A Simulation Research on the Noise and Flow of Vehicle Cooling Fans

2011 ◽  
Vol 199-200 ◽  
pp. 988-994
Author(s):  
Zhao Cheng Yuan ◽  
Fu Quan Zhao ◽  
Hai Bo Chen ◽  
Jia Yi Ma
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Numerical Simulation ◽  
Aerodynamic Noise ◽  
Cfd Model ◽  
Simulation Research ◽  
Cooling Fan ◽  
Light Duty ◽  
Cooling Fans ◽  
Computational Fluid Dynamics Cfd

This paper optimized the design of the cooling fans of a light-duty diesel engine through numerical simulation. Using Fluent as a platform, a detailed Computational fluid dynamics (CFD) model was developed to simulate both the aerodynamic and the acoustics performance. The model developed was validated against experimental data obtained in this research. The validated model was then used to optimize the design of the cooling fan aiming to minimize the operation noise. With the guarantee of cooling performances, the aerodynamic noise of the two fans has been successfully reduced.

Effects of Over Fire Air on the Combustion and NOx Emission Characteristics of a 600 MW Opposed Swirling Fired Boiler

2012 ◽  
Vol 512-515 ◽  
pp. 2135-2142 ◽  
Author(s):  
Yu Peng Wu ◽  
Zhi Yong Wen ◽  
Yue Liang Shen ◽  
Qing Yan Fang ◽  
Cheng Zhang ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Empirical Method ◽  
Nox Emission ◽  
Emission Characteristics ◽  
Cfd Model ◽  
Nitrogen Release ◽  
Computational Fluid Dynamics Cfd ◽  
Low Nox Emission

A computational fluid dynamics (CFD) model of a 600 MW opposed swirling coal-fired utility boiler has been established. The chemical percolation devolatilization (CPD) model, instead of an empirical method, has been adapted to predict the nitrogen release during the devolatilization. The current CFD model has been validated by comparing the simulated results with the experimental data obtained from the boiler for case study. The validated CFD model is then applied to study the effects of ratio of over fire air (OFA) on the combustion and nitrogen oxides (NOx) emission characteristics. It is found that, with increasing the ratio of OFA, the carbon content in fly ash increases linearly, and the NOx emission reduces largely. The OFA ratio of 30% is optimal for both high burnout of pulverized coal and low NOx emission. The present study provides helpful information for understanding and optimizing the combustion of the studied boiler

scholarly journals Application of CFD to the Design of Multirun Meter Station With Ultrasonic Meters

1998 ◽  
Author(s):  
Jaroslaw Jelen ◽  
Wojciech Studzinski ◽  
Michael Brown
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Numerical Simulation ◽  
Numerical Model ◽  
Experimental Information ◽  
Out Of Plane ◽  
Ultrasonic Flow Meter ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement ◽  
Subsequent Integration

Designers of ultrasonic meter stations with headers do not have any experimental data which can help to determine proper location of the multipath ultrasonic meter within the meter run. The results of meter tests are limited to such configurations as a single 90° elbows and two elbows out of plane. Because of the variety of header layouts used in practice any experimental information related to this piping configuration will be of limited use in the design process. The proposed approach is based on the application of Computational Fluid Dynamics (CFD) methods to the evaluation of header effects on ultrasonic flow meter using a commercial CFD code combined with a numerical model of the ultrasonic meter. The numerical simulation of the flow field in the header and meter runs and subsequent integration of the obtained velocity field in a numerical model of multipath ultrasonic meter were used to determine the optimal meter position. This approach was validated against available experimental data on the ultrasonic meter performance downstream of single and double elbow. The comparison of simulations and test data has shown very good agreement of trends exhibited by the meter. The trends were replicated by the simulator within approximately 1% for X/D ≥5 and within 0.5% for X/D ≥9.

scholarly journals Numerical Simulation of Flow in Parshall Flume Using Selected Nonlinear Turbulence Models

Hydrology ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 151
Author(s):  
Mehdi Heyrani ◽  
Abdolmajid Mohammadian ◽  
Ioan Nistor
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Numerical Simulation ◽  
Computational Fluid Dynamics ◽  
Standard Error ◽  
Physical Modeling ◽  
Hydraulic Structure ◽  
Turbulence Models ◽  
Computational Fluid Dynamics Cfd ◽  
The Right

This study uses a computational fluid dynamics (CFD) approach to simulate flows in Parshall flumes, which are used to measure flowrates in channels. The numerical results are compared with the experimental data, which show that choosing the right turbulence model, e.g., v2−f and LC, is the key element in accurately simulating Parshall flumes. The Standard Error of Estimate (SEE) values were very low, i.e., 0.76% and 1.00%, respectively, for the two models mentioned above. The Parshall flume used for this experiment is a good example of a hydraulic structure for which the design can be more improved by implementing a CFD approach compared with a laboratory (physical) modeling approach, which is often costly and time-consuming.

Bubble Breakup and Coalescence Modelling for Subsea Gas Releases Using Computational Fluid Dynamics

2018 ◽  
Author(s):  
Kejia Wu ◽  
Johnathan Green ◽  
Subajan Sivandran
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Computational Fluid Dynamics ◽  
Gas Release ◽  
Cfd Model ◽  
The Core ◽  
Bubble Breakup ◽  
Characteristic Behaviour ◽  
Computational Fluid Dynamics Cfd

Bubble breakup and coalescence is a phenomenon which occurs within a developing subsea gas plume. A Computational Fluid Dynamics (CFD) model incorporating bubble breakup and coalescence was developed to describe the behaviour of a subsea gas release and the subsequent rising gas plume. The model was assessed for its suitability in capturing the characteristic behaviour of a rising gas plume by comparing the CFD results with experimental data obtained from underwater gas release experiments. The study shows bubble breakup and coalescence plays a key role in determining the shape and the behaviour of a subsea gas release. Without the bubble breakup and coalescence included in the CFD model a narrower plume width and higher rising velocity is observed when compared to the experimental data. With bubble breakup and coalescence included the results obtained from the CFD model more accurately match the experimental data. Breakup and coalescence is a mechanism which redistributes the energy within the core of the gas plume towards the edge of the plume. This has a significant impact on the plume characteristics and is vital to be included in the CFD model to describe the behaviour of the released gas. The study was carried out using air as the released gas. This was done to compare with the available experimental data where air was used as the source. However the CFD model developed is applicable for hydrocarbon subsea gas releases.

Appraisal of an ESF Radial Plate Clutch With Cooling Flow Using a NNF CFD Solver

2000 ◽  
Author(s):  
Darren J. Ellam ◽  
Raymond J. Atkin ◽  
William A. Bullough
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Steady State ◽  
Fluid Temperature ◽  
Two Dimensional ◽  
Cfd Model ◽  
Viscoplastic Material ◽  
Cooling Flow ◽  
Torque Transmission ◽  
Computational Fluid Dynamics Cfd

Abstract To aid the application of electro-structured fluid (ESF) devices, a virtual two plate radial clutch is examined in a pre-prototyping exercise to estimate the effect of a radial cooling flow on pre-set torque transmission. A throughflow of ESF will act to keep the fluid temperature under control making such devices more reliable over a wider operating range. The ESF is treated as a Bingham viscoplastic material and clutch behaviour is investigated under steady state isothermal conditions. The resulting two-dimensional non-Newtonian fluid (NNF) model is solved using a computational fluid dynamics (CFD) package. The results are partially verified using analytical analysis and compared with sparse experimental data. This work is expected to lead to a more complex CFD model for which analytical methods will not be available. Indications are that, for realistic rates of throughflow, torque transmission should not be overtly affected. Hence the cooling of slipping ESF clutches by throughflow can be contemplated.

scholarly journals Effect of Bench Hood Exhaust Usage on Indoor Air Quality in a Chemical Laboratory

2014 ◽  
Vol 1 ◽  
pp. 14-22
Author(s):  
Ayman A. Shaaban ◽  
Samy M. Morcos ◽  
Essam Eldin Khalil ◽  
Mahmoud A. Fouad
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Computational Fluid Dynamics ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Mole Fraction ◽  
Indoor Air ◽  
Cfd Model ◽  
Ansys Fluent ◽  
Computational Fluid Dynamics Cfd

Indoor air quality inside chemical laboratories subjected to gaseous contaminants was investigated numerically throughout the current research using Ansys Fluent 13. The lab is 4.8 m (L) * 4.3 m (W) * 2.73 m (H). The model was built and mesh was generated using Gambit 2.2.30 yielding around 1.4 million cells. To ensure the reliability of the Computational Fluid Dynamics (CFD) model validation was done against experimental data of three cases done by Jin et al. [1]. The model could simulate accurately contaminant mole fraction to the order of 10 Indoor air quality inside chemical laboratories subjected to gaseous contaminants was investigated numerically throughout the current research using Ansys Fluent 13. The lab is 4.8 m (L) * 4.3 m (W) * 2.73 m (H). The model was built and mesh was generated using Gambit 2.2.30 yielding around 1.4 million cells. To ensure the reliability of the Computational Fluid Dynamics (CFD) model validation was done against experimental data of three cases done by Jin et al. [1]. The model could simulate accurately contaminant mole fraction to the order of 10.

Experimentally Validated Computational Fluid Dynamics Model for Data Center With Active Tiles

2017 ◽  
Author(s):  
Jayati D. Athavale ◽  
Yogendra Joshi ◽  
Minami Yoda
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Computational Fluid Dynamics ◽  
Flow Rate ◽  
Data Center ◽  
Hot Spots ◽  
Cfd Model ◽  
Floor Tiles ◽  
Computational Fluid Dynamics Cfd ◽  
Plenum Pressure

This paper presents an experimentally validated room-level computational fluid dynamics (CFD) model for raised-floor data center configurations employing active tiles. Active tiles are perforated floor tiles with integrated fans, which increase the local volume flowrate by redistributing the cold air supplied by the computer room air conditioning (CRAC) unit to the under-floor plenum. In a previous study [1], experiments were conducted to explore the potential of active tiles for economically and efficiently eliminating hot spots in data center. Our results indicated that active tiles, as the actuators closest to the racks, can significantly and quickly impact the local distribution of cooling resources. They could therefore be used in an appropriate control framework to rapidly mitigate hot spots, and maintain local conditions in an energy-efficient manner. The numerical model of the data center room operates in an under-floor supply and ceiling return cooling configuration and consists of one cold aisle with 12 racks arranged on both sides and three CRAC units sited around the periphery of the room. The commercial computational fluid dynamics (CFD) software package Future Facilities 6SigmaDCX [2], which is specifically designed for data center simulation, is used to develop the model. First, a baseline model using only passive tiles was developed and experimental data were used to verify and calibrate plenum leakage for the room. Then a CFD model incorporating active tiles was developed for two configurations: (a) a single active tile and 9 passive tiles in the cold aisle; and (b) an aisle populated with 10 (i.e., all) active tiles. The active tiles are modeled as a combination of a grill, fan elements and flow blockages to closely mimic the actual active tile used in the experimental studies. The fan curve for the active tile fans is included in the model to account for changes in flow rate through the tiles in response to changes in plenum pressure. The model with active tiles is validated by comparing the flow rate through the floor tiles, relative plenum pressure and rack inlet temperatures for selected racks with the experimental measurements. The predictions from the CFD model are found to be in good agreement with the experimental data, with an average discrepancy between the measured and computed values for total flow rate and rack inlet temperature less than 4% and 1.7 °C, respectively. These validated models were then used to simulate steady state and transient scenarios following cooling failure. This physics-based and experimentally validated room-level model can be used to predict temperature and flow distributions in a data center using active tiles. These predictions can then be used to identify the optimal number and locations of active tiles to mitigate hot spots, without adversely affecting other parts of the data center.

scholarly journals Numerical Simulation and Comparison of Conventional and Sloped Solar Chimney Power Plants: The Case for Lanzhou

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Fei Cao ◽  
Huashan Li ◽  
Yang Zhang ◽  
Liang Zhao
Keyword(s):  
Fluid Dynamics ◽  
Numerical Simulation ◽  
Power Plant ◽  
Power Plants ◽  
Effective Pressure ◽  
Cfd Model ◽  
Solar Chimney ◽  
Computational Fluid Dynamics Cfd ◽  
Solar Chimney Power Plant

The solar chimney power plant (SCPP) generates updraft wind through the green house effect. In this paper, the performances of two SCPP styles, that is, the conventional solar chimney power plant (CSCPP) and the sloped solar chimney power plant (SSCPP), are compared through a numerical simulation. A simplified Computational Fluid Dynamics (CFD) model is built to predict the performances of the SCPP. The model is validated through a comparison with the reported results from the Manzanares prototype. The annual performances of the CSCPP and the SSCPP are compared by taking Lanzhou as a case study. Numerical results indicate that the SSCPP holds a higher efficiency and generates smoother power than those of the CSCPP, and the effective pressure in the SSCPP is relevant to both the chimney and the collector heights.

Validation of a Computationally Efficient Computational Fluid Dynamics (CFD) Model for Industrial Bubble Column Bioreactors

2014 ◽  
Vol 53 (37) ◽  
pp. 14526-14543 ◽  
Author(s):  
Dale D. McClure ◽  
Hannah Norris ◽  
John M. Kavanagh ◽  
David F. Fletcher ◽  
Geoffrey W. Barton
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Bubble Column ◽  
Cfd Model ◽  
Computationally Efficient ◽  
Computational Fluid Dynamics Cfd
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