Study on Pressure Drop and Center Line Velocity Distribution Across Cosine Shaped Stenotic Model

2009 ◽  
Vol 36 (4) ◽  
pp. 319-342
Author(s):  
Moloy Kumar Banerjee ◽  
Ranjan Ganguly ◽  
Amitava Datta
Keyword(s):  
Pressure Drop ◽  
Velocity Distribution ◽  
Center Line

Accuracy Investigation of Active Flow Control Using Synthetic Jets

2015 ◽  
Vol 741 ◽  
pp. 475-480
Author(s):  
Na Gao ◽  
Chen Pu ◽  
Bao Chen
Keyword(s):  
Flow Control ◽  
Velocity Distribution ◽  
Active Flow Control ◽  
Flow Fields ◽  
Synthetic Jet ◽  
Synthetic Jets ◽  
Experimental Results ◽  
Center Line ◽  
Mean Velocity ◽  
The Mean

2nd order implicit format is implemented in the Navier-Stokes code to deal with instantaneous item unsteady flows. Three simulations are made to testify the method on flow control. First, the external flow fields of synthetic jets are simulated, the mean velocity on the center line, the jet width and velocity distribution are compared well with experimental results. Secondly, the flow fields of synthetic jet in a crossflow are simulated, orifice slot, the mean velocity on the center line and velocity distribution are compared well with experimental results. Finally, the flow control experiments on separation of airfoil are simulated, control methods include steady suction and synthetic jets. Both methods show their ability to favorably effect the flow separation, shortening the length of separation bubble and improving the pressure levels in separation areas in different degrees.

scholarly journals Effects of Pitot Tube Inserted and Those of Dust Loading on Pressure Drop and Velocity Distribution in Cyclone

1956 ◽  
Vol 20 (4) ◽  
pp. 172-183
Author(s):  
Takeo Yano ◽  
Yoshiyuki Kitaura ◽  
Yukio Nakako ◽  
Tadaaki Yamaguchi ◽  
Shunpei Uchiyama
Keyword(s):  
Pressure Drop ◽  
Velocity Distribution ◽  
Pitot Tube ◽  
Dust Loading

CFD Prediction of Gas-Liquid Separation Efficiency of Geothermal Steam-Water Cyclone Separator Using a Verified Turbulence Model

2017 ◽  
Author(s):  
Xidong Hu ◽  
Shaoxiang Qian ◽  
Kaori Yamauchi ◽  
Haruo Okochi
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Velocity Distribution ◽  
Flow Velocity ◽  
Separation Efficiency ◽  
Turbulence Models ◽  
Phase Flow ◽  
Cyclone Separator ◽  
Steam Quality ◽  
Rsm Model

The present paper aims to predict the separation efficiency and pressure drop of a vertical geothermal cyclone type separator using CFD (Computational Fluid Dynamics) simulations, for optimizing the design of such separator. A benchmark study was firstly performed for a single phase flow in a Stairmand design cyclone using four different turbulence models, in order to verify the prediction accuracy of flow velocity distribution by comparison with experimental data in literature. The investigated turbulence models include (1) Renormalization Group (RNG) k-ε, (2) Realizable k-ε, (3) Reynolds stress turbulence model (RSM) and (4) Large eddy simulation (LES). Results show that RNG k-ε and Realizable k-ε models are not capable of reproducing the experimental data while the RSM and LES models reproduce the flow velocity distribution very well. Then, CFD simulations of two-phase flow in a steam-water cyclone separator were carried out for different stream inlet velocities applying the RSM model. This is based on the consideration that steady state analysis can be done for the RSM model, and however, transient analysis is needed for the LES model, and hence, more expensive and time-consuming for engineering applications. The CFD results for outlet steam quality and pressure drop were obtained under different stream inlet velocities. The separation efficiency and outlet steam quality decreases a little when the inlet velocity increases from 34.5m/s to 72m/s. However, the outlet steam quality predicted in the present CFD analysis is close to that of Lazalde-Crabtree.

Study on Appropriate Diameter of Centrifugal Fan Surrounded by Heat Exchanger in Air Conditioner

2017 ◽  
Author(s):  
Daiwa Sato ◽  
T. Iwase ◽  
J. Xue ◽  
K. Tsuchihashi ◽  
H. Obara ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Heat Exchange ◽  
Standard Deviation ◽  
Pressure Drop ◽  
Velocity Distribution ◽  
Flow Distribution ◽  
Centrifugal Fan ◽  
Air Conditioner ◽  
Air Conditioners ◽  
Fan Performance

To meet the demand for energy-saving air conditioners, the pressure drop must be reduced and the air velocity distribution of the heat exchanger made uniform to improve the performance of both the fan and the heat exchange cycle. To investigate the effect of the fan on the pressure drop and the velocity distribution, we changed the fan diameter and fixed the shape of the heat exchanger. First, we investigated the fan by comparing the total pressure efficiency when the fan was mounted in an indoor unit and unmounted as a standalone fan. We found that the mounted fan performed worse than the standalone fan. The difference between these conditions was whether the heat exchanger was around the fan. Next, to determine the appropriate diameter, the performance of the mounted fan was evaluated by measuring its efficiency and the fan power. The diameter with the highest efficiency differed from the diameter with the lowest fan power. Because of this, the fan performance was strongly affected by the heat exchanger and the vortex. When the standard deviation of the air flow distribution in the heat exchanger was evaluated, the diameter with the lowest standard deviation was the same as the diameter with the lowest fan power. Since the standard deviation needs to be reduced to improve the performance of both the fan and the heat exchange cycle, the mounting conditions need to be considered to determine the fan shape. Thus, the flow field around the fan was visualized, and the velocity distributions for the investigated diameters were compared. We found the distance between the fan and the heat exchanger was an important factor determining the performance. A fan with the most appropriate diameter was prototyped to evaluate the fan performance. Results revealed it used 3% less power than a standard-diameter fan.

Effects of Surface Roughness on Single Phase Fluid Flow and Heat Transfer Characteristics in Microchannels

2009 ◽  
Author(s):  
Jinli Lu ◽  
Yingli Hao
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Pressure Drop ◽  
Velocity Distribution ◽  
Shape Factor ◽  
Single Phase ◽  
Peak Position ◽  
Centerline Velocity ◽  
Heat Transfer Characteristics ◽  
Flow And Heat Transfer

A two dimensional numerical simulation is conducted to investigate the flow and heat transfer characteristics of single phase liquid laminar flow through rough microchannels. The wall roughness is simulated in a series of cases with rectangular, triangular and trapezoidal elements, respectively. Shape factor and peak position have been used to analyze the influence of roughness elements on centerline velocity distribution, pressure drop and Nusselt number. It is found that the shape factor has a significant effect on the centerline velocity distribution, pressure drop and Nusselt number. It is also found that, for a given shape factor, the effect of peak position on pressure drop is strongly than centerline velocity distribution and heat transfer. In addition, for all considered roughness element shapes, the rectangular element displays a poor heat transfer and large pressure drop.

Experimental Study on Internal Flow Field of Wet Desulphurization Tower

2011 ◽  
Vol 354-355 ◽  
pp. 137-144
Author(s):  
Jing Zhu ◽  
Qi Xu ◽  
Li Ping Zhang
Keyword(s):  
Experimental Study ◽  
Pressure Drop ◽  
Velocity Distribution ◽  
Flue Gas ◽  
Velocity Ratio ◽  
Internal Flow ◽  
Liquid Droplets ◽  
Gas Velocity ◽  
Entrance Angle ◽  
Inlet Angle

In order to study the flue gas velocity distribution and pressure drop characteristics inside wet desulfurization Tower, experimental study has been carried out. Flow model is built with geometric scale of 1 / 12 , flue gas velocity ratio of 1 / 1 and different gas entrance angle as 12°and 7°. Experiment result shows that Spray liquid droplets made gas more evenly; The evenness of gas velocity distribution is very poor with very low gas load (<35%);The pressure drop in tower increases with increase of sprayer and increases with increase of gas load; The evenness of gas velocity distribution becomes poor and the pressure drop increases when gas inlet angle changes from 12°to 7°.

scholarly journals Steady flow of high-paraffin bituminous binder in cylindrical tube in terms of Herschel – Bulkley fluid

2021 ◽  
Vol 23 (4) ◽  
pp. 79-99
Author(s):  
Oleg V. Matvienko ◽  
Alyona E. Litvinova
Keyword(s):  
Fluid Flow ◽  
Pressure Drop ◽  
Velocity Distribution ◽  
Radial Velocity ◽  
Steady Flow ◽  
Hydraulic Resistance ◽  
Flow Rate ◽  
Effective Viscosity ◽  
Cylindrical Tube ◽  
Fluid Flow Rate

This paper deals with the flow of bitumen binder in a cylindrical tube described by the Hershel-Bulkley fluid. The dependence is suggested for the fluid flow rate and the pressure drop. Dependences are also determined for the radial velocity distribution and effective viscosity. It is found that at a low pressure drop, the non-Newtonian properties of the medium lead to a significant hydraulic resistance due to the internal structure. With an increase in the pressure drop, the hydraulic resistance of the flow decreases.

Sign in / Sign up

Export Citation Format

Share Document