scholarly journals Model of Thermal Plume above Cooking Gas Stove for Designing Ventilation

2019 ◽  
Vol 111 ◽  
pp. 01030
Author(s):  
Yuki Shimanuki ◽  
Takashi Kurabuchi ◽  
Yoshihiro Toriumi ◽  
Yasuhisa Asawa
Keyword(s):  
Vertical Direction ◽  
Thermal Plume ◽  
Cfd Analysis ◽  
Combustion Gas ◽  
Image Velocimetry ◽  
Pot Size ◽  
Measurement Results ◽  
Computational Fluid Dynamics Cfd ◽  
Analysis Models ◽  
Good Agreement

A model of the thermal plume above a cooking gas stove using computational fluid dynamics (CFD) analysis was studied to predict the heat and vapor released during cooking. The combustion gas released from the burner installed in the gas stove was considered as air in which thermal energy was adjusted so that the thermal plume above the gas stove could be simulated. Therefore, the model could predict the thermal plume above the gas stove based on the capacity of the burner and pot size. For validating the simulated flow fields, the results of the velocity distributions above the gas stove calculated using CFD analysis models were compared with the results of the velocity distributions measured with particle image velocimetry (PIV). In conclusion, the analysis results were in good agreement with the measurement results. However, the velocity in the vertical direction calculated using CFD above the center of the burner was higher than the velocity measured using PIV along the axis from the center of the burner.

The Hydrodynamics Studies on Loop Seal in CFBC Boiler Using CFD Analysis

2019 ◽  
Vol 15 (1) ◽  
Author(s):  
M. Vivekanandan ◽  
N. Anantharaman ◽  
M. Premalatha
Keyword(s):  
Pressure Drop ◽  
Circulating Fluidized Bed ◽  
Unit Length ◽  
Mechanical Valve ◽  
Sand Particle ◽  
Cfd Analysis ◽  
Solid Mass ◽  
Mass Fluxes ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement

Abstract In a circulating fluidized bed (CFB), the loop seal is an important component which recirculates the solids captured by the cyclone to the bottom of the riser and avoids the direct flow of gas from high-pressure riser to the low-pressure cyclone. Most of the CFBC systems employ a Non-Mechanical valve, and its function has been investigated by many researchers. In this work, the flow of solid particle within the loop seal has been studied elaborately, and various design and operating parameters of the loop seal were analyzed in detail using Computational Fluid Dynamics (CFD). The CFD study has handled a loop-seal of dimension 110 mm × 430 mm × 400 mm high. This analysis has been done with a 200 µm sand particle and it is checked for its flow ability through various sizes and by altering the L/H ratio for three solid mass fluxes and for three L/H ratios of loop seal. The rate of solid mass flux depends on the length of the horizontal passage connecting the recycle cycle compartment of the loop seal with the supply chamber and hence the solid flow rate and the pressure difference per unit length are directly proportional to the length of the chamber or passage. Hence, L/H ratio is taken as a driving variable for the optimum performance of loop seal. The CFD analysis results reveal that the aeration of the solid to be used within the loop-seal should be higher than the Minimum Fluidization velocity. Also, keeping the length of the horizontal passage constant and varying the height of the passage will reduce the pressure drop. The pressure drop across the horizontal passage decreases up to a certain L/H ratio after which it increases. By comparing the three L/H ratios, L/H ratio of 2.62 is having a lesser pressure drop for the three mass fluxes. L/H ratio of 2.62 is having a good fluidization phenomenon and also the flow from the recycle chamber is more in comparison to the other L/H ratios. Experimental data from the literature is in good agreement with the CFD results.

Piston-Lift Check Valve Flow Verification Using CFD

2018 ◽  
Author(s):  
Matthew Laney ◽  
Ronald Farrell
Keyword(s):  
Flow Characteristics ◽  
Check Valve ◽  
Valve Lift ◽  
Cfd Analysis ◽  
Test Results ◽  
Finite Element Software ◽  
Translational Movement ◽  
Wide Range ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement

Computational Fluid Dynamics (CFD) is increasingly being used as a reliable method for determining flow characteristics of a wide range of flow situations. This paper presents an extension of paper PVP2017-66269, “Check Valve Flow and Disk Lift Simulation Using CFD” [1], and utilizes some of the same concepts to characterize flow through piston-lift check valves. The previous example considered a swing check valve involving rotational movement; this example considers a vertical lift piston check valve involving translational movement. Specifically, CFD was used to determine valve flow coefficients (CV) as a function of disk lift position as well as to determine the flow rate required to achieve full open or predict intermediate disk lift positions. The CFX application, which is part of the ANSYS suite of finite element software, was used to determine the flow characteristics. As presented in PVP2017-66269, balancing flow-induced forces on the check element and considering the disk assembly weight, the valve lift behavior can be predicted. Results from the CFX analysis were compared to recent test results of a skirted disk-piston check valve and previous test results of a standard disk-piston check valve. The results showed good agreement in most cases. This validates that flow characteristics across valves with different types of check elements at different disk lift positions can be reliably predicted using CFD analysis. It is important to note that while the test results and CFD analysis showed good agreement, it was vital that actual testing be performed in order to validate the approach. This follows the recommendation outlined in the previous paper.

Model Testing and CFD Analysis of 2D Profiles Towards Offshore Applications

2013 ◽  
Author(s):  
Lucas do Vale Machado ◽  
Antonio Carlos Fernandes ◽  
Gustavo César Rachid Bodstein
Keyword(s):  
Experimental Data ◽  
Experimental Measurements ◽  
Cfd Analysis ◽  
Two Dimensional ◽  
Reference Simulation ◽  
Sst Turbulence Model ◽  
Computational Fluid Dynamics Cfd ◽  
Simulation Results ◽  
Naca 0015 ◽  
Good Agreement

In this paper we present numerical and experimental work motivated by the study of a rudder profile with significant levels of lift that provides better performance for the maneuvering and stabilization of a ship. This is the so-called Schilling profile. The analysis of the two-dimensional subsonic steady flow over four profiles was carried out using computational fluid dynamics (CFD) tools with a κ-ω SST turbulence model. We consider three Schilling profiles with different thicknesses and the classical NACA 0015 profile, taken as a reference. Simulation results were compared to our experimental measurements at various angles of attack and two orders of magnitude of the Reynolds number, 5.45 × 104 and 1.09 × 105. The numerical results show general good agreement with experimental data and highlight the distinct behavior of Schilling profile.

CFD Analysis of Gear Windage Losses: Validation and Parametric Aerodynamic Studies

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Matthew J. Hill ◽  
Robert F. Kunz ◽  
Richard B. Medvitz ◽  
Robert F. Handschuh ◽  
Lyle N. Long ◽  
...  
Keyword(s):  
Experimental Data ◽  
Spur Gear ◽  
Mitigation Strategies ◽  
Test Facility ◽  
Cfd Analysis ◽  
Physical Mechanisms ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Method ◽  
Cfd Analyses ◽  
Good Agreement

A computational fluid dynamics (CFD) method has been applied to gear configurations with and without shrouding. The goals of this work have been to validate the numerical and modeling approaches used for these applications and to develop physical understanding of the aerodynamics of gear windage loss. Several spur gear geometries are considered, for which experimental data are available. Various canonical shrouding configurations and free spinning (no shroud) cases are studied. Comparisons are made with experimental data from open literature, and data recently obtained in the NASA Glenn Research Center Gear Windage Test Facility, Cleveland, OH. The results show good agreement with the experiment. The parametric shroud configuration studies carried out in the Glenn experiments and the CFD analyses elucidate the physical mechanisms of windage losses as well as mitigation strategies due to shrouding and newly proposed tooth contour modifications.

scholarly journals Effect of Aft Rotor on the Inter-Rotor Flow of an Open Rotor Propulsion System

2016 ◽  
Vol 139 (4) ◽  
Author(s):  
Paul E. Slaboch ◽  
David B. Stephens ◽  
Dale E. Van Zante ◽  
Mark P. Wernet
Keyword(s):  
Substantial Effect ◽  
Tip Vortex ◽  
Image Processing Algorithm ◽  
Cfd Simulations ◽  
Rotor Position ◽  
Image Velocimetry ◽  
Open Rotor ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement ◽  
Rotor Flow

The effects of the aft rotor on the inter-rotor flow field of an open rotor propulsion rig (ORPR) were examined. A particle image velocimetry (PIV) dataset that was acquired phase locked to the front rotor position has been phase averaged based on the relative phase angle between the forward and aft rotors. The aft rotor phase was determined by feature tracking in raw PIV images through an image-processing algorithm. The effects of the aft rotor potential field on the inter-rotor flow were analyzed and shown to be in reasonably good agreement with computational fluid dynamics (CFD) simulations. The aft rotor position was shown to have a significant upstream effect, with implications for front rotor interaction noise. It was found that the aft rotor had no substantial effect on the position of the forward rotor tip vortex but did have a small effect on the circulation strength of the vortex when the rotors were highly loaded.

scholarly journals Experimental Investigation of the Effect of Ice Blockage on Propeller Hydrodynamic Performance

2019 ◽  
Vol 2019 ◽  
pp. 1-19
Author(s):  
Chun-Yu Guo ◽  
Pei Xu ◽  
Chao Wang ◽  
Wei-Peng Xiong
Keyword(s):  
Transverse Direction ◽  
Particle Image ◽  
Fluid Velocity ◽  
Vertical Direction ◽  
Wake Flow ◽  
Hydrodynamic Performance ◽  
Propeller Wake ◽  
Image Velocimetry ◽  
Measurement Results ◽  
Thrust And Torque

This experimental study investigates the influence of different sizes, quantities, and axial positions of model ice on propeller hydrodynamic performance. We used particle image velocimetry measurements to analyze the characteristics of the propeller wake flow field. The measurement results show that ice blockage leads to an increase in propeller thrust, torque, and efficiency. The smaller the advance coefficient of the propeller is, the smaller the influence of model ice on propeller blockage is. As the model ice becomes thicker and the thrust and efficiency of the propeller increase, the propeller torque is smaller for low advance coefficient and higher for high advance coefficient. The wider the model ice is, the larger the thrust and torque of the propeller are. Once the model ice width exceeds the propeller diameter, the change in its width has no effect on propeller efficiency. When the propeller is blocked with model ice, the fluid velocity in the wake flow reduces in the inflow direction, and the increase in fluid velocity in the horizontal transverse direction and variation of fluid velocity in the vertical direction are related to the model ice width.

Comparison Between PIV Results and CFD Simulations of Air Flows in a Thin Electronics Casing Model

2012 ◽  
Author(s):  
Masaru Ishizuka ◽  
Tomoyuki Hatakeyama ◽  
Risako Kibushi ◽  
Yasushi Nishino ◽  
Shinji Nakagawa
Keyword(s):  
Fluid Dynamics ◽  
Particle Image Velocimetry ◽  
Particle Image ◽  
Electronic Equipment ◽  
Cfd Simulations ◽  
Cooling Performance ◽  
Piv Measurement ◽  
Image Velocimetry ◽  
Measurement Results ◽  
Good Agreement

The aim of this study was to acquire benchmark test data for simulating computational fluid dynamics in thin electronic equipment. Flow in the model of thin electronic equipment was measured by using particle image velocimetry PIV). Dummy components were placed in the model and their configurations altered. The temperature rise of a heat source in the model was also measured and the cooling performance examined. The PIV measurement results revealed the changes in flow with changes in the configuration of the components. Comparison of the experimental results with numerical results showed good agreement in terms of the overall velocity field.

Multiphase CFD Analysis of a Subsea Intervention System

2015 ◽  
Author(s):  
Elham Maghsoudi ◽  
Uday Godse ◽  
Alistair Gill
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Large Scale ◽  
Cfd Analysis ◽  
Cfd Models ◽  
System A ◽  
Mixing Behavior ◽  
Computational Fluid Dynamics Cfd ◽  
2D And 3D ◽  
Good Agreement

In this study, a computational fluid dynamics (CFD) analysis was conducted to evaluate a new design of an intervention system. A multiphase analysis was performed to understand the mixing characteristics as the cement is pumped into the well and the degree to which the cement could be contaminated with spacer fluid. A transient multiphase analysis was conducted to examine the flow and the mixing behavior through the various sections of the intervention system. A combination of 2D and 3D CFD models was used, depending upon the geometry in each section. The results indicated that the intervention system operates efficiently without diluting the cement. Non-Newtonian methods used in CFD were validated using available theoretical and experimental data. In a large-scale yard test, good agreement was obtained for resin and water; however, cement did not show good agreement as the flow rate increased over 1 bbl/min.

scholarly journals Effect of Aft Rotor on the Inter-Rotor Flow of an Open Rotor Propulsion System

2016 ◽  
Author(s):  
Paul E. Slaboch ◽  
David B. Stephens ◽  
Dale E. Van Zante
Keyword(s):  
Substantial Effect ◽  
Tip Vortex ◽  
Image Processing Algorithm ◽  
Cfd Simulations ◽  
Rotor Position ◽  
Image Velocimetry ◽  
Open Rotor ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement ◽  
Rotor Flow

The effects of the aft rotor on the inter-rotor flow field of an open rotor propulsion rig were examined. A Particle Image Velocimetry (PIV) dataset that was acquired phase locked to the front rotor position has been phase averaged based on the relative phase angle between the forward and aft rotors. The aft rotor phase was determined by feature tracking in raw PIV images through an image processing algorithm. The effects of the aft rotor potential field on the inter-rotor flow were analyzed and shown to be in reasonably good agreement with Computational Fluid Dynamics (CFD) simulations. The aft rotor position was shown to have a significant upstream effect, with implications for front rotor interaction noise. It was found that the aft rotor had no substantial effect on the position of the forward rotor tip vortex but did have a small effect on the circulation strength of the vortex when the rotors were highly loaded.

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