Investigation of Mathematical Model of Turbulent Flow for Marine Propeller

2015 ◽  
Author(s):  
Nilima C. Joshi ◽  
Ayaz J. Khan
Keyword(s):  
Modern Technology ◽  
Hydrodynamic Performance ◽  
Marine Propeller ◽  
Turbulent Model ◽  
Complex Flow ◽  
Ansys Fluent ◽  
Flow Phenomena ◽  
Fluent Software ◽  
Effective Design ◽  
Mathematical And Numerical Modeling

ost of the flow phenomena important to modern technology involve turbulence. Propellers generally operate in the very complex flow field that may be highly turbulent and spatially non-uniform. Propeller skew is the single most effective design parameter which has significant influence on reducing propeller induced vibration. Up to date applications of propeller skew does not has a specified criteria for any turbulent model. This paper deals with the model which explains the effect of propeller skewness on hydrodynamic performance related to study of turbulent model via mathematical and numerical modeling. The simulation work is carried out using ANSYS-FLUENT software.

Numerical Analysis of Hydrodynamic Propeller Performance of LNG Carrier in Open Water

2014 ◽  
Vol 66 (2) ◽  
Author(s):  
M. Nakisa ◽  
A. Maimun ◽  
Yasser M. Ahmed ◽  
Jaswar Jaswar ◽  
A. Priyanto ◽  
...  
Keyword(s):  
Open Water ◽  
Hydrodynamic Performance ◽  
Marine Propeller ◽  
Turbulent Model ◽  
Propeller Blade ◽  
Hydrodynamic Parameters ◽  
Laboratory Facilities ◽  
Mesh Density ◽  
Propeller Performance ◽  
Marine Laboratory

Marine propeller blade geometries, especially LNG carriers, are very complicated and determining the hydrodynamic performance of these propellers using experimental work is very expensive, time consuming and has many difficulties in calibration of marine laboratory facilities. This paper presents the assessment on the effect of turbulent model and mesh density on propeller hydrodynamic parameters. Besides that, this paper focuses on the LNG carrier Tanaga class propeller hydrodynamic performance coefficients such as Kt, Kq and η, with respect to the different advance coefficient (j). Finally, the results from numerical simulation that were calculated based on RANS (Reynolds Averaged Navier Stocks) equations, were compared with existing experimental results, followed by analysis and discussion sections. As a result the maximum hydrodynamic propeller efficiency occurred when j=0.84.

Prediction on Hydrodynamic Performances of Propeller by OpenFOAM

2009 ◽  
Author(s):  
Wei Li ◽  
Chi Yang ◽  
Lijun Yu ◽  
Guoqiang Wang ◽  
Yunxiang You
Keyword(s):  
Experimental Data ◽  
Open Source ◽  
Cavity Flow ◽  
Second Order ◽  
Turbulent Model ◽  
Complex Flow ◽  
Flow Phenomena

In this paper the flow around a propeller is simulated by open source CFD tool-OpenFOAM. In order to validate the availability of OpenFOAM code in the field of propeller theory, the steady hydrodynamic performances of DTMB P4119 propeller is predicted. The discrete schemes are second order upwind. The grids are generated by GAMBIT software. The dependence of grid number and adaptability of turbulent model are studied. Compared with the experimental data, it shows that the OpenFOAM code can be used effectively to predict the hydrodynamic performances of the propeller in practice. It can be developed further to study more complex flow phenomena such as cavity flow and other unconventional propulsors.

A Co-Simulation Approach to Modeling Air-Cooled Condensers in Windy Conditions

2020 ◽  
Author(s):  
Ruan Engelbrecht ◽  
Ryno Laubscher ◽  
Johan van der Spuy
Keyword(s):  
System Level ◽  
Analysis Tool ◽  
Steam Quality ◽  
Complex Flow ◽  
Accurate Analysis ◽  
Ansys Fluent ◽  
Wind Speeds ◽  
Air Cooled Condensers ◽  
Flow Phenomena ◽  
Adverse Environmental Conditions

Abstract Air-cooled condensers (ACC) are commonly used for cooling applications in the petro-chemical and power generation industry. Common analysis techniques used include one-dimensional design codes, however, these fail to capture complex flow phenomena associated with ACCs subjected to adverse environmental conditions. Computational Fluid Dynamics (CFD) is seen as an alternative, more accurate analysis tool. The model used in the present study co-simulates the CFD using ANSYS Fluent® to model the air-side with a system-level model in Flownex® to represent the steam-side. A 4 × 3 ACC bank is subjected to adverse cross-wind conditions and a single cell is co-simulated. The volumetric and thermal performance is predicted. Prior to the evaluation a discretization process is undertaken to ascertain an adequate level of detail required to accurately capture the complex flow phenomena which could affect the steam-side performance. A 3 × 3 and 6 × 6 discretization case is compared. A 13% difference in heat transfer rate is predicted between the cases. The 6 × 6 case is used to evaluate the cell performance when the ACC is subjected to cross-wind speeds of 0, 3, 6 and 9 m/s. Results show an increase in outlet steam quality as the cross-wind speed increases due to diminishing ACC performance.

An Investigation of the Effect of interrupted fin arrangements on the Thermal Performance of a Heat Sink under a Free Convection Condition

2019 ◽  
Vol 7 (1) ◽  
pp. 43-53
Author(s):  
Abbas Jassem Jubear ◽  
Ali Hameed Abd
Keyword(s):  
Heat Transfer ◽  
Steady State ◽  
Natural Convection ◽  
Thermal Performance ◽  
Heat Sink ◽  
Numerical Study ◽  
Ansys Fluent ◽  
Fluent Software ◽  
Steady State Heat ◽  
Steady State Heat Transfer

The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model.  The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.

scholarly journals Numerical Investigation of an Optimized Rotor Head Fairing for the RACER Compound Helicopter in Cruise Flight

Aerospace ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 66
Author(s):  
Patrick Pölzlbauer ◽  
Andreas Kümmel ◽  
Damien Desvigne ◽  
Christian Breitsamter
Keyword(s):  
Drag Reduction ◽  
Design Optimization ◽  
Cost Effective ◽  
Aerodynamic Design ◽  
Ansys Fluent ◽  
Aerodynamic Design Optimization ◽  
Flow Phenomena ◽  
Compound Helicopter ◽  
Rotor Head ◽  
Cruise Flight

The present work is part of the Clean Sky 2 project Full-Fairing Rotor Head Aerodynamic Design Optimization (FURADO), which deals with the aerodynamic design optimization of a full-fairing rotor head for the Rapid And Cost-Effective Rotorcraft (RACER) compound helicopter. The rotor head is a major drag source and previous investigations have revealed that the application of rotor head fairings can be an effective drag reduction measure. As part of the full-fairing concept, a new blade-sleeve fairing was aerodynamically optimized for cruise flight. Within this publication, the newly developed blade-sleeve fairing is put to test on an isolated, five-bladed rotor head and compared to an already existing reference blade-sleeve fairing, which was developed at Airbus Helicopters. Numerical flow simulations are performed with ANSYS Fluent 2019 R2 considering a rotating rotor head with cyclic pitch movement. The aerodynamic forces of the isolated rotor head are analyzed to determine the performance benefit of the newly developed blade-sleeve fairing. A drag reduction of 4.7% and a lift increase of 20% are obtained in comparison to the Airbus Helicopters reference configuration. Furthermore, selected surface and flow field quantities are presented to give an overview on the occurring flow phenomena.

Research on the Impacts of Screw Speed on All-Metal Screw Pump

2014 ◽  
Vol 703 ◽  
pp. 425-429
Author(s):  
Jun Fei Wu ◽  
Zhi Li ◽  
Fan Guo Meng ◽  
Ben Liang Yu
Keyword(s):  
Geometric Model ◽  
Constraint Condition ◽  
3D Flow ◽  
Screw Speed ◽  
Ansys Fluent ◽  
Screw Pump ◽  
Single Screw ◽  
Dynamic Mesh Technique ◽  
Fluent Software ◽  
Mesh Technique

Compared with traditional screw pump,all-metal screw pump have more advantages in the oil extraction. In this paper, all-metal single screw pump's geometric model was made by PROE software; then the dynamic mesh technique was applied to mesh the model and constraint condition was applied in the ANSYS-FLUENT software. 3D flow field was numerical analyzed In that software, the impacts of screw speed on volume flow and volumetric efficiency were concluded, the conclusion can offer some valuable guidances to the all-metal single screw pump's design.

Influence of Thermal Plume on Particle Inhalability of a Lying Mannequin in a Room

2021 ◽  
Author(s):  
Maryam Habibi ◽  
Mohsen Heidary ◽  
Mohammad Mehdi Tavakol ◽  
Goodarz Ahmadi
Keyword(s):  
Respiratory System ◽  
Spherical Particles ◽  
Thermal Plume ◽  
Ansys Fluent ◽  
Thermal Plumes ◽  
Micro Particles ◽  
Upward Direction ◽  
Fluent Software ◽  
Turbulence Dispersion ◽  
Aspiration Efficiency

Abstract In this study, the dispersion and deposition of particles in the respiratory system attached to a mannequin lying down inside a room were investigated numerically. The respiratory system model was prepared by processing the CT scan images of a volunteer and was attached to a mannequin lying in the middle of a room. The flow field around the mannequin and effects of the thermal plume on the particle aspiration by the mannequin model was simulated using the Ansys-Fluent software. The aspiration efficiency of spherical particles in the airway was studied with the Lagrangian particle trajectory analysis, including the turbulence dispersion effects. For validation of numerical simulations, the aspiration efficiency of the particles obtained from the numerical solution was compared with the case of a standing mannequin. The results are presented for two different modes with upward and downward thermal plumes. For the first mode, due to the strong effect of the thermal plume in the upward direction, the aspiration efficiency of midrange particles increases. However, the aspiration efficiency of large micro-particles decreases for the first mode. For the second mode, with the downward thermal plume, the aspiration efficiency of small micro-particles increases significantly.

Granular Flow Modeling and Simulation Using a Dynamic Finite Element Method

2007 ◽  
Author(s):  
M. A. Kabir ◽  
C. Fred Higgs ◽  
Michael R. Lovell
Keyword(s):  
Finite Element ◽  
Modeling And Simulation ◽  
Granular Flow ◽  
Flow Behavior ◽  
Food Service ◽  
Complex Nature ◽  
Complex Flow ◽  
Dual Nature ◽  
Simulation Techniques ◽  
Flow Phenomena

Granular flow behavior is of fundamental interest to the engineering and scientific community because of the prevalence of these flows in the pharmaceutical, agricultural, food service, and powder manufacturing industries. Granular materials exhibit very complex behavior, oftentimes acting as solids and at other times as fluids. This dual nature leads to very complex and rich behavior, which is not yet well understood. Therefore, the present investigation introduces a new technique that can potentially be used to unveil the mystery of granular flow phenomena. To this end, advanced finite element modeling and simulation techniques have been applied to the study of the complex nature of granular flow. More specifically, the explicit dynamic code LS-DYNA has been utilized to gain an understanding of the complex flow nature and collision stresses of granules in a shear cell.

Performance Modeling of Ducted Vertical Axis Turbine Using Computational Fluid Dynamics

2013 ◽  
Vol 47 (4) ◽  
pp. 36-44 ◽  
Author(s):  
Prasun Chatterjee ◽  
Raymond N. Laoulache
Keyword(s):  
Performance Modeling ◽  
Flow Direction ◽  
Computational Cost ◽  
Vertical Axis ◽  
Area Ratio ◽  
Diameter Ratio ◽  
Turbulent Model ◽  
Ansys Fluent ◽  
Second Order In Time ◽  
Vertical Axis Turbine

AbstractVertical axis turbines (VATs) excel over horizontal axis turbines in their independent flow direction. VATs that operate in an enclosure, e.g., a diffuser shroud, are reported to generate more power than unducted VATs. A diffuser-shrouded, high solidity of 36.67%, three-blade VAT with NACA 633-018 airfoil section is modeled in 2-D using the commercial software ANSYS-FLUENT®. Incompressible, unsteady, segregated, implicit, and second order in time and space solver is implemented in association with the Spalart-Allmaras turbulent model with a reasonable computational cost. The computational results are assessed against experimental data for unducted VAT at low tip speed ratios between 1 and 2 for further numerical analysis on diffuser models. Different diffuser designs are investigated using suitable nozzle size, area ratio, length-to-diameter ratio and angles between the diffuser inner surfaces. The numerical model shows that, for a specific diffuser design, the ducted VAT performance coefficient can be augmented by almost 90% over its unducted counterpart.

scholarly journals Solution of the conjugate problem of gas dynamics and heat transfer in structures with a large ratio of geometric scale values

2017 ◽  
pp. 69-74
Author(s):  
D. A. Romanyuk ◽  
S. V. Panfilov ◽  
D. S. Gromov
Keyword(s):  
Gas Dynamics ◽  
Software Package ◽  
Thermal State ◽  
Mathematical Formulation ◽  
Research Work ◽  
Conjugate Problem ◽  
Thermal Processes ◽  
Ansys Fluent ◽  
Fluent Software ◽  
Volume Method

Within the scope of the research work, we have developed the methods and software package for solving the conjugate heat and hydraulic problems based on the classical approach to performing hydraulic calculations and modeling thermal processes by means of the finite volume method in the ANSYS Fluent software package. The developed means allowed us to efficiently calculate the thermal state of complex technical objects. The study gives mathematical formulation of the methods and suggests the results of their approbation and verification

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