Kyeong-Seok Kwon

Monitoring of the Fugitive and Suspended Dust Dispersion at the Reclaimed Land and Neighboring Farms: Monitoring in Gim-je

A study on fugitive dust dispersion was conducted at Saemanguem reclaimed area located at the west coastal area of Jeon-buk Province Total reclaimed area is 40,100ha developed by building a 33km long sea dike through Gunsan, Gimje, and Buan. (Land: 28,300ha, Fresh Water Lake: 11,800ha) After this area was completely reclaimed in 2006, there has been high possibility of dust generation and dispersion to the neighboring area. The dust generated at the reclaimed land was composed mainly of minerals with high salinity, and it could make harmful effect on crop production as well on to human`s health such as eye irritation and respiratory disease. Especially, when those aerosol particles are reached on the leaves of farm crops, the photosynthesis and respiration of the plants can be under restraint resulting in the decrease of agricultural productivity of the nearby farm areas. Furthermore, highly concentrated salty particles can directly damage the leaf cells. In this study, field experiment has been conducted to regularly measure the locally suspended dust particles and analyze how they were dispersed to the neighboring areas. The collected dust particles were analyzed to examine theirs sizes, concentrations, and components. The SPSS statistical program was also used to separate the dust concentration generated by the reclaimed land from the total dust concentration measured at the measuring locations.

Evaluation and CFD Modelling of Flow behind Livestock Ventilation Fan for Small-Scale Wind Power Generation

The objectives of this paper were to evaluate the wind flow behind the livestock ventilation fan for small-scale wind power generation and to make flow profiles of imaginary ventilation fan for future simulation works. The field experiments using typical 50-inch fan indicated that the wind flow behind the ventilation fan had a good possibility of power generation with its high and steady wind speeds up to a distance of 2 m. The expected electricity yield was almost 101~369 W with a small (0.8 m radius) wind turbine. The decline of ventilation fan performance caused by the obstacle was also not significant with about 4 % from a distance of 2 m. The flow profiles for the computational fluid dynamics (CFD) simulation was created by combining the direction vectors analyzed from tuft visualization test and the flow predicted by the rotating fan modeling. The flow profiles are expected to provide an efficient saving of computational time and cost to design a better wind turbine system in future works.

Prediction of Greenhouse Energy Loads using Building Energy Simulation (BES)

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 heating load per year than other regions, but its annual cooling load was the reverse to it. Except for Jeju, 1-2W type greenhouses in five regions showed about 17 % higher heating load than a widespan type greenhouse, and 1-2W type greenhouses in Chuncheon, Suwon, Cheongju, Daegu, Cheonju and Jeju had 23 %, 20 %, 17 %, 16 %, 18 % and 20 % higher cooling load respectively than a wide span-type one. Glasshouse and vinyl greenhouse showed 8~11 % and 10~12 % differences respectively in heating load, while 2~10 % and 7~10 % differences in cooling load respectively.

Analysis of Jet-drop Distance from the Multi Opening Slots of Forced-ventilation Broiler House

In the winter season, when the ventilation system is operating, the fresh cold air from the slot-type openings of broiler house which directly reached the animal zone can cause various problems such as thermal stress, decreasing of feed and water consumption, occurrence of respiratory disease, and etc. Therefore it is very important to control the trajectory of aero-flow from the slot openings to induce an efficient thermal heat change. Jet-drop distance model was proposed to predict and control the jet-trajectory. However their study was restricted due to the small scaled model and difficulties of measuring the Jet-drop distance. In this study, CFD was applied to analyze qualitatively and quantitatively the jet-drop distance in a real broiler house. The various variables were considered such as installed slot-angle, designed ventilation rate, and the outdoor ambient temperature. From the present study, two linear-regression models using the Jet-drop factor and corrected Archimedes number, and their R-squared values 0.744 and 0.736, respectively, were used. From this study, the applicability of CFD on the analysis of Jet-drop distance model was confirmed.

Analysis on the Optimum Location of an Wet Air Cleaner in a Livestock House using CFD technology

ABSTRACT In South Korea, as the living standard has been getting higher, meat consumption is steadily increasing. To meet the countrys 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 condition and analyze the interaction of existing ventilation system with the wet air cleaner considering its appropriate location. In this study, the existing ventilation system as well as the internal environmental condition negatively inside the facility with the wet air cleaner has been studied using CFD technology. The CFD simulation model was validated from the study conducted by Seo et al. (2008). Results show that the elimination rate of ammonia was 39.4 % and stability could be improved to 35.1 % (Comparing case 5 to 1 where wet air cleaner machine was not used). It can therefore be concluded that case 5 shows the optimum location of a wet air cleaner in the livestock house.

LOCAL MEAN AGES OF AIR IN A ROOM WITH MULTIPLE INLETS

This paper considers the age of air in a ventilated space with multiple supply inlets; the local mean age (LMA) of air is different from one inlet to another in multiple supply inlet situations. The purpose of this paper is to investigate theoretically the relations between the LMAs arising from each supply inlet and the overall combined LMA for all inlets. Transient concentration distributions are calculated using a CFD package in a simple room configuration with two inlets and one outlet, to verify the relations. Tracer gases are injected with a step-up method at each supply inlet individually, and at both inlets simultaneously. As a result, it can be found that the steady state concentration, with a continuous tracer injection at each supply inlet, works as a weighting factor for the corresponding LMA in calculating the overall combined LMA for the multiple inlet situations.

Analysis of Research Trend and Core TechnologiesBased on ICT to Materialize Smart-farm

Korean government has planned to increase the productivity of horticultural crops and to expand supply smart greenhouse for energy saving by modernization of horticultural facilities based on ICT in policy. However, the diversity and linkages of monitoring and control are significantly insufficient in the agricultural sector in the current situation. Therefore, development of a service system with smart-farm based on the internet of things(IoT) for intelligent systemization of all the process of agricultural production through remote control using complex algorithm for diverse monitoring and control is required. In this study, domestic and international research trend related to ICTbased horticultural facilities was briefly introduced and limits were analyzed in the domestic application of the advanced technology. Finally, future core technologies feasible to graft in agricultural field were reviewed. Additional key words : converging technology, greenhouse, monitoring, remote control, service platform

Development of Straightforward Method of Estimating LMA and LMR using Computational Fluid Dynamics Technology

Ventilation efficiency has an important role in agricultural facilities such as greenhouse and livestock house to keep internally optimum environmental condition. Age-of-air concept allows to assess the ventilation efficiency of an agricultural facility according to estimating the ability of fresh air supply and contaminants emission using LMA and LMR. Most of these methods use a tracer gas method which has some limitations in experiment like dealing unstable and invisible gas. Therefore, the aim of this study was to develop a straightforward method to calculate age-of-air values with CFD simulation which has the advantage of saving computational time and resources and these method can solve the limitations in experiment using tracer gas method. The main idea of LMA computation is to solve the passive scalar transport equation with the assumption that the production of the time scalar throughout the room is uniform. In case of LMR calculation, the transport of the time scalar was reversed compulsively using UDF. The methodology to validate the results of this study was established by comparing with preceding research that had performed a computing LMA and LMR value by laboratory experiments and CFD simulations using tracer gas. As a result, the error was presented similarly level of results of preceding research. Some big errors could be caused by stagnated area and incongruity turbulence model. while the computational time was reduced to almost one fourth of that by preceding research.

Measurement and Analysis of Dust Concentration in a Fattening Pig House Considering Respiratory Welfare of Pig Farmers

In swine house, dust generation comes from various sources and is known to be harmful both for the animals and the farmers because the dust contains biological and gaseous matters. When farmers are constantly exposed to the dusts, they can suffer chronic or acute respiratory symptoms and have high probability of manifesting various diseases. To address this problem, understanding of the mechanism of dust generation is very important. In this paper, the dust concentration of inhalable, respirable, TSP and were monitored and analyzed according to the pig-activity level, ventilation quantity and feeding method in fattening pig house. From the measured results, in case of the concentration of TSP, an inverse-linear relation with ventilation rate (

Analysis of the Disease Spread in a Livestock Building Using Tracer Gas Experiment

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