Application of CFD modelling at a full-scale ozonation plant for the removal of micropollutants from secondary effluent

2013 ◽  
Vol 68 (6) ◽  
pp. 1336-1344 ◽  
Author(s):  
M. Launer ◽  
S. Lyko ◽  
H. Fahlenkamp ◽  
P. Jagemann ◽  
P. Ehrhard
Keyword(s):  
Full Scale ◽  
Secondary Effluent ◽  
Cfd Model ◽  
Process Data ◽  
Cfd Modelling ◽  
Reaction Rate Constants ◽  
Batch Tests ◽  
Reactor Geometry ◽  
Computational Fluid Dynamics Cfd ◽  
The Given

Since November 2009, Germany's first full-scale ozonation plant for tertiary treatment of secondary effluent is in continuous operation. A kinetic model was developed and combined with the commercial computational fluid dynamics (CFD) software ANSYS® CFX® to simulate the removal of micropollutants from secondary effluents. Input data like reaction rate constants and initial concentrations of bulk components of the effluent organic matter (EfOM) were derived from experimental batch tests. Additionally, well-known correlations for the mass transfer were implemented into the simulation model. The CFD model was calibrated and validated by full-scale process data and by analytical measurements for micropollutants. The results show a good consistency of simulated values and measured data. Therewith, the validated CFD model described in this study proved to be suited for the application of secondary effluent ozonation. By implementing site-specific ozone exposition and the given reactor geometry the described CFD model can be easily adopted for similar applications.

Hydrodynamic evaluation of a full-scale facultative pond by computational fluid dynamics (CFD) and field measurements

2014 ◽  
Vol 70 (3) ◽  
pp. 569-575 ◽  
Author(s):  
Ricardo Gomes Passos ◽  
Marcos von Sperling ◽  
Thiago Bressani Ribeiro
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Short Circuit ◽  
Field Measurements ◽  
Tracer Test ◽  
Full Scale ◽  
Cfd Model ◽  
Cfd Modelling ◽  
Hydraulic Behaviour ◽  
Computational Fluid Dynamics Cfd

Knowledge of the hydraulic behaviour is very important in the characterization of a stabilization pond, since pond hydrodynamics plays a fundamental role in treatment efficiency. An advanced hydrodynamics characterization may be achieved by carrying out measurements with tracers, dyes and drogues or using mathematical simulation employing computational fluid dynamics (CFD). The current study involved experimental determinations and mathematical simulations of a full-scale facultative pond in Brazil. A 3D CFD model showed major flow lines, degree of dispersion, dead zones and short circuit regions in the pond. Drogue tracking, wind measurements and dye dispersion were also used in order to obtain information about the actual flow in the pond and as a means of assessing the performance of the CFD model. The drogue, designed and built as part of this research, and which included a geographical positioning system (GPS), presented very satisfactory results. The CFD modelling has proven to be very useful in the evaluation of the hydrodynamic conditions of the facultative pond. A virtual tracer test allowed an estimation of the real mean hydraulic retention time and mixing conditions in the pond. The computational model in CFD corresponded well to what was verified in the field.

CFD Modelling of Liquid Poison Injection in ACR-1000 Shutdown System

2008 ◽  
Author(s):  
F. Song ◽  
R. Noghrehkar ◽  
K. F. Hau
Keyword(s):  
Reactor Core ◽  
Basic Design ◽  
Nozzle Design ◽  
Cfd Model ◽  
Cfd Modelling ◽  
Type Reactor ◽  
Ansys Cfx ◽  
Liquid Injection ◽  
Computational Fluid Dynamics Cfd ◽  
Reactor Shutdown

The Liquid Injection Shutdown System (LISS) is a safety system in the CANDU™-type reactor to provide rapid reactor shutdown by automatically injecting a neutron absorbing liquid (“poison”), via injection nozzles, into the moderator in the calandria. The poison distribution in the moderator plays a significant role in the shutdown performance. The Advanced CANDU Reactor (ACR-1000™) is a Generation III+ type reactor as an evolutionary extension of the proven CANDU-6 reactor. The basic design concept of the CANDU-6 LISS is adopted for the ACR-1000. The injection nozzle design has been modified to suit the ACR-1000 reactor core configuration. In this study, a Computational Fluid Dynamics (CFD) model was developed using the ANSYS-CFX software to examine the poison injection characteristics in the ACR-1000 design. The effects of calandria tubes on the poison jet growth and poison distribution in the reactor core were discussed.

scholarly journals Multi-Tubular Reactor for Hydrogen Production: CFD Thermal Design and Experimental Testing

Processes ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 31 ◽  
Author(s):  
Elvira Tapia ◽  
Aurelio González-Pardo ◽  
Alfredo Iranzo ◽  
Manuel Romero ◽  
José González-Aguilar ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Experimental Testing ◽  
Tubular Reactor ◽  
Experimental Tests ◽  
Thermal Design ◽  
Thermochemical Cycle ◽  
Cfd Model ◽  
Cfd Modelling ◽  
Solar Reactor ◽  
Computational Fluid Dynamics Cfd

This study presents the Computational Fluid Dynamics (CFD) thermal design and experimental tests results for a multi-tubular solar reactor for hydrogen production based on the ferrite thermochemical cycle in a pilot plant in the Plataforma Solar de Almería (PSA). The methodology followed for the solar reactor design is described, as well as the experimental tests carried out during the testing campaign and characterization of the reactor. The CFD model developed for the thermal design of the solar reactor has been validated against the experimental measurements, with a temperature error ranging from 1% to around 10% depending on the location within the reactor. The thermal balance in the reactor (cavity and tubes) has been also solved by the CFD model, showing a 7.9% thermal efficiency of the reactor. CFD results also show the percentage of reacting media inside the tubes which achieve the required temperature for the endothermic reaction process, with 90% of the ferrite pellets inside the tubes above the required temperature of 900 °C. The multi-tubular solar reactor designed with aid of CFD modelling and simulations has been built and operated successfully.

CFD Modelling of Moisture Content, Air Velocity and Thermal Patterns in the Tombs of Horemeheb in Valley of Kings

2011 ◽  
Author(s):  
Essam E. Khalil
Keyword(s):  
Design System ◽  
Wall Paintings ◽  
Careful Selection ◽  
Cfd Model ◽  
Air Velocity ◽  
Cfd Modelling ◽  
Recirculation Zones ◽  
Computational Fluid Dynamics Cfd ◽  
Thermal Patterns ◽  
Selection Of

Airflow characteristics in ventilated and air-conditioned spaces play an important role to attain comfort and hygiene conditions. This paper utilizes a 3D Computational Fluid Dynamics (CFD) model to assess the airflow and relative humidity characteristics in ventilated and air-conditioned archaeological tomb of Horemheb in the Valley of the Kings in Luxor, Egypt. It is found that the best airside design system can be attained, if the airflow is directed to pass all the enclosure areas before the extraction with careful selection of near wall velocities to avoid any wear or aberration of the tomb-wall paintings. Still all factors and evaluation indices have the shortage to describe the influence of the recirculation zones on the occupancy zone of the visitors and also on the fresh supplied air. The mode of evaluation should assess the airflow characteristics in any tomb passage according to its position in the enclosure and the thermal pattern and air quality.

scholarly journals Using CFD Modelling to Relate Pig Lying Locations to Environmental Variability in Finishing Pens

2020 ◽  
Vol 12 (5) ◽  
pp. 1928 ◽  
Author(s):  
Paul Jackson ◽  
Abozar Nasirahmadi ◽  
Jonathan H. Guy ◽  
Steve Bull ◽  
Peter J. Avery ◽  
...  
Keyword(s):  
Environmental Variability ◽  
Weather Conditions ◽  
Environmental Drivers ◽  
Cfd Model ◽  
Air Velocity ◽  
Cfd Modelling ◽  
Video Cameras ◽  
Finishing Pig ◽  
Computational Fluid Dynamics Cfd ◽  
Sequential Regression

The purpose of this research was to determine which environmental factors within the pen space differ between the locations where pigs choose to lie and areas they avoid. Data on external weather conditions and the construction parameters for an existing commercial finishing pig building were input into a Dynamic Thermal (DT) model generating heat flow and surface temperature patterns in the structure and these were then input into a Computational Fluid Dynamics (CFD) model to generate data on the theoretical spatial patterns of temperature and air velocity within one room of this building on a specified day. The exact location of each pig in six selected pens within this room was taken from images from ceiling-mounted video cameras at four representative time points across the day. Using extracted air velocity and temperature data at the height of 0.64 m above the floor and a grid of approximately 600 mm to create a series of ‘cells’, the effective draught temperature (TED) was calculated from the models for each cell. Using a sequential regression model, the extent to which the actual lying locations of the pigs could be reliably predicted from the environmental conditions generated by model outputs and other pen factors was explored. The results showed that air velocity, TED and proximity to a solid pen partition (all significant at P < 0.05) had significant predictive value and collectively explained 15.55% of the total explained deviation of 17.13%. When the presence of an adjacent pig was considered, results showed that lying next to an adjacent pig, TED, air velocity and temperature accounted for 53.9%, 1.3%, 1.5% and 0.5% of the deviation in lying patterns, respectively (all P < 0.001). Thus, CFD model outputs could potentially provide the industry with a better understanding of which environmental drivers affect pigs’ lying location choice, even before a building is built and stocked.

CFD Modelling With Buoyancy Effects for a Heat and Moisture Transfer Ceiling Panel

2011 ◽  
Author(s):  
Melanie Fauchoux ◽  
Carey Simonson ◽  
David Torvi ◽  
Prabal Talukdar
Keyword(s):  
Flow Field ◽  
Moisture Transfer ◽  
Cfd Model ◽  
Heat And Moisture Transfer ◽  
Cfd Modelling ◽  
Flow Field Characteristics ◽  
Computational Fluid Dynamics Cfd ◽  
The University ◽  
Heat And Moisture ◽  
Insight Into

A heat and moisture transfer panel (HAMP) capable of simultaneously transferring heat and moisture to/from a space to improve indoor air conditions is being developed at the University of Saskatchewan. Experiments have been performed for different air conditions to simulate heating, cooling, humidification and dehumidification of the air by the HAMP. A latent effectiveness value is calculated for each test to show the performance of the HAMP. The HAMP has the highest effectiveness (∼45%) when used to cool the airflow. When used to heat the airflow, the effectiveness is much lower (∼25%). This difference can be attributed to the presence of large buoyancy forces during cooling in comparison to heating. To observe the flow field characteristics under the varying test conditions, a computational fluid dynamics (CFD) model is developed. The CFD model is able to provide a better insight into the features of the flow field. The presented streamlines and isotherms exhibit the effect of buoyancy for various conditions and help in understanding the experimentally determined effectivenesses.

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

Sign in / Sign up

Export Citation Format

Share Document