Numerical Simulation of Flow Field in a Quench Oil Tower

2007 ◽  
Author(s):  
Shuihua Zheng ◽  
Shengchang Zhang ◽  
Zengliang Gao
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Flow Field ◽  
Petrochemical Industry ◽  
Flow Distribution ◽  
Discrete Phase Model ◽  
Wide Range ◽  
Modification Method ◽  
Discrete Phase ◽  
Cfd Method

Towers are applied in the wide range of the petrochemical industry. The flow condition and the temperature distribution in the tower are the focus of the people’s attention, which would affect function of the tower and could result in unstable operation of the tower. In this paper, the flow field in a quench oil tower is simulated based on CFD method. The DPM (Discrete Phase Model) is used to calculate and analyze flow distribution and heat transfer between gas and liquid. The numerical results such as temperature and velocity distributions below lower tray in tower are obtained. According to CFD results, modification method of improving the flow distribution is proposed.

scholarly journals Numerical Simulation of Haze-Fog Particle Dispersion in the Typical Urban Community by Using Discrete Phase Model

Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 381
Author(s):  
Hongbo Zhu ◽  
Jie Su ◽  
Xuesen Wei ◽  
Zhaolong Han ◽  
Dai Zhou ◽  
...  
Keyword(s):  
Flow Distribution ◽  
Spatial Arrangement ◽  
Particle Dispersion ◽  
Phase Model ◽  
Wind Flow ◽  
Detached Eddy Simulation ◽  
Discrete Phase Model ◽  
Delayed Detached Eddy Simulation ◽  
Discrete Phase ◽  
Cfd Method

The haze-fog particle dispersion in urban communities will cause serious health and environmental problems, which has aroused society attention. The aim of the present investigation is to reveal the underlying mechanisms of haze-fog particle dispersion via Computational Fluid Dynamics (CFD) method, and then to provide a groundwork for the optimal spatial arrangement of urban architecture. The Delayed Detached-eddy Simulation turbulence model (DDES) and Discrete Phase Model (DPM) are utilized to investigate the wind flow distribution and the particle dispersion around the building group. The numerical results show that the particle dispersion is dominated by the incoming wind flow, the layout of architectural space and the type and distribution of vortex. The ‘single body’ wake pattern and the vortex impingement wake pattern are identified in the wind flow field, which have different effects on the distribution of haze-fog particle. The cavity formed by the layout of the building group induces primary vortex and secondary vortex, which will make it more difficult for the particles entering the square cavity to flow out. Moreover, the concentration of the particle in the rear of the buildings is relatively low due the effect of attached vortices.

Numerical Simulation for Two-Phase Flow Field of FGD Scrubber in Ship

2013 ◽  
Vol 739 ◽  
pp. 450-453
Author(s):  
Yong Zheng Gu ◽  
Zhi Feng Dong ◽  
Quan Jin Kuang ◽  
Jie Liu ◽  
Yu Zhao Zhang
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Optimization Design ◽  
Two Phase Flow ◽  
Three Dimensional ◽  
Simple Algorithm ◽  
Phase Flow ◽  
Discrete Phase Model ◽  
Two Phase ◽  
Discrete Phase

Discrete phase model was used for three-dimensional numerical simulation of two-phase flow in the ship FGD scrubber. The κ-ε model and SIMPLE algorithm were adopted in the calculation. The results showed that adding porous baffles improved the distribution of flow field in the scrubber. The gas velocity in the scrubber became uniformity and the flue gas resistance decreased when the sprays worked. Under the action of the spray, the differential pressure of spray area changed greatly. The simulation plays a certain role in guiding the structural optimization design of scrubber.

scholarly journals Effects of Blade Parameters on the Flow Field and Classification Performance of the Vertical Roller Mill via Numerical Investigations

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Chang Liu ◽  
Zuobing Chen ◽  
Weili Zhang ◽  
Chenggang Yang ◽  
Ya Mao ◽  
...  
Keyword(s):  
Flow Field ◽  
Pressure Difference ◽  
Continuous Phase ◽  
Classification Performance ◽  
Field Analysis ◽  
Discrete Phase Model ◽  
Roller Mill ◽  
Discrete Phase ◽  
Vertical Roller ◽  
Classification Efficiency

The vertical roller mill is an important crushing and grading screening device widely used in many industries. Its classification efficiency and the pressure difference determine the entire producing capacity and power consumption, respectively, which makes them the two key indicators describing the mill performance. Based on the DPM (Discrete Phase Model) and continuous phase coupling model, the flow field characteristics in the vertical roller mill including the velocity and pressure fields and the discrete phase distributions had been analyzed. The influence of blade parameters like the shape, number, and rotating speed on the flow field and classification performance had also been comprehensively explored. The numerical simulations showed that there are vortices in many zones in the mill and the blades are of great significance to the mill performance. The blade IV not only results in high classification efficiency but also reduces effectively the pressure difference in the separator and also the whole machine. The conclusions of the flow field analysis and the blade effects on the classification efficiency and the pressure difference could guide designing and optimizing the equipment structure and the milling process, which is of great importance to obtain better overall performance of the vertical roller mill.

Hydraulic Characteristics of the New Type Bulb Turbine With Micro-Head

2013 ◽  
Author(s):  
Lingyu Li ◽  
Yuan Zheng ◽  
Daqing Zhou ◽  
Zihao Mi
Keyword(s):  
Numerical Simulation ◽  
Cfd Simulation ◽  
Guide Vane ◽  
Three Dimensional ◽  
Flow Distribution ◽  
Three Dimensions ◽  
Guide Vanes ◽  
Runner Blade ◽  
Cfd Method ◽  
Bulb Turbine

The head of low-head hydropower stations is generally higher than 2.5m in the world, while micro-head hydropower resources which head is less than 2.5m are also very rich. In the paper, three-dimensional CFD method has been used to simulate flow passage of the micro-head bulb turbine. The design head and unit flow of the turbine was 1m and 3m3/s respectively. With the numerical simulation, the bulb turbine is researched by analyzing external characteristics of the bulb turbine, flow distribution before the runner, pressure distribution of the runner blade surface, and flow distribution of the outlet conduit under three different schemes. The turbine in second scheme was test by manufactured into a physical model. According to the results of numerical simulation and model test, bulb turbine with no guide vane in second scheme has simpler structure, lower cost, and better flow capacity than first scheme, which has traditional multi-guide vanes. Meanwhile, efficiency of second scheme has just little decrease. The results of three dimensions CFD simulation and test results agree well in second scheme, and higher efficiency is up to 77% which has a wider area with the head of 1m. The curved supports in third scheme are combined guide vanes to the fixed supports based on 2nd scheme. By the water circulations flowing along the curved supports which improve energy transformation ability of the runner, the efficiency of the turbine in third scheme is up to 82.6%. Third scheme, which has simpler structure and best performance, is appropriate for the development and utilization of micro-head hydropower resources in plains and oceans.

Numerical simulation of circulating fluidized bed oxy-fuel combustion with Dense Discrete Phase Model

2019 ◽  
Vol 195 ◽  
pp. 106129 ◽  
Author(s):  
Ying Wu ◽  
Daoyin Liu ◽  
Dong Zheng ◽  
Jiliang Ma ◽  
Lunbo Duan ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Fluidized Bed ◽  
Circulating Fluidized Bed ◽  
Fuel Combustion ◽  
Phase Model ◽  
Discrete Phase Model ◽  
Discrete Phase

Numerical Simulation and Experiment on the Electrolyte Flow Distribution for All Vanadium Redox Flow Battery

2011 ◽  
Vol 236-238 ◽  
pp. 604-607 ◽  
Author(s):  
Jin Qing Chen ◽  
Bao Guo Wang ◽  
Hong Ling Lv
Keyword(s):  
Flow Field ◽  
Flow Distribution ◽  
Parallel Flow ◽  
Vanadium Redox Flow Battery ◽  
Redox Flow Battery ◽  
Flow Battery ◽  
Electrolyte Flow ◽  
Cfd Method ◽  
The Impact ◽  
Vanadium Redox

The electrolyte flow states of all vanadium redox flow battery (VRB) have a direct effect on the battery performance and life. To reveal the electrolyte distribution in the battery, the computation fluid dynamics (CFD) method was used to simulate a parallel flow field. A hydraulics experiment and a battery performance experiment were carried out to confirm the simulated results. The results show that the predicted information agreed well with the experimental results. The electrolyte has a concentrated distribution in the central region of the parallel flow field and the disturbed flow and then vortex flow areas mainly appear in the inlet and outlet regions. The higher flux of electrolyte is helpful to uniform the distributions and to reduce the impact of flow irregularity on the battery performance. The battery with the flow field generates a power density of 15.9 mW∙cm-2, and the coulombic, voltage and energy efficiency is up to 90.5%, 74.0% and 67.2% at a current density of 20 mA·cm-2.

Numerical Simulation of Fractal Tree-Shaped Flow Field Structures in PEMFC

2012 ◽  
Vol 151 ◽  
pp. 32-35 ◽  
Author(s):  
Jin Hua Dong ◽  
Shun Fang Liu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Mass Transfer ◽  
Flow Field ◽  
Proton Exchange Membrane ◽  
Plant Root ◽  
Fractal Theory ◽  
Bipolar Plate ◽  
Field Structure ◽  
Proton Exchange

The fractal tree-shaped structure such as tree, plant root, leaves, animal lung and so on is universal and unique in nature. These structures possess the symmetric micro-channel distributions and the efficient transport characteristics. They are considered to be an optimal network channel of mass transfer and heat transfer. The mass transfer and heat transfer feature of bipolar plate in proton exchange membrane fuel cell (PEMFC) is similar with animal lungs and leaves. In this paper, fractal theory is used to study tree-shaped flow field structure of bipolar plate in PEMFC. It is demonstrated by numerical simulation that fractal tree-shaped flow field structure can provide substantially flow-field distribution, current density and heat transfer compared to the traditional flow field structure.

Numerical Simulation of the Temperature Field and the Flow Field Inside the Domestic Cooling and Heating Unit’s Water Tank

2012 ◽  
Author(s):  
Chao Zhu ◽  
Mo Yang ◽  
Yuwen Zhang ◽  
Jinlong Wang
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Temperature Distribution ◽  
Flow Field ◽  
Water Temperature ◽  
Waste Heat ◽  
Flow Distribution ◽  
Water Tank ◽  
Heating Unit ◽  
Speed Up

A water tank of the domestic cooling and heating unit, which has a helix coil, is used to recover the waste heat of the unit. The temperature field and the flow field in the water tank have great effects on the variation of the water temperature in it. In order to obtain the temperature distribution, the flow distribution and the influencing factors, and then obtain the changing situation of the water temperature, the temperature field and the flow field of the water tank are simulated by using Fluent. The results showed that the water temperature will change with different coil decorate. The numerical model which is created by Fluent is appropriate and could be used to improve the layout of the coil in the water tank and speed up heating.

scholarly journals Assessment of Lagrangian Modeling of Particle Motion in a Spiral Microchannel for Inertial Microfluidics

Micromachines ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 433 ◽  
Author(s):  
Reza Rasooli ◽  
Barbaros Çetin
Keyword(s):  
Flow Field ◽  
Computational Model ◽  
Free Particle ◽  
Discrete Phase Model ◽  
Inertial Microfluidics ◽  
Aspect Ratios ◽  
Lagrangian Modeling ◽  
Discrete Phase ◽  
Spiral Microchannel ◽  
Spiral Channel

Inertial microfluidics is a promising tool for a label-free particle manipulation for microfluidics technology. It can be utilized for particle separation based on size and shape, as well as focusing of particles. Prediction of particles’ trajectories is essential for the design of inertial microfluidic devices. At this point, numerical modeling is an important tool to understand the underlying physics and assess the performance of devices. A Monte Carlo-type computational model based on a Lagrangian discrete phase model is developed to simulate the particle trajectories in a spiral microchannel for inertial microfluidics. The continuous phase (flow field) is solved without the presence of a discrete phase (particles) using COMSOL Multi-physics. Once the flow field is obtained, the trajectory of particles is determined in the post-processing step via the COMSOL-MATLAB interface. To resemble the operation condition of the device, the random inlet position of the particles, many particles are simulated with random initial locations from the inlet of the microchannel. The applicability of different models for the inertial forces is discussed. The computational model is verified with experimental results from the literature. Different cases in a spiral channel with aspect ratios of 2.0 and 9.0 are simulated. The simulation results for the spiral channel with an aspect ratio of 9.0 are compared against the experimental data. The results reveal that despite certain limitations of our model, the current computational model satisfactorily predicts the location and the width of the focusing streams.

Sign in / Sign up

Export Citation Format

Share Document