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 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.

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.

scholarly journals Experimental verification of a CFD model for the closed plant factory under artificial lighting

2020 ◽  
Vol 213 ◽  
pp. 03013
Author(s):  
Wei Lu ◽  
Yiwen Hu ◽  
Shenghan Zhou ◽  
Xin Zhang ◽  
Quan Yuan ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Air Temperature ◽  
Experimental Verification ◽  
Cfd Model ◽  
Air Velocity ◽  
Artificial Lighting ◽  
Mean Relative Error ◽  
Plant Factory ◽  
Computational Fluid Dynamics Cfd ◽  
The Mean

A computational fluid dynamics (CFD) model for the closed plant factory under artificial lighting has been developed in this study, the experimental verification of CFD model with the air velocity value was compared with the measured air temperature value. The results showed that the mean relative error of validation with the air velocity was 15%, and comparable with experimentally observed air temperature profile inside the plant factory with RMSE of 3% which show the utility of CFD to study plant factory microclimatic parameters.

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.

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.

scholarly journals The Effect of Tree-Planting Patterns on the Microclimate within a Courtyard

2019 ◽  
Vol 11 (6) ◽  
pp. 1665 ◽  
Author(s):  
Junying Li ◽  
Jiying Liu ◽  
Jelena Srebric ◽  
Yuanman Hu ◽  
Miao Liu ◽  
...  
Keyword(s):  
Air Temperature ◽  
Local Heat Transfer ◽  
Field Measurements ◽  
Weather Conditions ◽  
Local Heat ◽  
Tree Planting ◽  
Cfd Model ◽  
Planting Pattern ◽  
Wind Velocities ◽  
Computational Fluid Dynamics Cfd

Current landscape design within a courtyard usually does not take into account the influence of the tree-planting pattern, which has an important influence on the outdoor microclimate and occupants’ thermal comfort. At present, the extent of the influence on the microclimate has not yet been made clear. Computational Fluid Dynamics (CFD) was employed to run this model under hot summer weather conditions. Field measurements validated the performance of the CFD model. This study conducted numerical simulations for five different tree-planting patterns, including (i) focused tree-planting (F), (ii) cornered tree-planting (C), (iii) multi-row tree-planting (R), (iv) surround tree-planting (S) and (v) no tree-planting (N). Our study found that the tree-planting pattern affects both the distribution of air temperature and the degree of local heat transfer. Specifically, the C, S and N patterns allow for higher ventilation in the studied courtyard, while the F and R patterns cause lower wind velocities and associated courtyard ventilation. The average air temperature for the C pattern is lower during summer afternoons than the other patterns. The wind flow pattern in the studied courtyard does not vary significantly with different tree-planting patterns. Nevertheless, the general relative humidity in the courtyard does not vary significantly with different tree-planting patterns, except for the N pattern. A future analysis is needed to investigate the mechanisms of the phenomenon.

scholarly journals Development of a CFD Model to Simulate Natural Ventilation in a Semi-Open Free-Stall Barn for Dairy Cows

Buildings ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 183
Author(s):  
Nicoletta Tomasello ◽  
Francesca Valenti ◽  
Giovanni Cascone ◽  
Simona M. C. Porto
Keyword(s):  
Dairy Cows ◽  
Natural Ventilation ◽  
Cooling System ◽  
Simulated Data ◽  
Building Design ◽  
Cfd Model ◽  
Air Velocity ◽  
Cfd Modelling ◽  
Climate Conditions ◽  
Airflow Distribution

Natural ventilation is the most common passive cooling system in livestock buildings. The aim of this research is to assess airflow distribution inside a free-stall barn for dairy cows by computational fluid dynamics (CFD) modelling and simulation. The model is validated by using the average values of experimental data acquired in a free-stall barn, which is considered relevant because it is located in a region characterised by hot climate conditions during the summer that could induce animal heat stress. Simulations are carried out in steady-state conditions, and simulated data are validated by the average values of air velocity measurements. Since the modelled air velocity distribution in the barn fits the real one well, the CFD model is considered reliable to simulate other conditions. The application of the proposed CFD model in the simulation of specific building design alternatives could be aimed at studying the related airflow distribution in order to find the best configuration.

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.

scholarly journals Isothermal Air Flow Investigation in Industrial Baking Oven of Different Impeller Locations using Computational Fluid Dynamics (CFD) Approach

2021 ◽  
Vol 17 (2) ◽  
pp. 73-91
Author(s):  
Olawale Saheed Ismail ◽  
◽  
Adetokunbo Andrew Awonusi ◽  
Rahman Akinoso ◽  
◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Calculation Error ◽  
Back Side ◽  
Air Velocity ◽  
Cfd Modelling ◽  
Back Wall ◽  
Convection Oven ◽  
Flow Investigation ◽  
Computational Fluid Dynamics Cfd

Computational fluid dynamics (CFD) modelling was performed on a forced convection oven to investigate the isothermal airflow. Three oven design configurations based on their impeller location (back, side, and top wall) were compared with respect to their Turbulence Kinetic Energy (TKE) profile to determine the optimal configuration design for quick uniform baking. The air velocity was estimated from both experimental and modelling approaches at specific points in an oven with the back walled impeller. The CFD model was validated resulting in a calculation error of 30.34% of actual velocity which was mainly due to limitation in grid density and the turbulence modelling. The other two oven configurations were simulated and their average TKE data were extracted and compared. The third configuration (impeller at the top wall) was found to have the highest average TKE of 3.55 m2/s2 followed by the first configuration (impeller at the back wall) with 3.30 m2/s2 which provides a relatively uniform TKE distribution across the cavity. The findings show the significance of impeller placement in oven performance.

Sign in / Sign up

Export Citation Format

Share Document