Coupled 3-D CFD-DDPM Numerical Simulation of Turbulent Swirling Gas-Particle Flow Within Cyclone Suspension Preheater of Cement Kilns

Author(s):  
Eugen-Dan Cristea ◽  
Pierangelo Conti

The paper presents a three-dimensional (3-D), time-dependent Euler-Lagrange multiphase approach for high-fidelity numerical simulation of strongly swirling, turbulent, heavy dust-laden flows within large-sized cyclone separators, as components of the state-of-art suspension preheaters (SPH) of cement kilns. The case study evaluates the predictive performance of the coupled hybrid 3-D computational fluid dynamics–dense discrete phase model (CFD-DDPM) approach implemented into the commercial general purpose code ANSYS-Fluent R16.2, when applied to industrial cyclone collectors used to separate particles from gaseous streams. The gas (flue gases) flow is addressed numerically by using the traditional CFD methods to solve finite volume unsteady Reynolds-averaged Navier-Stokes (FV-URANS) equations. The multiphase turbulence is modeled by using an option of Reynolds stress model (RSM), namely dispersed turbulence model. The motion of the discrete (granular) phase is captured by DDPM methodology. The twin cyclones of SPH top-most stage have been analyzed extensively both for the overall pressure drop and global collection efficiency, and for the very complex multiphase flow patterns established inside this equipment. The numerical simulation results have been verified and partially validated against an available set of typical industrial measurements collected during a heat and mass balance (H&MB) of the cement kiln.

2018 ◽  
Vol 56 (3) ◽  
pp. 370
Author(s):  
Nguyen Van Thang ◽  
Ha Tien Vinh ◽  
Bui Dinh Tri ◽  
Nguyen Duy Trong

This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k-e turbulence model. The external airflow field of the simplified BMV M6 model with or without a wing is simulated. Several aerodynamic characteristics such as pressure distribution, velocity contours, velocity vectors, streamlines, turbulence kinetic energy and turbulence dissipation energy are analyzed in this study. The aerodynamic forces acting on the car model is calculated and compared with other authors.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Thandiwe Bongani Radebe ◽  
Zhongjie Huan ◽  
Jeffrey Baloyi

Purpose South Africa is the highest consumer of commercial energy per capita in Africa, ranking 16th in the world for primary energy consumption. It is also ranked among the bottom 50 of the 150 countries regarding energy efficiency. The cold chain is a large contributor through refrigerated transport vehicles. To comply with the changing climate regulations, cryogenic and eutectic systems are systems with great potential for small distance refrigerated transport. The purpose of this paper is to introduce eutectic system to medium distance refrigerated transport. Design/methodology/approach This study presents the potential use of Eutectic plates inside a medium refrigerated transport vehicle, by numerically investigating the characteristics of phase change material eutectic plates applied at low-temperature ranges. A physical model and a mathematical model for three-dimensional transient natural flow were developed as proposed by Xiaofeng and Zhang. Using the governing equation of mass, momentum and energy conservation, three Eutectic plate configurations were modeled and simulated in ANSYS Fluent for 5 h. Findings A uniform heat transfer and airflow condition inside a refrigerated compartment were predicted using the Reynolds stress model. The configuration with eutectic plates placed at the top and side showed great potential for the system functioning in the South African climate. Research limitations/implications Medium refrigerated transport vehicle. Originality/value This configuration had a high-temperature distribution across the compartment and promoted high air circulations, showing that it could be ideal for medium refrigerated transport vehicles delivering perishable foodstuffs or non-food goods.


Author(s):  
L. J. Lenke ◽  
H. Simon

The numerical simulation of the flow within a return channel is reported in this paper. The investigated return channel is typically to join the exit from one stage of a centrifugal machine to the inlet of the next stage. These channel covers the range of extremely low flow coefficients. Different 3-D calculations with two different turbulence models (low-Reynolds-number k-ϵ and explicit algebraic Reynolds stress model) at the design point and part load range show the strongly three-dimensional flow structure with secondary flows on hub and shroud of the deswirl vanes. There are also significant separations downstream of the 180°-bend at suction and pressure side of the vanes. The presented numerical results are compared with experimental data in different planes and at the vane contour. The results indicate small differences between the turbulence models in the prediction of losses, flow angles and separation behavior at design point. At off-design conditions the turbulence models begin to deviate notably in their prediction of separation.


2011 ◽  
Vol 383-390 ◽  
pp. 6530-6536 ◽  
Author(s):  
Man Yin Hu ◽  
Kai Che ◽  
Jing Zhang ◽  
Xiu Hong Wang

For the operation situation of the series-type electrostatic fabric filter precipitator, the deflectors in the inlet of the precipitator whose angle and spacing were changed to improve the air distribution characteristic and collection efficiency were assembled. The three-dimensional structural model of the series-type electrostatic fabric filter precipitator was built and meshed, then carried on the number simulation of air distribution characteristic with FLUENT. The simulation results show that when the deflector spacing is 0.7m and the incremental height is 0.15m the air distribution is more uniform. The numerical simulation result is reasonable and can be used as the reference to optimize the designing of electrostatic fabric filter precipitator.


Inventions ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 2
Author(s):  
Dimitra Douvi ◽  
Eleni Douvi ◽  
Dionissios P. Margaris

The aim of this study is the aerodynamic degradation of a three-bladed Horizontal Axis Wind Turbine (HAWT) under the influence of a hailstorm. The importance and originality of this study are that it explores the aerodynamic performance of an optimum wind turbine blade during a hailstorm, when hailstones and raindrops are present. The commercial Computational Fluid Dynamics (CFD) code ANSYS Fluent 16.0 was utilized for the simulation. The first step was the calculation of the optimum blade geometry characteristics for a three-bladed rotor, i.e., twist and chord length along the blade, by a user-friendly application. Afterwards, the three-dimensional blade and the flow field domain were designed and meshed appropriately. The rotary motion of the blades was accomplished by the application of the Moving Reference Frame Model and the simulation of hailstorm conditions by the Discrete Phase Model. The SST k–ω turbulence model was also added. The produced power of the wind turbine, operating in various environmental conditions, was estimated and discussed. Contours of pressure, hailstone and raindrop concentration and erosion rate, on both sides of the blade, are presented. Moreover, contours of velocity at various cross sections parallel to the rotor are demonstrated, to understand the effect of hailstorms on the wake behavior. The results suggest that the aerodynamic performance of a HAWT degrades due to impact and breakup of the particles on the blade.


2015 ◽  
Vol 789-790 ◽  
pp. 484-488 ◽  
Author(s):  
Fethi Saidi ◽  
Mohammed Aounallah ◽  
Mustapha Belkadi ◽  
Lahouari Adjlout ◽  
Omar Imine

The turbulent and thermal mixing in a vertically oriented T-junction is investigated numerically using ANSYS FLUENT software. By taking account the buoyancy forces, a steady state three-dimensional turbulent flow is considered with a Reynolds number of 0.4×105 at the cold inlet and 3.3×105 at the hot entrance. The k-ε standard model with standard wall function is chosen to provide closure for the Reynolds stress tensor. The numerical results presented in the form of velocity vectors field and contours of temperature distribution gave a good prediction of the dynamic and the thermal fields namely in the mixing region where a reversed flow is captured.


2020 ◽  
Vol 14 (2) ◽  
pp. 6610-6624 ◽  
Author(s):  
Om Parkash Verma ◽  
Arvind Kumar ◽  
Basant Singh Sikarwar

Transportation of solids with water as a carrier in the form of slurry through long length pipelines is widely used by many industries and power plants. The transportation of slurry through vertical pipeline is a challenging task and require modification to overcome the pressure loss and power consumption requirements. In this perspective, numerical simulation of three-dimensional horizontal slurry pipeline (HSPL) and vertical slurry pipeline (VSPL) carrying glass beads solid particulates of spherical diameter 440 µm and density 2,470 kg/m3 is carried out. The 3D computational model for horizontal and vertical slurry pipeline is developed for a pipe of 0.0549 m diameter and analyzed in available commercial software ANSYS Fluent 16. The simulation is conducted by using Eulerian multiphase model with RNG k-ɛ turbulence closure at solid concentration range 10 – 20% (by volume) for mean flow velocities ranging from 1-4 ms-1. It is found that the pressure drop rises for both HSPL and VSPL with escalation in mean flow velocity and solid concentration. The predicted pressure drop in VSPL is found to follow the same pattern as with HSPL but higher in magnitude for all chosen velocity and solid concentration range. The obtained results of predicted pressure drop in HSPL are validated with the available experimental data in the literature. A parametric study is conducted with the aim of visualizing and understanding the slurry flow behavior in HSPL and VSPL. Finally, the results of solid concentration contour, velocity contour, solid concentration profiles, velocity profiles and pressure drop are predicted for both the slurry pipelines.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Peng Chang ◽  
Tian Hu ◽  
Li Wang ◽  
Sen Chang ◽  
Tianjing Wang ◽  
...  

With the further development of oilfield, liquid-gas separation has become an essential problem. Cylindrical cyclone separators are popular in the industrial process due to the advantage that they are simple, compact, and inexpensive to manufacture. In this paper, a three-dimensional turbulence model including Reynolds stress model was established to describe the mixture flow field in the separator. Through the numerical simulation, the separation efficiency was investigated under different parameter cases such as separator length, gas phase outlet diameter, and inlet shape. It can be indicated from the simulation results that the separation efficiency decreases with the increase of the separator length, and the separation efficiency increases firstly and then decreases with the increase of the gas phase outlet diameter as well as the liquid phase outlet. Furthermore, the rectangular inlet is more suitable than the circular inlet with the separation efficiency changing from 66.45% to 79.04%. In the end, the optimal geometrical structure was presented with separation efficiency of 86.15%.


Sign in / Sign up

Export Citation Format

Share Document