Performance Modification of an Erosion-Damaged Large-Sized Centrifugal Fan

2021 ◽  
Author(s):  
Nicola Aldi ◽  
Nicola Casari ◽  
Michele Pinelli ◽  
Alessio Suman ◽  
Alessandro Vulpio ◽  
...  
Keyword(s):  
Structural Damage ◽  
Structural Integrity ◽  
Internal Flow ◽  
Centrifugal Fan ◽  
Erosion Process ◽  
Planning And Scheduling ◽  
Simulation Based ◽  
Unbalanced Load ◽  
Impact Characteristics ◽  
Clinker Production

Abstract Heavy-duty fans are frequently employed in industrial processes that involve the operation of contaminated gases. Particle-laden flows may cause erosion issues, generating several drawbacks such as unbalanced load, vibrations and structural damage responsible for performance degradation and early failure. In this paper, the erosion behavior of a large-sized centrifugal fan employed in clinker production is studied by numerical simulation. Based on preliminary numerical results for the undamaged fan configuration and on-field erosion detections, the geometry damage effects due to the erosion process are analyzed. The severe erosive conditions under which these machines operate determine a progressive reduction in wall thickness of specific fan zones, which may finally result in the formation of holes. This, in turn, makes the internal flow field changing, affecting contaminant trajectories and impact characteristics. CFD predictions show that erosion-induced damage on the fan inlet cone causes a distortion of the velocity profile immediately upstream of the impeller, which influences the impeller flow. Simultaneously, the erosion process changes, leading to a modification of particle impact areas, impact kinematic characteristics and erosion intensity. This investigation focuses on the importance of erosion predictions for maintenance planning and scheduling and demonstrates how localized damage could be responsible for larger damage, involving the structural integrity of the installation.

Analysis and Evaluation of Wind Turbine Flow Field and Noise Simulation Based on CFD Software

2014 ◽  
Vol 716-717 ◽  
pp. 755-759
Author(s):  
Ling Xiao Weng ◽  
Jiu Nan Xu ◽  
Zhi Xin Hu
Keyword(s):  
Flow Field ◽  
Wind Turbine ◽  
Optimization Design ◽  
Power Level ◽  
Internal Noise ◽  
Internal Flow ◽  
Fluid Simulation ◽  
Centrifugal Fan ◽  
Two Dimensional ◽  
Simulation Based

CFD is the abbreviation of the computational fluid dynamics, which is widely used in engineering fluid simulation. Based on two-dimensional N-S equation and k-e turbulence model, this paper uses FLUENT software, finite volume method and SIMPLEC algorithm to do numerical simulation and analysis on flow field in centrifugal fan. In order to improve the efficiency and accuracy of calculation, this paper uses AutoCAD to establish the two-dimensional model of fan, and uses the structured triangular mesh to divide grid. Encrypting the blade can improve the precision and also save the computer memory. Through the calculation we get the internal flow field velocity and pressure distribution in the wind turbine, and get the power level cloud of internal noise in fan. It provides the technical reference for the optimization design of wind turbine.

scholarly journals Integrity Management of Marine Structures; With Emphasis on Design for Structural Robustness

2018 ◽  
Author(s):  
Torgeir Moan
Keyword(s):  
Structural Damage ◽  
Structural Integrity ◽  
Oil And Gas ◽  
Offshore Structures ◽  
Design Standards ◽  
Limit States ◽  
Fabrication Errors ◽  
Integrity Management ◽  
Operational Errors ◽  
And Control

Based on relevant accident experiences with oil and gas platforms, a brief overview of structural integrity management of offshore structures is given; including an account of adequate design criteria, inspection, repair and maintenance as well as quality assurance and control of the engineering processes. The focus is on developing research based design standards for Accidental Collapse Limit States to ensure robustness or damage tolerance in view damage caused by accidental loads due to operational errors and to some extent abnormal structural damage due to fabrication errors. Moreover, it is suggested to provide robustness in cases where the structural performance is sensitive to uncertain parameters. The use of risk assessment to aid decisions in lieu of uncertainties affecting the performance of novel and existing offshore structures, is briefly addressed.

Design and Validation of a Simulation-Based Modular Planning and Scheduling System of Semiconductor Fabrication Facilities

2011 ◽  
Vol 48-49 ◽  
pp. 378-381
Author(s):  
Li Li ◽  
Fei Qiao
Keyword(s):  
Simulation Modeling ◽  
General Structure ◽  
Structure Model ◽  
Planning And Scheduling ◽  
Scheduling System ◽  
Information Layer ◽  
Simulation Based ◽  
Semiconductor Fabrication ◽  
Control Modules

A simulation-based modular planning and scheduling system developed for semiconductor fabrication facilities (SFFs) is discussed. Firstly, the general structure model (GSM) for SFFs, composed of a configurable definition layer, a physical layer, a process information layer and a planning and scheduling layer, is proposed. Secondly, a data-based dynamic simulation modeling method is given. Thirdly, a simulation-based modular planning and scheduling system (SMPSS) for SFFs, including model modules, release control modules, scheduling modules and rescheduling modules, is designed and developed. Finally, a case study is used to demonstrate the effectiveness of

scholarly journals Structural Damage Diagnosis and Prediction Using Machine Learning and Deep Learning Models: Comprehensive Review of Advances

2019 ◽  
Author(s):  
Amir Mosavi
Keyword(s):  
Machine Learning ◽  
Composite Structures ◽  
Structural Damage ◽  
Structural Integrity ◽  
State Of The Art ◽  
Future Trends ◽  
Learning Models ◽  
Damage Diagnosis ◽  
Comprehensive Review ◽  
Initiation And Propagation

The loss of integrity and adverse effect on mechanical properties can be concluded as attributing miro/macro-mechanics damage in structures, especially in composite structures. Damage as a progressive degradation of material continuity in engineering predictions for any aspects of initiation and propagation requires to be identified by a trustworthy mechanism to guarantee the safety of structures. Besides the materials design, structural integrity and health are usually prone to be monitored clearly. One of the most powerful methods for the detection of damage is machine learning (ML). This paper presents the state of the art of ML methods and their applications in structural damage and prediction. Popular ML methods are identified and the performance and future trends are discussed.

Influences of Splitter Blades on the Centrifugal Fan Performances

1989 ◽  
Author(s):  
Lichuan Gui ◽  
Chuangang Gu ◽  
Hongshou Chang
Keyword(s):  
Solution Method ◽  
Pressure Coefficient ◽  
Internal Flow ◽  
Experimental Result ◽  
Centrifugal Fan ◽  
Fan Performance ◽  
Load Distributions ◽  
Result Show ◽  
Engineering Practices ◽  
Approximate Solution Method

Centrifugal fan and compressors with splitter blades are widely utilized in engineering practices. A detail investigation of the influences of splitter blades on a forward-curved centrifugal fan performances is presented in the paper. The study includes two parts: experiment and numerical calculation. The experiments were produced in a specific impeller with adjustable splitter blades in order to get the performances in different conditions. The internal flow field in the impeller was calculated by means of FEASM (Finite Element Approximate Solution Method, Gu, 1984). The experimental result show that changing the circumferential positions of the splitter blades has a noticeble influence on the fan performance, the incidence of splitter blades also has a certain effect on it, and properly lengthened splitter blades can raise the total pressure coefficient. The velocity and load distributions on the blade surfaces calculated can be used to analyse the phenomena above satisfactorily.

scholarly journals Assessment of traffic-induced vibrations of Ozanam Building of Adamson University

2018 ◽  
Vol 169 ◽  
pp. 01042
Author(s):  
Earl Shadd D. Araña, ◽  
Leira Liz A. Bisain ◽  
Rae Cecil N. Acedera ◽  
John Elmer C. Guillermo ◽  
Albert A. Griño
Keyword(s):  
Particle Velocity ◽  
Structural Damage ◽  
Structural Integrity ◽  
Preventive Measures ◽  
Threshold Value ◽  
Structural Members ◽  
Heavy Vehicles ◽  
Maximum Peak ◽  
Main Factors

Vibration is one of the main factors for fatigue in structures which can cause damages such as cracks and in critical cases could result to collapse. Long term contact to vibrations can induce the cracks to be transmitted through the structural members of the building that can compromise the structural integrity of the structure. The Ozanam Building of Adamson University is situated near the Romualdez Street, which is considered as one of the main routes of cargo trucks and other heavy vehicles from the Manila North Harbor Port. It was observed that cracks were visible on the façade of the building. For that reason, the structural integrity of Ozanam Building was evaluated against the traffic-induced vibrations using vibration meter. It was found out that the maximum peak particle velocity present in Ozanam Building is 8.60 mm/s which means that the building is safe and below the threshold value for risk in structural damage. Thus, vibration due to traffic has no significant effect that can cause structural damage to the building. In addition, preventive measures were discussed in this paper to reduce the traffic-induced vibrations to an acceptable level.

Piping System Structural Integrity Simulation for Post LOCA Water Hammer Loads

2002 ◽  
Author(s):  
B. W. Manning ◽  
T. Stevens ◽  
G. Morandin ◽  
R. G. Sauve´ ◽  
R. Richards ◽  
...  
Keyword(s):  
Structural Damage ◽  
Structural Integrity ◽  
Water Hammer ◽  
Piping System ◽  
Linear Modeling ◽  
Linear Elastic ◽  
Beam Elements ◽  
Loss Of Coolant Accident ◽  
Loss Of Coolant ◽  
Non Linear

The Canadian Nuclear Safety Commission (CNSC) required as part of the operating license for Ontario Power Generation’s Darlington Nuclear Generating Station, that the structural integrity of the piping following a loss of coolant accident (LOCA) be demonstrated. This is necessary to ensure that no subsequent pressure boundary failures will impede the ability to maintain fuel cooling. The injection of cold emergency coolant following a LOCA creates the potential for the occurrence of condensation-induced water hammers (CIWH) in the primary heat transport (PHT) system piping. Classical linear elastic piping analysis using the class 1 NB-3656 rules of the ASME Boiler & Pressure Vessel Code failed to demonstrate the adequacy of the piping and/or its supports that were designed using the linear elastic rules of subsection NF for nine of the twelve piping models that comprise the PHT system. A decision was made to undertake a state-of-the-art non-linear explicit analysis in order to qualify the piping. Strain rather than stress limits would be applied similar to those being developed by ASME for nuclear packaging undergoing accidental impact during transportation. In order to address the feasibility of this approach, a non-linear analysis was performed on a portion of one of the piping systems. The piping was modeled as shells and again as beam elements with and without detailed modeling of the supports. After these initial simulations, it was determined that the piping could be modeled with simplified beam elements, however, the supports would require a more detailed modeling in order to determine the extent of support damage and the effect the supports have on the integrity of the piping system itself. This paper addresses the non-linear modeling of the piping models and discusses the modeling details, assumptions and analysis results. This approach is shown to be a useful alternative for predicting the extent of structural damage that can be expected by a Level D event such as a condensation induced water hammer following a loss of coolant accident.

2D and 3D Unsteady Flow in Squirrel-Cage Centrifugal Fan and Aeroacoustic Behavior

2006 ◽  
Author(s):  
M. Younsi ◽  
F. Bakir ◽  
S. Kouidri ◽  
R. Rey
Keyword(s):  
Unsteady Flow ◽  
Numerical Models ◽  
Pressure Fluctuations ◽  
Internal Flow ◽  
Navier Stokes ◽  
Computational Domain ◽  
Centrifugal Fan ◽  
Geometry Modeling ◽  
3D Unsteady Flow ◽  
2D And 3D

The objective of this paper is the study and the analysis of the complex phenomena related to the internal flow in a centrifugal fan, using Computational Fluid Dynamics (CFD) tools, completed with experimental investigation in order to validate the used numerical models. The CFD analysis concerns 2D and 3D unsteady flow. The studied phenomena are the interactions and unsteadiness induced by the motion of the rotating blades relatively to the volute and their impact on the aeroacoustic behavior of the fan. Thus, 3D and 2D unsteady calculations using Unsteady Reynolds Averaged Navier Stokes (URANS) approach has been applied on a hybrid mesh grid whose refinement has been studied and adapted to the flow morphology. Turbulence has been modeled with the k-ω-Shear Stress Model (SST) model. The computational domain has been divided into two zones, a rotating zone including the impeller and stationary zone including the volute. A sliding mesh technique has been applied to the interfaces in order to allow the unsteady interactions between the two zones. The overall performances predicted by the computations have been validated at different flow rate. For each geometry modeling (2D and 3D), the unsteady part of the study is illustrated by analyzing the pressure fluctuations on different points from the lateral surface of the volute. The analysis of the wake generated by the rotation of the blower shows that the volute tongue is the main zone of unsteadiness and flow perturbations. In order to predict the acoustic pressures, the unsteady flow field variables provided by the CFD calculations have been used as inputs in the Ffowks Williams-Hawkings equations.

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