Computational fluid dynamics (CFD) investigation of the gas–solid flow and performance of Andersen cascade impactor

Purpose Using the computational fluid dynamics (CFD) technique, this paper aims to investigate the influence of key parameters such as throat diameter; the suction ratio on the flow field behaviors such as Mach number; pressure; and temperature. Design/methodology/approach To investigate the effect of throat diameter, it is simulated for 4, 6, 8 and 10 mm as throat diameters. The governing equations have been solved by standard code of Fluent Software together with a compressible 2 D symmetric and turbulence model with the standard k–ε model. First, the influence of the throat diameter is investigated by keeping the inlet mass flow constant. Findings The results show that a place of shock wave creation is changed by changing the throat diameter. The obtained results illustrate that the maximum amount of Mach number is dependent on the throat diameter. It is obtained from the results that for smaller throats higher Mach numbers can be obtained. Therefore, for mixing purposes smaller throats and for exhausting bigger throats seems to be appropriate. Originality/value The obtained numerical results are compared to the existing experimental ones which show good agreement.

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Analyses of the Compressor Performance Impacts of Centrifugal Compressor Scroll Deformation Due to Installation

Volume 5: Industrial and Cogeneration; Microturbines and Small Turbomachinery; Oil and Gas Applications; Wind Turbine Technology ◽

10.1115/gt2010-22015 ◽

2010 ◽

Author(s):

C. Xu ◽

R. S. Amano

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Centrifugal Compressor ◽

Local Deformation ◽

Discharge Pipe ◽

Gas Compression ◽

Study Results ◽

Computational Fluid Dynamics Cfd ◽

Compressor Performance ◽

And Performance

Centrifugal compressors have widely applications in industrial gas compression processes. Limitations of installation and compressor package always request to modify the compressor geometry to fit certain constrains. Very often, the modifications of the scroll were performed to meet the space constrains. To meet the installation and package requirements, we always modify the scroll and discharge pipe of the compressors. In this study, an original designed scroll and a modified scroll were analyzed by using the Computational Fluid Dynamics (CFD). The study is focused on the performance impacts of the scroll local deformation due to installation constrains. The CFD showed favorable agreements with experiments for original scroll. The detailed flow characters and performance impacts were discussed and results showed that current modifications of the scroll did not have significant impacts to the compressor performance. The study results can be used as a basic guidance for a compressor manufactures.

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An investigation into contracted loaded tip propellers using computational fluid dynamics (CFD)

10.24868/issn.2515-818x.2018.057 ◽

2018 ◽

Author(s):

N R J Williams

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Test Data ◽

Experimental Test ◽

Performance Improvements ◽

Computational Fluid Dynamics Cfd ◽

And Performance ◽

Cfd Method ◽

Developed Pressure

This paper investigates the potential performance improvements of adding contracted loaded tips to propellers. A Wageningen B5-75 Series propeller has been simulated and verified against published experimental test data. Contracted tips have then been added to a Wageningen propeller and the modified propeller then simulated. A CFD method and model has been developed. Pressure, velocity and vector plots have all been analysed detailing the mechanism behind the contracted tips. Limitations behind this method have been explored and explained, and recommendations for further studies made. The development of a database of propeller characteristics and performance chart data to allow quick evaluation of designs has also been proposed.

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Integrated Approach to Multiphase Flow Regime Prediction Through Computational Fluid Dynamics CFD

10.4043/31096-ms ◽

2021 ◽

Author(s):

Matt Straw ◽

Ravindra Aglave ◽

Rodolfo Piccioli

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Multiphase Flow ◽

Case Studies ◽

Cfd Simulation ◽

Process Systems ◽

Computational Fluid Dynamics Cfd ◽

And Performance ◽

Modelling Methods ◽

Modelling Approaches

Abstract This paper presents recent advances in multiphase modelling methods in Computational Fluid Dynamics (CFD). It uses case studies to show how integration of advanced multiphase modelling approaches can improve the fidelity and realism of simulation of separation and process systems; helping improve design and performance. CFD has been widely used to aid the design and operational performance of many separation and multiphase production and process systems; often providing significant insight and performance improvement. Traditionally, numerous compromises or simplifications must be made when simulating complex multiphase flows and their transitions within production and separation systems using CFD. For example, the modelling methods applicable to capture gas-liquid or liquid-liquid interface behaviour are not suitable (or practical) to also capture gas columns, liquid films or liquid entrainment phenomena, that may be important to quantifying overall system performance. To accommodate different multiphase phenomena and flow regimes, multiple CFD simulations or approaches have often been required. This can limit the insight or fidelity of a given simulation or, in some cases, mean overall performance cannot be fully quantified (even though useful performance indicators may still be identified). Here, the authors present advances in hybrid multiphase modelling and how integration of multiphase modelling approaches enables multiple multiphase flow regimes and their transition to be captured through CFD simulation. The paper will demonstrate how these advances enables simulation of more complex behaviours with increased fidelity. Examples, case studies and validation cases are presented demonstrating phenomena including bulk liquid interface break-up, liquid film formation and entrainment of droplets plus their break—up and deposition. The examples will be presented in the context of the improvements possible in simulation fidelity and realism, of multiphase systems, and how this can impact the insight and value gained from CFD simulation in this complex field. The work presented shows how new developments and evolution of CFD-based predictions can advance how the industry uses this approach and the value that can be obtained. It highlights how integration of the most advanced modelling approaches and methods is key to the next stage of application of CFD to enable better representation of the full range of fluid mechanics that are critical to many separation and multiphase system designs and performance.

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Dynamic Instability Analysis of a Spring-Loaded Pressure Safety Valve Connected to a Pipe by Using Computational Fluid Dynamics Methods

Journal of Pressure Vessel Technology ◽

10.1115/1.4049697 ◽

2021 ◽

Vol 143 (4) ◽

Author(s):

Fengjie Zheng ◽

Chaoyong Zong ◽

Chao Zhang ◽

Xueguan Song ◽

Fuzheng Qu ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Dynamic Instability ◽

Design Parameters ◽

Wave Forces ◽

Cfd Model ◽

Pressure System ◽

System Pressure ◽

Computational Fluid Dynamics Cfd ◽

And Performance

Abstract As the ultimate protection of a pressure system, pressure safety valves (PSV) can respond in an unstable manner in the form of flutter and chatter, which will affect service life, reliability, and performance. In order to study the dynamic instability caused by multisource forces including the flow force, the spring compression force, and the pressure wave forces, a high-fidelity computational fluid dynamics (CFD) model of the system is proposed. A complete CFD model, incorporating the PSV, connected pipes, and the pressure vessel, is developed, in which advanced techniques in Fluent using User Defined Function (UDF) and Dynamic Layering method are combined to allow the PSV to be coupled to the system dynamics. Based on this model, the valve's opening and reclosing process is monitored to examine the influence of design parameters on the dynamic instability of the PSV. Specifically, the propagation of pressure waves along the connecting pipes is successfully captured, helping to assess the instability mechanism and provide the ability to optimize the design and setup of pressure relief systems.

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