what was happening inside the boiler, making it relatively easy to adjust operating conditions and solve the problem. McDermott analysts use FIELDVIEW, a commercial post-processing program from Intelligent Light in Lyndhurst, NJ. With the software, the analyst can create three-dimensional perspective views with hidden-line removal and light shading. She or He can trace the path of a marker traveling along with the fluid through a series of animated views. The analysts made a second FIELDVIEW movie of the airflow conditions with the new arrangement, showing the elimination of the center core. They played the two movies simultaneously on two monitors set side-by-side to demonstrate for the customer’s engineers how the recommended changes would solve the problem.

CFD Analysis of Batch-Type Reheating Furnace

2007 ◽  
Author(s):  
Bin Wu ◽  
Andrew M. Arnold ◽  
Eugene Arnold ◽  
George Downey ◽  
Chenn Q. Zhou
Keyword(s):  
Three Dimensional ◽  
Furnace Operation ◽  
Operating Conditions ◽  
Temperature Fields ◽  
Cfd Analysis ◽  
Reheating Furnace ◽  
Batch Type ◽  
Billet Quality ◽  
Actual Operating ◽  
Computational Fluid Dynamics Cfd

In the steelmaking industry, reheating furnaces are used to heat the billets or blooms to the rolling temperature; the uniformity of the temperature in the furnace determines billet quality. In order to obtain a better understanding of the furnace operation, which influences the temperature distribution; Computational Fluid Dynamics (CFD) analysis is conducted to examine the transient and three dimensional temperature fields in a reheating furnace using the commercial software Fluent®. A number of actual operating conditions, based on the ArcelorMittal Steelton No.3 reheating furnace, are computed. The numerical results are used to optimize the operating parameters and thus help to improve the steel quality.

Prediction of Raceways in a Blast Furnace

2006 ◽  
Author(s):  
Naresh K. Selvarasu ◽  
D. Huang ◽  
Zumao Chen ◽  
Mingyan Gu ◽  
Yongfu Zhao ◽  
...  
Keyword(s):  
Particle Size ◽  
Blast Furnace ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Gas Oil ◽  
Cfd Model ◽  
Coke Particle ◽  
Fuel Gas ◽  
Computational Fluid Dynamics Cfd ◽  
Insight Into

In a blast furnace, preheated air and fuel (gas, oil or pulverized coal) are often injected into the lower part of the furnace through tuyeres, forming a raceway in which the injected fuel and some of the coke descending from the top of the furnace are combusted and gasified. The shape and size of the raceway greatly affect the combustion of, the coke and the injected fuel in the blast furnace. In this paper, a three-dimensional (3-D) computational fluid dynamics (CFD) model is developed to investigate the raceway evolution. The furnace geometry and operating conditions are based on the Mittal Steel IH7 blast furnace. The effects of Tuyere-velocity, coke particle size and burden properties are computed. It is found that the raceway depth increases with an increase in the tuyere velocity and a decrease in the coke particle size in the active coke zone. The CFD results are validated using experimental correlations and actual observations. The computational results provide useful insight into the raceway formation and the factors that influence its size and shape.

General Post Processing Program for J-Integral Calculation around Arbitrary Shaped Cracks

2008 ◽  
Vol 33-37 ◽  
pp. 827-832
Author(s):  
Yasuhiro Kanto
Keyword(s):  
Stress Analysis ◽  
Numerical Integration ◽  
Three Dimensional ◽  
Discrete Data ◽  
J Integral ◽  
Post Processing ◽  
Processing Program ◽  
Analysis Models ◽  
Stress Analyses

In this paper, a general post processing program for J-integral calculation is developed to apply to arbitrary shaped cracks in a three dimensional body. Usually J-integral calculation programs are options for specific stress analysis programs and they are not applicable to results from different analysis programs. In most cases, there are many limitations in analysis models or shapes of cracks. This situation is not favorable for users. This paper will demonstrate a development of a post-processing program to calculate J-integral for arbitrary shaped cracks in a three dimensional body. This program requires only discrete data of displacements and stresses at nodal or numerical integration points. Users can use their own programs for stress analyses and calculate J-integral after that. In this paper, errors in approximation will be discussed as the first stage of the development.

Modelling of the Membrane Permeability Effect on the H2 Production Using CFD Method

2014 ◽  
Vol 12 (1) ◽  
pp. 333-344 ◽  
Author(s):  
Yacine Benguerba ◽  
Christine Dumas ◽  
Barbara Ernst
Keyword(s):  
Three Dimensional ◽  
Porous Membrane ◽  
H2 Production ◽  
Operating Conditions ◽  
Membrane Reactors ◽  
Production Of Hydrogen ◽  
Different Temperatures ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Method ◽  
Supported Ni

Abstract Autothermal reforming of CH4 in a membrane catalytic microreactor for the production of hydrogen at different temperatures over supported Ni catalysts has been studied. A three-dimensional mathematical model was developed using a computational fluid dynamics (CFD) technique. The effect of using different membranes on the performance of the micro-reactor was analysed. The amounts of hydrogen produced and separated in each case, under the same operating conditions, were compared. It was proven that using the porous membrane (Ni–Al2O3) could be an economic solution for the production and separation of hydrogen in membrane reactors.

Centrifugal Compressor Aero-Mechanical Design: A Machine Learning Approach

2021 ◽  
Author(s):  
Dario Barsi ◽  
Andrea Perrone ◽  
Luca Ratto ◽  
Gianluca Ricci ◽  
Marco Sanguineti
Keyword(s):  
Machine Learning ◽  
Surrogate Model ◽  
Mechanical Design ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Model Parameters ◽  
Design And Optimization ◽  
Machine Learning Approach ◽  
Computational Fluid Dynamics Cfd ◽  
Geometry Parameterization

Abstract The present paper presents an enhanced method for multi-disciplinary design and optimization of centrifugal compressors based on Machine Learning (ML) algorithms. The typical approach involves the preliminary design, the geometry parameterization, the generation of aero-mechanical databases and a surrogate-model based optimization. This procedure is able to provide excellent results, but it is time consuming and has to be repeated for each new design. The aim of the proposed procedure is to actively exploit the simulations performed in the past for subsequent designs thanks to the predictive capabilities of the ML surrogate model. A commercial 3D (three dimensional) computational fluid dynamics (CFD) solver for the aerodynamic computations and a commercial finite element code for the mechanical integrity calculations, coupled with scripting modules, have been adopted. Two different compressors, with different geometry and operating conditions, have been designed and two aero-mechanical databases have been developed. Then, these two databases have been joined and have been used for the training and validation of the surrogate model. To assess the performance of this approach, two new compressors have been designed, case 1 with operating conditions between those of the databases used for training and validation and case 2 with operating conditions far above. The use of an optimizer coupled to the prediction of the surrogate model has enabled to define the “best set” of model parameters, in compliance with aero-mechanical objectives and constraints. The accuracy of the ML algorithm forecast has been evaluated through CFD and FEM simulations carried out iteratively on the optimal samples, with new simulations added to the database for further training of the surrogate model. The results have been presented with reference to cases 1 and 2 and highlight all the benefits of the proposed approach.

Transonic fan and compressor design

1999 ◽  
Vol 213 (5) ◽  
pp. 419-436 ◽  
Author(s):  
W. J. Calvert ◽  
R. B. Ginder
Keyword(s):  
Three Dimensional ◽  
Operating Conditions ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Specific Flow ◽  
Transonic Compressor ◽  
Compressor Design ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Analyses ◽  
Transonic Fan

Transonic fans and compressors are now widely used in gas turbine engines because of their benefits in terms of compactness and reduced weight and cost. However, careful and precise design is essential if high levels of performance are to be achieved. In this paper, the evolution of transonic compressor designs and methods is outlined, followed by more detailed descriptions of current compressor configurations and requirements and modern aerodynamic design methods and philosophies. Current procedures employ a range of methods to allow the designer to refine a new design progressively. Overall parameters, such as specific flow and mean stage loading, the axial matching between the stages at key operating conditions and the radial matching between the blade rows are set in turn, using one- and two-dimensional techniques. Finally, detailed quasi-three-dimensional and three-dimensional computational fluid dynamics (CFD) analyses are employed to refine the design. However, it is important to appreciate that the methods all have significant limitations and designers must take this into account if successful compressors are to be produced.

scholarly journals Numerical Research of Pump-as-Turbine Performance with Synergy Analysis

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1031
Author(s):  
Zheng Cao ◽  
Jianqiang Deng ◽  
Linkun Zhao ◽  
Lin Lu
Keyword(s):  
Flow Rate ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Leading Edge ◽  
Operating Conditions ◽  
Field Analysis ◽  
Sensitivity Index ◽  
Computational Fluid Dynamics Cfd ◽  
Numerical Research ◽  
Hydraulic Devices

The wide use of pumps and turbines has significant value in energy conservation and utilization. In this work, a three-dimensional Computational Fluid Dynamics (CFD) model and a one-dimensional theoretical model of a Pump as Turbine (PAT) were established. On this basis, the correlation between pressure and velocity was quantitatively investigated by a proposed sensitivity index (SPV). A synergy field analysis was then applied to evaluate the flow characteristics of a pump and PAT, providing a perspective from the mechanism of the energy transfer enhancement for hydraulic devices. Moreover, the hydraulic and synergy performances of PAT were studied under various operating conditions. The results show that the minimum SPV is obtained in the impeller. With increasing flow rate, the SPV of the PAT generally increases, and the synergy angle of the impeller surface increases as well. A strong disordered synergy field is observed in regions of the blade leading edge, trailing edge, and volute tongue. The variations in efficiency and head with flow rate showed similar trends, respectively, with the synergy angle of the outlet and the mid-plane. This study provides an analytical method for quantitative evaluation of flow synergy characteristics, and it supplies a basis for further design improvement of the pump and PAT.

Application of a Pilot-Scale Pulsed Electrocoagulation system to OCC-Based Paper Mill Effluent

TAPPI Journal ◽  
2009 ◽  
Vol 8 (3) ◽  
pp. 14-20 ◽  
Author(s):  
YUAN-SHING PERNG ◽  
EUGENE I-CHEN WANG ◽  
SHIH-TSUNG YU ◽  
AN-YI CHANG
Keyword(s):  
Water Quality ◽  
Quality Indicators ◽  
Paper Mill ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Optimal Dosage ◽  
Water Quality Indicators ◽  
Paper Mill Effluent ◽  
Treated Effluent ◽  
True Color

Trends toward closure of white water recirculation loops in papermaking often lead to a need for system modifications. We conducted a pilot-scale study using pulsed electrocoagulation technology to treat the effluent of an old corrugated containerboard (OCC)-based paper mill in order to evaluate its treatment performance. The operating variables were a current density of 0–240 A/m2, a hydraulic retention time (HRT) of 8–16 min, and a coagulant (anionic polyacrylamide) dosage of 0–22 mg/L. Water quality indicators investigated were electrical con-ductivity, suspended solids (SS), chemical oxygen demand (COD), and true color. The results were encouraging. Under the operating conditions without coagulant addition, the highest removals for conductivity, SS, COD, and true color were 39.8%, 85.7%, 70.5%, and 97.1%, respectively (with an HRT of 16 min). The use of a coagulant enhanced the removal of both conductivity and COD. With an optimal dosage of 20 mg/L and a shortened HRT of 10 min, the highest removal achieved for the four water quality indicators were 37.7%, 88.7%, 74.2%, and 91.7%, respectively. The water qualities thus attained should be adequate to allow reuse of a substantial portion of the treated effluent as process water makeup in papermaking.

Effect of post‐processing treatments on the quality of three‐dimensional printed rice starch constructs

2021 ◽  
Author(s):  
Radhika Theagarajan ◽  
Shubham Nimbkar ◽  
Jeyan Arthur Moses ◽  
Chinnaswamy Anandharamakrishnan
Keyword(s):  
Three Dimensional ◽  
Rice Starch ◽  
Post Processing

scholarly journals On the Post-Processing of 3D-Printed ABS Parts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1559
Author(s):  
Mohammad Reza Khosravani ◽  
Jonas Schüürmann ◽  
Filippo Berto ◽  
Tamara Reinicke
Keyword(s):  
Surface Treatment ◽  
Fused Deposition Modeling ◽  
Three Dimensional ◽  
Acrylonitrile Butadiene Styrene ◽  
Experimental Tests ◽  
Fracture Load ◽  
Post Processing ◽  
Fused Deposition ◽  
Dog Bone ◽  
3D Printed

Application of Additive Manufacturing (AM) has significantly increased in the past few years. AM also known as three-dimensional (3D) printing has been currently used in fabrication of prototypes and end-use products. Considering the new applications of additively manufactured components, it is necessary to study structural details of these parts. In the current study, influence of a post-processing on the mechanical properties of 3D-printed parts has been investigated. To this aim, Acrylonitrile Butadiene Styrene (ABS) material was used to produce test coupons based on the Fused Deposition Modeling (FDM) process. More in deep, a device was designed and fabricated to fix imperfection and provide smooth surfaces on the 3D-printed ABS specimens. Later, original and treated specimens were subjected to a series of tensile loads, three-point bending tests, and water absorption tests. The experimental tests indicated fracture load in untreated dog-bone shaped specimen was 2026.1 N which was decreased to 1951.7 N after surface treatment. Moreover, the performed surface treatment was lead and decrease in tensile strength from 29.37 MPa to 26.25 MPa. Comparison of the results confirmed effects of the surface modification on the fracture toughness of the examined semi-circular bending components. Moreover, a 3D laser microscope was used for visual investigation of the specimens. The documented results are beneficial for next designs and optimization of finishing processes.

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