Jessie Bitog | Nueva Vizcaya State University (original) (raw)
Papers by Jessie Bitog
The performance of a fabricated direct-fired corncob furnace was evaluated to determine best comb... more The performance of a fabricated direct-fired corncob furnace was evaluated to determine best combinations of operating parameters involving fuel feed rate, combustion air, and fuel size. The furnace had the following components: hopper; rotary feeder; variable motor; inclined grate; and horizontal grate. The furnace wall was made up of cement and red volcanic cinder. Result showed no trend from the computed burning efficiency when the fuel feed rate was varied. All the levels of combustion air and fuel size significantly affect the burning efficiency of the furnace. All levels of the independent parameters revealed significant differences in the furnace efficiency. In terms of furnace capacity, all independent parameters revealed no significant differences. Theoretically, the furnace can supply the required energy needed for the two-ton flat bed dryer to dry corn grains from 28% to 12% moisture content for 8 hours of operation. Fuel feed rate of 15 kg/hr with 3300 cubic meter per ho...
International Symposium on High Technology for Greenhouse Systems: GreenSys2009, 2011
Development of new-source of energy which is renewable and carbon neutral is necessary for mankin... more Development of new-source of energy which is renewable and carbon neutral is necessary for mankind's environmental and economic sustainability. Among the new sources of energy being explored, biodiesel derived from oil crops and from microalgae is the most potential and promising source. However, the production period of oil plants is also one of the primary concerns. More so, meeting the increasing demand of energy from oil plants would require the world to use virtually all of its arable land which also competes with the increasing demand of food supply. Microalgae which is the most potential source of biodiesel overcomes such drawbacks. Microalgae use primary sunlight and CO 2 to produce oil. Oil content in microalgae can exceed 80% by weight of dry mass and they can double their biomass within 24 h. Although a number of photobioreactors (PBRs) have been proposed for large scale production of microalgae, only a few can be practically used because of the following factors: most designed PBRs limit the entry of light throughout the PBR, the mixing technique to attain a homogenous mixture throughout the PBR of is not yet achieved, the injection mechanism of CO 2 and other nutrients needed for optimum growth of microalgae is not yet perfected. Computational Fluid Dynamics (CFD) which has a wide application in the field of engineering will be used to solve the problems presented. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. More so, an optimum design of a PBR to maximize its production efficiency can be achieved using the pre-processing and the main module approach of CFD.
Ist International Symposium on CFD Applications in Agriculture, 2013
ABSTRACT Windbreaks systems play an active role in improving the quality of the natural environme... more ABSTRACT Windbreaks systems play an active role in improving the quality of the natural environment, accelerating the development of agriculture, forestry and animal husbandry, and increasing ecological, social and economical benefits. In a vast reclaimed land, where detrimental dusts are of enormous concern, windbreak's main purpose can be exclusively to control soil erosion, dust generation and diffusion. Artificial and natural windbreaks are very effective in minimizing the wind velocity especially in the dusts source areas, where it is the main catalyst of soil erosion, dust generation and diffusion. In this study, numerical simulation was utilized to evaluate the performance of both artificial and natural windbreaks in minimizing wind velocity. Windbreak fences of varied height and porosity and arranged in an array with different gap distance were investigated. For natural windbreaks, the effectiveness of trees in reducing the wind velocity was measured and quantified. Field experiments as well as wind tunnel studies were initially conducted to establish the validity of the simulation models. Simulation results were evaluated and suitable windbreak design for artificial and natural windbreaks were recommended. The numerical technique utilized in this study has proven its effectiveness in investigating dusts generation and diffusion which saves significant amount of time, labor and cost. INTRODUCTION Amidst the limited land resources of the country, Korea has been reclaiming lands for agricultural and industrial purposes. By 2006, 38% or approximately 1550 km 2 of coastal wetlands had been reclaimed, including a 400 km 2 area known as Saemanguem from three cities namely Gunsan, Buan and Kimje in the province of Chunla-book, South Korea (Korea Statistical Information Service, 2006). However, the generation of dust from the ground surface and its diffusion to nearby surrounding areas has become an emerging concern. This usually happens during the very dry months from late February to May where the wind velocity reaches from 2.0 to 7.0 m/s (Bitog et al., 2009). The dusts also contains significant amount of sodium chloride (NaCl) which is very harmful to plants. To minimize these problems, constructing artificial windbreaks within the dusts source areas to significantly reduce the wind velocity are the best options. Artificial
Odor is one of the major nuisances in the environment. In most countries, odor annoyance from liv... more Odor is one of the major nuisances in the environment. In most countries, odor annoyance from livestock production is an increasing problem in community. In order to reduce the odor inconvenience and establish a good relation between livestock industries and the surrounding communities, many studies, such as diffusion simulations and field experiments, on the odor dispersion and its reduction have been investigated. These studies need to accompany the aerodynamic approach, as a main mechanism of diffusion phenomenon, and computational fluid dynamics(CFD) can be effectively used to study this kind of research. CFD considers both various wind conditions as well as topographical conditions to study aerodynamic phenomenon. Therefore the ultimate objective of the study was to develop an aerodynamic model to predict qualitatively and quantitatively odor diffusion from livestock. In this study, as the first step of this study, various phenomena and factors of odor diffusion from livestock ...
This paper discusses the quantitative effect of windbreaks on wind velocity in the reclaimed land... more This paper discusses the quantitative effect of windbreaks on wind velocity in the reclaimed land at Saemangeum in South Korea. The effectiveness of windbreaks to reduce the velocity to prevent the generation and diffusion of dust are very critical. Using CFD simulations, the effects of porosity, height, and distance between the adjacent fences as well as the effect of tree windbreaks were investigated. A wind tunnel test was conducted and data gathered were used to develop and validate the CFD models. From the experiments and CFD simulations, the overall percentage difference of the measured velocities was 7.20% which is acceptable to validate the CFD models. In the case of tree windbreak simulation, the methodologies to model the real effect of tree windbreak were conducted and compared such as the application of tree porosity, inertial resistance and input velocity. Results have shown that a windbreak fence with porosity of 0.2 and a height of 0.6 m and constructed in array at 6 ...
In South Korea, as the living standard has been getting higher, meat consumption is steadily incr... more In South Korea, as the living standard has been getting higher, meat consumption is steadily increasing. To meet the country's demand, livestock houses become larger and wider with increased raising density. In larger livestock houses, pollutants such as flake of pig skin, excrement, odor, various dusts and noxious gas like ammonia are excessively accumulated inside the facility. These will cause weak immunity for the pigs, diminution of productivity and degeneration of working condition. These problems can be solved through the ventilation performance of the facility. In the winter time, ventilation must be controlled to minimum to maintain a suitable thermal condition. However, this affects the other internal environmental condition because of the minimum ventilation. The installation of "wet air cleaner" especially in the winter time can be an alternative solution. For efficient application of this machine, there is a need to understand the existing ventilation cond...
Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for ... more Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for its growth, such as light, nutrients, CO2, heat, etc. is now getting more popular in the last decade. Among the many types of PBRs, the bubble column type is very attractive because of its simple construction and easy operation. However, despite the availability of these PBRs, only a few of them can be practically used for mass production. Many limitations still holdback their use especially during their scale-up. To enlarge the culture volume and productivity while supplying optimum environmental conditions, various PBR structures and process control are needed to be investigated. In this study, computational fluid dynamics (CFD) was economically used to design a bubble-column type PBR taking the place of field experiments. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. To study bubble column PBR with CFD, the most important factor is...
In livestock industry, damage caused by the epidemic diseases such as Foot-and-Mouth Disease (FMD... more In livestock industry, damage caused by the epidemic diseases such as Foot-and-Mouth Disease (FMD), Highly-Pathogenic-Avian-Influenza (HPAI) and Porcine-Reproductive-and-Respiratory-Syndrome (PRRS) was very serious. The financial loss incurred from FMD alone which occurred on Nov. 2011 in Korea was estimated at 3 billion won, 23 % of annual livestock industry production. The livestock industry in Korea has greater risk of disease infection because of high density production, etc. Investigating the spread of livestock diseases should consider both direct and indirect contact as well as other various factors including airborne. Airborne infection of livestock disease was first hypothesised in the early 1900s, however, field experimental studies are still limited. Furthermore, no protocol is available in detecting airborne viruses in the field. In this study, effective virus samplers were investigated by comparative analysis of the type of samplers used detect to airborne virus. Labora...
Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating... more Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating facilities are very important preceding factors to save energy as well as initial and maintenance costs of operating a greenhouse. Recently, building energy simulation (BES) technique to simulate a model similar to the actual conditions through a variety of dynamic simulation methods, and predict and analyze the flow of energy is being actively introduced and developed. As a fundamental research to apply the BES technique which is mainly used for analysis of general buildings, to greenhouse, this research designed four types of naturally-ventilated greenhouses using one of commercial programs, TRNSYS, and then compared and analyzed their energy load properties, by applying meteorological data collected from six regions in Korea. When comparing the greenhouse load of each region depending on latitude and topographical characteristics through simulation, Chuncheon had nearly 9~49 % higher...
Journal of The Korean Society of Agricultural Engineers, 2008
Transactions of the ASABE, 2008
... The authors are Se-Woon Hong, Graduate Student, In-Bok Lee, ASABE Member Engineer, Assistant ... more ... The authors are Se-Woon Hong, Graduate Student, In-Bok Lee, ASABE Member Engineer, Assistant Professor, Hyun-Seop Hwang, Junior ... and Life Sciences, College of Agricultural and Life Sciences, Seoul National University, Seoul, Korea; Kee-Sung Kim, Research Professor ...
Journal of The Korean Society of Agricultural Engineers, 2012
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT Fugitive dust dispersion was studies in Saemangeum reclaimed land which developed 40,100... more ABSTRACT Fugitive dust dispersion was studies in Saemangeum reclaimed land which developed 40,100 ha and located at the west coastal part of Korea. The salty dusts can affect to nearby farms. A computational fluid dynamics (CFD) model was developed to predict the dispersion of fugitive dust considering the topography of the area. Results showed that the dust concentrations are highly connected with the changes of dust source area. The dust concentration has been decreased from 2006 to 2010, and it is expected to decrease further as more dust source areas are being covered by plants. Dust dispersion ranges of CFD result were compared with that of field experiment at the same measuring points for the CFD validity, and the results at stable weather condition were very acceptable with a 6.8% error. On the basis of 10 µm particle size, the dispersion distance of fugitive dust resulted in about 2,500m with the wind velocity of 5.0m/s.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT HPAI (Highly pathogenic avian influenza) which is a legally designated epidemic disease ... more ABSTRACT HPAI (Highly pathogenic avian influenza) which is a legally designated epidemic disease generally shows rapid spread resulting in high mortality rate as well as severe economic damages. Because Korea is neighbor with China and south-east Asia where HPAI have occurred frequently, there is a high possibility for HPAI outbreak. A prompt treatment against epidemics is most important for minimize of disease spread. The spread of HPAI should be considered by both direct and indirect contact as well as various spread factors including airborne spread. There is high risk of rapid propagation of HPAI via air because most of farms in Korea are collective. Field experiments for the mechanism of disease spread have limitations such as unstable weather condition and difficulties in maintaining experimental conditions. In this study computational fluid dynamics which has been actively used for mass transfer modeling were adapted. Korea has complex terrains and many livestock farms are located in the mountain regions. GIS was also used to estimate spreads of virus attached aerosol by means of designing three dimensional complicated geometry including farm location, road network, and related facilities. This can be used as back data in order to take preventive measures against HPAI occurrence and spread.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
... However, the advance of computational fluid dynamics (CFD) and its continuous development has... more ... However, the advance of computational fluid dynamics (CFD) and its continuous development has paved ... VOF model could visualize the bubbles because the air and culture medium were ... Light intensity, carbon dioxide, temperature and nutrients are the major parameters for ...
Livestock Environment VIII, 31 August - 4 September 2008, Iguassu Falls, Brazil, 2008
... Dust, ammonia, internal airflow, ventilation rate and surface temperature were measured using... more ... Dust, ammonia, internal airflow, ventilation rate and surface temperature were measured using the ... in hot season with high temperature, this ventilation condition can cause high stress for pigs. The experimental pig house posed problems in terms of the internal rearing condition ...
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT In Korea, the heating cost for the Horticulture industry is considering as a big problem... more ABSTRACT In Korea, the heating cost for the Horticulture industry is considering as a big problem where it occupies about 58% from total costs. Almost 80% from the heating systems are using fossil fuel where it cause economic crisis. Since industrialization, environment pollution, global warming and lack of natural resource were occurred because of increased rapidly using of fossil fuel. Among the renewable energy, ground heat pump system is suitable to control internal environmental conditions in greenhouse where it has a steady temperature. Generally conventional greenhouses are using the oil heating system during the cold season. Accordingly, the geothermal heating system is used for reducing costs of heating, management and operation. But the initial investments of the geothermal heating system are very high in comparison to conventional heating system because of its equipment costs. Consequently, according to exact calculations of heating load, greenhouse geothermal heating systems must be designed efficiently.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
In agricultural-buildings like livestock houses and greenhouses, environmental conditions are con... more In agricultural-buildings like livestock houses and greenhouses, environmental conditions are controlled by ventilation-systems. Comprehension of ventilation is important to improve the internal growth conditions. Notable researchers in the field of architectural-science have been using "Age-of-air" theory to investigate ventilation-efficiencies. However, this has not yet been applied in agricultural fields. The concepts of LMA and LMR were used to evaluate the-distribution of fresh air and the potential for eliminating-contaminants. However, experiments had been limited due to a shortage of experimental-devices and unstable tracer-gas. In this study, the Age-of-air concept and CFD were employed to address the mentioned limitations. A 3-dimensional chamber was designed to accurately implement and verify the Age-of-air concept via simulation analysis. The simulation results were compared with the results of the experiment which was conducted via the tracer-gas approach. In validating the computations of the LMAs and LMRs, the results showed similar tendencies of distribution and average errors of 9 and 13%, respectively. It was concluded that the simulation for implementation of the Age-of-air was designed reasonably. The results showed that when the ventilation rate increased, the Age-of-air values decreased; however, when comparing air exchange efficiencies, the values had an opposite tendency. Based on the results, the research could be upgraded to quantitatively determine the overall or local ventilation-efficiencies in agricultural-facilities using the Age-of-air theory
The performance of a fabricated direct-fired corncob furnace was evaluated to determine best comb... more The performance of a fabricated direct-fired corncob furnace was evaluated to determine best combinations of operating parameters involving fuel feed rate, combustion air, and fuel size. The furnace had the following components: hopper; rotary feeder; variable motor; inclined grate; and horizontal grate. The furnace wall was made up of cement and red volcanic cinder. Result showed no trend from the computed burning efficiency when the fuel feed rate was varied. All the levels of combustion air and fuel size significantly affect the burning efficiency of the furnace. All levels of the independent parameters revealed significant differences in the furnace efficiency. In terms of furnace capacity, all independent parameters revealed no significant differences. Theoretically, the furnace can supply the required energy needed for the two-ton flat bed dryer to dry corn grains from 28% to 12% moisture content for 8 hours of operation. Fuel feed rate of 15 kg/hr with 3300 cubic meter per ho...
International Symposium on High Technology for Greenhouse Systems: GreenSys2009, 2011
Development of new-source of energy which is renewable and carbon neutral is necessary for mankin... more Development of new-source of energy which is renewable and carbon neutral is necessary for mankind's environmental and economic sustainability. Among the new sources of energy being explored, biodiesel derived from oil crops and from microalgae is the most potential and promising source. However, the production period of oil plants is also one of the primary concerns. More so, meeting the increasing demand of energy from oil plants would require the world to use virtually all of its arable land which also competes with the increasing demand of food supply. Microalgae which is the most potential source of biodiesel overcomes such drawbacks. Microalgae use primary sunlight and CO 2 to produce oil. Oil content in microalgae can exceed 80% by weight of dry mass and they can double their biomass within 24 h. Although a number of photobioreactors (PBRs) have been proposed for large scale production of microalgae, only a few can be practically used because of the following factors: most designed PBRs limit the entry of light throughout the PBR, the mixing technique to attain a homogenous mixture throughout the PBR of is not yet achieved, the injection mechanism of CO 2 and other nutrients needed for optimum growth of microalgae is not yet perfected. Computational Fluid Dynamics (CFD) which has a wide application in the field of engineering will be used to solve the problems presented. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. More so, an optimum design of a PBR to maximize its production efficiency can be achieved using the pre-processing and the main module approach of CFD.
Ist International Symposium on CFD Applications in Agriculture, 2013
ABSTRACT Windbreaks systems play an active role in improving the quality of the natural environme... more ABSTRACT Windbreaks systems play an active role in improving the quality of the natural environment, accelerating the development of agriculture, forestry and animal husbandry, and increasing ecological, social and economical benefits. In a vast reclaimed land, where detrimental dusts are of enormous concern, windbreak's main purpose can be exclusively to control soil erosion, dust generation and diffusion. Artificial and natural windbreaks are very effective in minimizing the wind velocity especially in the dusts source areas, where it is the main catalyst of soil erosion, dust generation and diffusion. In this study, numerical simulation was utilized to evaluate the performance of both artificial and natural windbreaks in minimizing wind velocity. Windbreak fences of varied height and porosity and arranged in an array with different gap distance were investigated. For natural windbreaks, the effectiveness of trees in reducing the wind velocity was measured and quantified. Field experiments as well as wind tunnel studies were initially conducted to establish the validity of the simulation models. Simulation results were evaluated and suitable windbreak design for artificial and natural windbreaks were recommended. The numerical technique utilized in this study has proven its effectiveness in investigating dusts generation and diffusion which saves significant amount of time, labor and cost. INTRODUCTION Amidst the limited land resources of the country, Korea has been reclaiming lands for agricultural and industrial purposes. By 2006, 38% or approximately 1550 km 2 of coastal wetlands had been reclaimed, including a 400 km 2 area known as Saemanguem from three cities namely Gunsan, Buan and Kimje in the province of Chunla-book, South Korea (Korea Statistical Information Service, 2006). However, the generation of dust from the ground surface and its diffusion to nearby surrounding areas has become an emerging concern. This usually happens during the very dry months from late February to May where the wind velocity reaches from 2.0 to 7.0 m/s (Bitog et al., 2009). The dusts also contains significant amount of sodium chloride (NaCl) which is very harmful to plants. To minimize these problems, constructing artificial windbreaks within the dusts source areas to significantly reduce the wind velocity are the best options. Artificial
Odor is one of the major nuisances in the environment. In most countries, odor annoyance from liv... more Odor is one of the major nuisances in the environment. In most countries, odor annoyance from livestock production is an increasing problem in community. In order to reduce the odor inconvenience and establish a good relation between livestock industries and the surrounding communities, many studies, such as diffusion simulations and field experiments, on the odor dispersion and its reduction have been investigated. These studies need to accompany the aerodynamic approach, as a main mechanism of diffusion phenomenon, and computational fluid dynamics(CFD) can be effectively used to study this kind of research. CFD considers both various wind conditions as well as topographical conditions to study aerodynamic phenomenon. Therefore the ultimate objective of the study was to develop an aerodynamic model to predict qualitatively and quantitatively odor diffusion from livestock. In this study, as the first step of this study, various phenomena and factors of odor diffusion from livestock ...
This paper discusses the quantitative effect of windbreaks on wind velocity in the reclaimed land... more This paper discusses the quantitative effect of windbreaks on wind velocity in the reclaimed land at Saemangeum in South Korea. The effectiveness of windbreaks to reduce the velocity to prevent the generation and diffusion of dust are very critical. Using CFD simulations, the effects of porosity, height, and distance between the adjacent fences as well as the effect of tree windbreaks were investigated. A wind tunnel test was conducted and data gathered were used to develop and validate the CFD models. From the experiments and CFD simulations, the overall percentage difference of the measured velocities was 7.20% which is acceptable to validate the CFD models. In the case of tree windbreak simulation, the methodologies to model the real effect of tree windbreak were conducted and compared such as the application of tree porosity, inertial resistance and input velocity. Results have shown that a windbreak fence with porosity of 0.2 and a height of 0.6 m and constructed in array at 6 ...
In South Korea, as the living standard has been getting higher, meat consumption is steadily incr... more In South Korea, as the living standard has been getting higher, meat consumption is steadily increasing. To meet the country's demand, livestock houses become larger and wider with increased raising density. In larger livestock houses, pollutants such as flake of pig skin, excrement, odor, various dusts and noxious gas like ammonia are excessively accumulated inside the facility. These will cause weak immunity for the pigs, diminution of productivity and degeneration of working condition. These problems can be solved through the ventilation performance of the facility. In the winter time, ventilation must be controlled to minimum to maintain a suitable thermal condition. However, this affects the other internal environmental condition because of the minimum ventilation. The installation of "wet air cleaner" especially in the winter time can be an alternative solution. For efficient application of this machine, there is a need to understand the existing ventilation cond...
Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for ... more Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for its growth, such as light, nutrients, CO2, heat, etc. is now getting more popular in the last decade. Among the many types of PBRs, the bubble column type is very attractive because of its simple construction and easy operation. However, despite the availability of these PBRs, only a few of them can be practically used for mass production. Many limitations still holdback their use especially during their scale-up. To enlarge the culture volume and productivity while supplying optimum environmental conditions, various PBR structures and process control are needed to be investigated. In this study, computational fluid dynamics (CFD) was economically used to design a bubble-column type PBR taking the place of field experiments. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. To study bubble column PBR with CFD, the most important factor is...
In livestock industry, damage caused by the epidemic diseases such as Foot-and-Mouth Disease (FMD... more In livestock industry, damage caused by the epidemic diseases such as Foot-and-Mouth Disease (FMD), Highly-Pathogenic-Avian-Influenza (HPAI) and Porcine-Reproductive-and-Respiratory-Syndrome (PRRS) was very serious. The financial loss incurred from FMD alone which occurred on Nov. 2011 in Korea was estimated at 3 billion won, 23 % of annual livestock industry production. The livestock industry in Korea has greater risk of disease infection because of high density production, etc. Investigating the spread of livestock diseases should consider both direct and indirect contact as well as other various factors including airborne. Airborne infection of livestock disease was first hypothesised in the early 1900s, however, field experimental studies are still limited. Furthermore, no protocol is available in detecting airborne viruses in the field. In this study, effective virus samplers were investigated by comparative analysis of the type of samplers used detect to airborne virus. Labora...
Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating... more Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating facilities are very important preceding factors to save energy as well as initial and maintenance costs of operating a greenhouse. Recently, building energy simulation (BES) technique to simulate a model similar to the actual conditions through a variety of dynamic simulation methods, and predict and analyze the flow of energy is being actively introduced and developed. As a fundamental research to apply the BES technique which is mainly used for analysis of general buildings, to greenhouse, this research designed four types of naturally-ventilated greenhouses using one of commercial programs, TRNSYS, and then compared and analyzed their energy load properties, by applying meteorological data collected from six regions in Korea. When comparing the greenhouse load of each region depending on latitude and topographical characteristics through simulation, Chuncheon had nearly 9~49 % higher...
Journal of The Korean Society of Agricultural Engineers, 2008
Transactions of the ASABE, 2008
... The authors are Se-Woon Hong, Graduate Student, In-Bok Lee, ASABE Member Engineer, Assistant ... more ... The authors are Se-Woon Hong, Graduate Student, In-Bok Lee, ASABE Member Engineer, Assistant Professor, Hyun-Seop Hwang, Junior ... and Life Sciences, College of Agricultural and Life Sciences, Seoul National University, Seoul, Korea; Kee-Sung Kim, Research Professor ...
Journal of The Korean Society of Agricultural Engineers, 2012
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT Fugitive dust dispersion was studies in Saemangeum reclaimed land which developed 40,100... more ABSTRACT Fugitive dust dispersion was studies in Saemangeum reclaimed land which developed 40,100 ha and located at the west coastal part of Korea. The salty dusts can affect to nearby farms. A computational fluid dynamics (CFD) model was developed to predict the dispersion of fugitive dust considering the topography of the area. Results showed that the dust concentrations are highly connected with the changes of dust source area. The dust concentration has been decreased from 2006 to 2010, and it is expected to decrease further as more dust source areas are being covered by plants. Dust dispersion ranges of CFD result were compared with that of field experiment at the same measuring points for the CFD validity, and the results at stable weather condition were very acceptable with a 6.8% error. On the basis of 10 µm particle size, the dispersion distance of fugitive dust resulted in about 2,500m with the wind velocity of 5.0m/s.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT HPAI (Highly pathogenic avian influenza) which is a legally designated epidemic disease ... more ABSTRACT HPAI (Highly pathogenic avian influenza) which is a legally designated epidemic disease generally shows rapid spread resulting in high mortality rate as well as severe economic damages. Because Korea is neighbor with China and south-east Asia where HPAI have occurred frequently, there is a high possibility for HPAI outbreak. A prompt treatment against epidemics is most important for minimize of disease spread. The spread of HPAI should be considered by both direct and indirect contact as well as various spread factors including airborne spread. There is high risk of rapid propagation of HPAI via air because most of farms in Korea are collective. Field experiments for the mechanism of disease spread have limitations such as unstable weather condition and difficulties in maintaining experimental conditions. In this study computational fluid dynamics which has been actively used for mass transfer modeling were adapted. Korea has complex terrains and many livestock farms are located in the mountain regions. GIS was also used to estimate spreads of virus attached aerosol by means of designing three dimensional complicated geometry including farm location, road network, and related facilities. This can be used as back data in order to take preventive measures against HPAI occurrence and spread.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
... However, the advance of computational fluid dynamics (CFD) and its continuous development has... more ... However, the advance of computational fluid dynamics (CFD) and its continuous development has paved ... VOF model could visualize the bubbles because the air and culture medium were ... Light intensity, carbon dioxide, temperature and nutrients are the major parameters for ...
Livestock Environment VIII, 31 August - 4 September 2008, Iguassu Falls, Brazil, 2008
... Dust, ammonia, internal airflow, ventilation rate and surface temperature were measured using... more ... Dust, ammonia, internal airflow, ventilation rate and surface temperature were measured using the ... in hot season with high temperature, this ventilation condition can cause high stress for pigs. The experimental pig house posed problems in terms of the internal rearing condition ...
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
ABSTRACT In Korea, the heating cost for the Horticulture industry is considering as a big problem... more ABSTRACT In Korea, the heating cost for the Horticulture industry is considering as a big problem where it occupies about 58% from total costs. Almost 80% from the heating systems are using fossil fuel where it cause economic crisis. Since industrialization, environment pollution, global warming and lack of natural resource were occurred because of increased rapidly using of fossil fuel. Among the renewable energy, ground heat pump system is suitable to control internal environmental conditions in greenhouse where it has a steady temperature. Generally conventional greenhouses are using the oil heating system during the cold season. Accordingly, the geothermal heating system is used for reducing costs of heating, management and operation. But the initial investments of the geothermal heating system are very high in comparison to conventional heating system because of its equipment costs. Consequently, according to exact calculations of heating load, greenhouse geothermal heating systems must be designed efficiently.
2011 Louisville, Kentucky, August 7 - August 10, 2011, 2011
In agricultural-buildings like livestock houses and greenhouses, environmental conditions are con... more In agricultural-buildings like livestock houses and greenhouses, environmental conditions are controlled by ventilation-systems. Comprehension of ventilation is important to improve the internal growth conditions. Notable researchers in the field of architectural-science have been using "Age-of-air" theory to investigate ventilation-efficiencies. However, this has not yet been applied in agricultural fields. The concepts of LMA and LMR were used to evaluate the-distribution of fresh air and the potential for eliminating-contaminants. However, experiments had been limited due to a shortage of experimental-devices and unstable tracer-gas. In this study, the Age-of-air concept and CFD were employed to address the mentioned limitations. A 3-dimensional chamber was designed to accurately implement and verify the Age-of-air concept via simulation analysis. The simulation results were compared with the results of the experiment which was conducted via the tracer-gas approach. In validating the computations of the LMAs and LMRs, the results showed similar tendencies of distribution and average errors of 9 and 13%, respectively. It was concluded that the simulation for implementation of the Age-of-air was designed reasonably. The results showed that when the ventilation rate increased, the Age-of-air values decreased; however, when comparing air exchange efficiencies, the values had an opposite tendency. Based on the results, the research could be upgraded to quantitatively determine the overall or local ventilation-efficiencies in agricultural-facilities using the Age-of-air theory