scholarly journals Numerical simulation of an industrial centrifugal fan 5,5 kW with OpenFOAM

2020 ◽  
Vol 3 (4) ◽  
pp. first
Author(s):  
Khánh Hiếu Ngô ◽  
Long Văn Lê ◽  
Huy Đình Anh Lê
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Reliable Data ◽  
Performance Characteristics ◽  
Centrifugal Fan ◽  
Centrifugal Forces ◽  
Mechanical Device ◽  
Pressure Region ◽  
The Cost ◽  
High Pressure Region

Centrifugal fan is a mechanical device working on the principle of centrifugal pump. When working, propeller sucks air along the axis, the pressure at the fan center will be small. The air will move from high pressure region to where the pressure is low. In other words, the air will receive additional centrifugal forces. The appearance of centrifugal fan has brought us many benefits such as basement ventilation systems or where ventilation fans enable to be directly established. Hence, the study of the performance characteristics of centrifugal fan is currently a matter concern, from which the improvement of performance can be applied to the fan. In this paper, a model simulating the performance characteristics of centrifugal fan was done on snappyHexMesh ultility with mainly hexahedron girds. Therefore, the results of the performance characteristics of centrifugal fan use k – omega SST is compared with experimental data. The results obtained from automatic meshing snappyHexmesh ultility and the SimpleFoam solver of open source OpenFOAM software provide the reliable data in the design and calculation of centrifugal fan. On this basis, the cost of improving the performance of centrifugal fan can be reduced considerably by numerical simulation.

Numerical Simulation of Blast Wave Propagating on the Soil Surface

2014 ◽  
Vol 602-605 ◽  
pp. 3256-3260
Author(s):  
Xiao Yong Li ◽  
Cun Yan Cui ◽  
Jing Peng Chen ◽  
Yun Chun Jiang ◽  
Bei Lei Zhao ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
High Pressure ◽  
Comparative Analysis ◽  
Blast Wave ◽  
Soil Surface ◽  
Low Pressure ◽  
Pressure Region ◽  
High Pressure Region

A numerical simulation of TNT explosion on the soil surface is presented in this paper. It demonstrates how the blast wave propagates on the soil surface and interacts with the soil surface. Compared with the explosion in air, a comparative analysis on the distribution of the shock wave overpressure is implemented. The results show that the space on the soil surface close to the explosion source can be divided into a relatively high pressure region and a relatively low pressure region. Moreover, by defining the scaled height H, the interface of two regions comes about H = 0.35.

Evaluation Of The Functional Of Space-Planning Arrangement Of A Building

2019 ◽  
pp. 4-9
Keyword(s):  
Numerical Simulation ◽  
Life Cycle ◽  
Initial Data ◽  
Objective Assessment ◽  
Objective Evaluation ◽  
Point Of View ◽  
Shopping Centers ◽  
Space Planning ◽  
Planning Decisions ◽  
The Cost

The article focuses on the problem of the lack of objective evaluation of space-planning arrangement of buildings as a creative approach of the architect to the performing of functional tasks by the object. It is proposed to create a methodology for assessing the functional of space-planning solutions of buildings on the basis of numerical simulation of functional processes using the theory of human flows. There is a description of the prospects of using this method, which makes it possible to increase the coefficient of compactness, materials and works saving, more efficient use of space, reduce the cost of the life cycle of the building, save human forces and time to implement the functional of the building. The necessary initial data for modeling on the example of shopping and shopping-entertainment centers are considered. There are three main tasks for algorithmization of the functional of shopping centers. The conclusion is made about necessity of development of a method for objective assessment of buildings from the point of view of ergonomics of space-planning decisions based on the study of human behavior in buildings of different purposes.

scholarly journals Simplified Mathematical Modelling of Uncertainty: Cost-Effectiveness of COVID-19 Vaccines in Spain

Mathematics ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 566
Author(s):  
Julio Emilio Marco-Franco ◽  
Pedro Pita-Barros ◽  
Silvia González-de-Julián ◽  
Iryna Sabat ◽  
David Vivas-Consuelo
Keyword(s):  
Cost Effectiveness ◽  
Health Planning ◽  
Cost Effective ◽  
Incremental Cost Effectiveness Ratio ◽  
Reliable Data ◽  
Simplified Model ◽  
Fatality Rate ◽  
Cost Effectiveness Ratio ◽  
Funeral Homes ◽  
The Cost

When exceptional situations, such as the COVID-19 pandemic, arise and reliable data is not available at decision-making times, estimation using mathematical models can provide a reasonable reckoning for health planning. We present a simplified model (static but with two-time references) for estimating the cost-effectiveness of the COVID-19 vaccine. A simplified model provides a quick assessment of the upper bound of cost-effectiveness, as we illustrate with data from Spain, and allows for easy comparisons between countries. It may also provide useful comparisons among different vaccines at the marketplace, from the perspective of the buyer. From the analysis of this information, key epidemiological figures, and costs of the disease for Spain have been estimated, based on mortality. The fatality rate is robust data that can alternatively be obtained from death registers, funeral homes, cemeteries, and crematoria. Our model estimates the incremental cost-effectiveness ratio (ICER) to be 5132 € (4926–5276) as of 17 February 2021, based on the following assumptions/inputs: An estimated cost of 30 euros per dose (plus transport, storing, and administration), two doses per person, efficacy of 70% and coverage of 70% of the population. Even considering the possibility of some bias, this simplified model provides confirmation that vaccination against COVID-19 is highly cost-effective.

scholarly journals Fibre-induced drag reduction

2008 ◽  
Vol 602 ◽  
pp. 209-218 ◽  
Author(s):  
J. J. J. GILLISSEN ◽  
B. J. BOERSMA ◽  
P. H. MORTENSEN ◽  
H. I. ANDERSSON
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Reynolds Number ◽  
Drag Reduction ◽  
Elastic Layer ◽  
Turbulent Drag Reduction ◽  
Rigid Polymer ◽  
Fibre Concentration ◽  
Induced Drag ◽  
Turbulent Drag

We use direct numerical simulation to study turbulent drag reduction by rigid polymer additives, referred to as fibres. The simulations agree with experimental data from the literature in terms of friction factor dependence on Reynolds number and fibre concentration. An expression for drag reduction is derived by adopting the concept of the elastic layer.

A correlation to predict the performance characteristics of centrifugal pumps handling slurries

1997 ◽  
Vol 211 (2) ◽  
pp. 147-157 ◽  
Author(s):  
K A Kazim ◽  
B Maiti ◽  
P Chand
Keyword(s):  
Experimental Data ◽  
Particle Size ◽  
Suspended Solids ◽  
Reduction Factor ◽  
Performance Characteristics ◽  
Centrifugal Pumps ◽  
Pump Performance ◽  
New Correlation ◽  
Effect Of Particle Size ◽  
The Individual

Centrifugal pumps are being used increasingly for transportation of slurries through pipelines. To design a slurry handling system it is essential to have a knowledge of the effects of suspended solids on the pump performance. A new correlation to predict the head reduction factor for centrifugal pumps handling solids has been developed. This correlation takes into account the individual effect of particle size, particle size distribution, specific gravity and concentration of solids on the centrifugal pump performance characteristics. The range of validity of the correlation has been verified by experiment and by using experimental data available from the literature. The present correlation shows better agreement with the experimental data than existing correlations.

Based on Numerical Simulation of High-Performance Parallel Machine Muffler Experimental Calibration

2013 ◽  
Vol 718-720 ◽  
pp. 1645-1650
Author(s):  
Gen Yin Cheng ◽  
Sheng Chen Yu ◽  
Zhi Yong Wei ◽  
Shao Jie Chen ◽  
You Cheng
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Boundary Element ◽  
Message Passing ◽  
High Performance ◽  
Message Passing Interface ◽  
Parallel Machine ◽  
Simulation Software ◽  
Experimental Calibration ◽  
The Cost

Commonly used commercial simulation software SYSNOISE and ANSYS is run on a single machine (can not directly run on parallel machine) when use the finite element and boundary element to simulate muffler effect, and it will take more than ten days, sometimes even twenty days to work out an exact solution as the large amount of numerical simulation. Use a high performance parallel machine which was built by 32 commercial computers and transform the finite element and boundary element simulation software into a program that can running under the MPI (message passing interface) parallel environment in order to reduce the cost of numerical simulation. The relevant data worked out from the simulation experiment demonstrate that the result effect of the numerical simulation is well. And the computing speed of the high performance parallel machine is 25 ~ 30 times a microcomputer.

Application and Research of Digital Technology in Optimal Design of CNC Floor Boring and Milling Machine

2012 ◽  
Vol 429 ◽  
pp. 111-115
Author(s):  
Zhen Long Leng ◽  
Jin Feng Yang ◽  
Qun Ping Liu ◽  
Xun Deng
Keyword(s):  
Numerical Simulation ◽  
Optimal Design ◽  
Digital Technology ◽  
Three Dimensional ◽  
Milling Machine ◽  
Machine Model ◽  
Digital Modeling ◽  
Key Technologies ◽  
The Cost ◽  
Interference Checking

This paper focuses on application of the three-dimensional digital modeling, numerical analysis and optimization, digital control and other key technologies which provide technical support for the design and development in CNC floor boring and milling machine manufactruing. The three-dimensional digital modeling, digital assembly, interference checking help to eliminate some hidden trouble before processing and assembly. Numerical simulation reduces the cost and shortens the cycle of designand manufactruing in the optimal design of the machine. This technique has been successfully applied to a CNC Floor Boring and Milling Machine Model, which has been running for three years and achieved satisfactary economic result.

Investigation of Emulsion Flow in Steam-Assisted Gravity Drainage

SPE Journal ◽  
2013 ◽  
Vol 18 (03) ◽  
pp. 440-447 ◽  
Author(s):  
C.C.. C. Ezeuko ◽  
J.. Wang ◽  
I.D.. D. Gates
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Oil Recovery ◽  
Vital Role ◽  
Gravity Drainage ◽  
Steam Assisted Gravity Drainage ◽  
Emulsion Flow ◽  
Very High ◽  
Effective Representation

Summary We present a numerical simulation approach that allows incorporation of emulsion modeling into steam-assisted gravity-drainage (SAGD) simulations with commercial reservoir simulators by means of a two-stage pseudochemical reaction. Numerical simulation results show excellent agreement with experimental data for low-pressure SAGD, accounting for approximately 24% deficiency in simulated oil recovery, compared with experimental data. Incorporating viscosity alteration, multiphase effect, and enthalpy of emulsification appears sufficient for effective representation of in-situ emulsion physics during SAGD in very-high-permeability systems. We observed that multiphase effects appear to dominate the viscosity effect of emulsion flow under SAGD conditions of heavy-oil (bitumen) recovery. Results also show that in-situ emulsification may play a vital role within the reservoir during SAGD, increasing bitumen mobility and thereby decreasing cumulative steam/oil ratio (cSOR). Results from this work extend understanding of SAGD by examining its performance in the presence of in-situ emulsification and associated flow of emulsion with bitumen in porous media.

A Numerical Investigation on the Volute/Diffuser Interaction due to the Axial Distortion at Impeller Exit

2000 ◽  
Author(s):  
Fahua Gu ◽  
Abraham Engeda ◽  
Mike Cave ◽  
Jean-Luc Di Liberti
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Numerical Investigation ◽  
Steady Flow ◽  
Centrifugal Compressor ◽  
Vortex Structure ◽  
Flow Model ◽  
Single Stage ◽  
Mass Flows

Abstract A numerical simulation is performed on a single stage centrifugal compressor using the commercially available CFD software, CFX-TASCflow. The steady flow is obtained by circumferentially averaging the exit fluxes of the impeller. Three runs are made at design condition and off-design conditions. The predicted performance is in agreement with experimental data. The flow details inside the stationary components are investigated, resulting in a flow model describing the volute/diffuser interaction at design and off-design conditions. The recirculation and twin vortex structure are found to explain the volute loss increase at lower and higher mass flows, respectively.

HYDROGEN — ZERO CARBON FOOTPRINT

2021 ◽  
Vol 7 (1) ◽  
pp. 10-25
Author(s):  
Mikhail V. Gordin ◽  
Valery I. GUROV ◽  
Anton N. Varyukhin ◽  
Alexander V. Geliev ◽  
Elena V. SHCHERBAKOVA
Keyword(s):  
Power Systems ◽  
The Past ◽  
Long Term Storage ◽  
Strategic Direction ◽  
Pressure Region ◽  
Zero Carbon ◽  
World Class ◽  
High Pressure Region ◽  
Term Storage

This article presents Russia’s main achievements of over the past 65 years in the development of an advanced scientific and technical groundwork for the introduction of hydrogen as a fuel in various energy systems. On the basis of the obtained world-class results, the authors argue for the necessity of creating a Center for Hydrogen Innovative Development (CVIR) with the decisive participation of enterprises with real experience in obtaining liquid hydrogen (H2l) with the possibility of its long-term storage. A concept has been formulated for the development of breakthrough technological solutions for the widespread use of hydrogen as an efficient and environmentally friendly (without the formation of carbon oxides) fuel in various power systems within the framework of the CVIR. In particular, the strategic direction of the CVIR project was developed in order to create a developed infrastructure for the reliable provision of vehicles with the required amount of fuel in a limited period of time. This can be achieved by applying the method of cryogenic filling of transport cylinders, taking into account the real properties of hydrogen in the ultra-high pressure region (70 MPa and above). The results have revealed possibilities for further building up the advanced scientific and technical groundwork for the broad promotion of hydrogen in the energy complex of Russia, which is presented in the CVIR project. In addition, the authors have compared the developed technologies with foreign analogues.

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