• Title/Summary/Keyword: FVM

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Effects of Dietary Flammulina velutipes Mycelium on Broiler Chick Performance, Pathogenic Bacterial Counts in Caecal Contents and Amount of NH3 in Excreta (팽이버섯 균사체의 급여가 육계의 생산성, 맹장 내 병원성 미생물 및 배설물 중의 NH3 발생량에 미치는 영향)

  • Lee, Sang-Bum;Choi, Young-Ha;Cho, Seong-Keun;Shin, Teak-Soon;Cho, Byung-Wook;Kang, Han-Seok;Kim, Keun-Ki;Kim, Seon-Ku;Lee, Hong-Gu
    • Journal of Animal Science and Technology
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    • v.54 no.5
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    • pp.341-347
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    • 2012
  • The purpose of this study was to evaluate the effects of dietary Flammulina velutipes mycelium (FVM) on broiler chick performance, pathogenic bacterial (E. coli, Salmonella) counts in caecal contents and amount of $NH_3$ in excreta. Ninety-six broiler chicks (HanHyup No. 3, Korea) were divided into four groups: 1) Control (basal diet), 2) T1 (supplemented with 1% FVM), 3) T2 (3% FVM), and T3 (5% FVM), and rose for 7 weeks. In results, there were no significant differences among treatments in weight gain, feed intake, feed efficiency and carcass yield. However, giblets were significantly increased in FVM treatments compared with control group (p<0.05). The number of Salmonella in caecum was significantly decreased in FVM treatments compared with control group (p<0.05). The number of E. coli was decreased in T2 but increased in T1 and T3 compared with control group. The emission of fecal $NH_3$ gas was significantly decreased in accordance with increasing the feeding level of FVM (p<0.05). In conclusion, our data indicated that the supplementation of high level of FVM could inhibit the Salmonella in caecum and reduce the emission of fecal $NH_3$ gas. Therefore, FVM at 5% level could be added in the diet of broiler chicks.

Effects of Dietary Flammulina velutipes Mycelium on Physico-chemical Properties and Nutritional Components of Chicken Meat (팽이버섯 균사체의 급여가 닭고기의 이화학적 특성과 영양성분에 미치는 영향)

  • Lee, Sang-Bum;Kim, Ji-Hee;Jeong, Su-Youn;Wang, Tao;Cho, Seong-Keun;Shin, Teak-Soon;Kang, Han-Seok;Kim, Youn-Chil;Kim, Seon-Ku;Lee, Hong-Gu
    • Journal of Life Science
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    • v.23 no.7
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    • pp.893-903
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    • 2013
  • The purpose of this study was to evaluate the effects of dietary Flammulina velutipes mycelium (FVM) on physico-chemical properties and nutritional components of chicken meat. Ninety-six broiler chicks (HanHyup No. 3, Korea) were divided into four groups: control (basal diet), T1 (supplemented with 1% FVM), T2 (3%), and T3 (5%). Broiler chicks in each group were slaughtered at 7 weeks of age, and their breast and thigh meat were collected. Lightness ($L^*$) and yellowness ($b^*$) in the T2 and T3 groups were higher than in the control group (p<0.05). The loss of breast meat during cooking was increased in the T1, T2, and T3 groups, and the water-holding capacity of the breast meat was also decreased in these three groups (p<0.05). The water-soluble protein solubility was lower in the T1, T2, and T3 groups than in the control group (p<0.05), but the salt-soluble protein solubility in these three groups was higher than that in the control group (p<0.05). The crude fat content of the breast meat was decreased and that of the thigh meat was increased as the level of FVM was increased (p<0.05). The unsaturated fatty acid content of the breast meat was higher in the T2 and T3 groups than in the control group (p<0.05). The free amino acid content was high in the T1, T2, and T3 groups compared to the control. In conclusion, these results showed that feeding with 3% and 5% FVM increased the L and b values in thigh meat, improved the salt-soluble protein solubility, and increased the content of unsaturated fatty acids and free amino acids.

NUMERICAL SIMULATION OF TSUNAMI WITH VOF METHOD BASED ON FVM (FVM에 기초한 VOF법에 의한 쓰나미 수치해석)

  • Myong, Hyon Kook;Park, Jin Woo
    • Journal of computational fluids engineering
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    • v.19 no.4
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    • pp.52-60
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    • 2014
  • Recently, coastal structures have been built to protect coastal areas. However, if a tidal wave caused by an earthquake hits the coast, it would cause catastrophic damages. It is important to analyze the basics and the characteristics of a tsunami to reduce damages caused by natural disasters. In this study, a tsunami passing over different topographical changes is simulated with VOF method based on FVM(Finite Volume Method). The reduction of both scale and velocity is accomplished by similarity analysis, and an initial energy is generated by increasing the water level as needed to create a tsunami as if it is caused by a crustal movement. It is found that the present method is appropriate to simulate the tsunami with its mechanism.

A Study for Estimation of the Surface Temperature Rise Using the FVM and Semi-Infinite Solid Analysis (FVM과 반무한체 해석을 이용한 표면온도예측에 관한 연구)

  • 이상돈;김태완;조용주
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.11a
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    • pp.260-266
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    • 2001
  • The surface temperature at the interface of bodies in a sliding contact is one of the most important factors influencing the behavior of machine components. So the calculation of the surface temperature at a sliding contact interface has long been an interesting and important subject for tribologist. Several methods for calculating surface temperature have been devised. Several numerical methods have been used to predict the temperature rise of sliding surface. but those need much time to calculate. In this study to reduce the calculation time the hybrid method using both semi-infinite solid analysis and FVM was used. It is founded that the computing time of hybrid method was shorter than that of FVM.

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Numerical Simulation of friction Stir Spot Welding Process with AA5083-H18 (AA5083-H18 판재의 마찰 교반 점 용접 공정에 대한 전산 해석)

  • Kim, Don-Gun;Badarinarayan, Harsha;Ryu, Ill;Kim, Ji-Hoon;Kim, Chong-Min;Okamoto, Kazutaka;Wagoner, R.H.;Chung, Kwan-Soo
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.458-461
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    • 2009
  • Thermo-mechanical simulation of the Friction Stir Spot Welding (FSSW) processes was performed for the AA5083-H18 sheets, utilizing commercial Finite Element Method (FEM) and Finite Volume Method (FVM) which are based on Lagrangian and Eulerian formulations, respectively. The Lagrangian explicit dynamic FEM code, PAM-CRASH, and the Eulerian Computational Fluid Dynamics (CFD) FVM code, STAR-CD, were utilized to understand the effect of pin geometry on weld strength and material flow under the unsteady state condition. Using FVM code, material flow pattern near the tool boundary was analyzed to explain the weld strength difference between the weld by cylindrical pin and the weld by triangular pin, while the frictional energy concept using the FEM code had limitation to explain the weld strength difference.

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Analysis of the Radiative Heat Transfer in a Cylindrical Enclosure with Obstacles Using the Discrete Ordinate and Finite Volume Method (구분종좌표법 및 유한체적법을 이용한 장애물이 있는 원통형 밀폐공간에서의 복사열전달 해석)

  • Kim, Seong-Woo;Kim, Il-Kyoung;Kim, Woo-Seung
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.347-352
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    • 2000
  • In the present study, DOM and FVM have been used to analyze the radiative heat transfer in an axisymmetric cylindrical enclosure with obstacles. Heat flux distributions on the wall of enclosure form DOM and FVM are compared to those from simplified zone analysis for a nonparticipating medium. The comparison of DOM and FVM is also presented. Results show that there is a good agreement between FVM and simplified zone analysis. In addition, the effect of the thickness of the obstacle on the results is considered. Heat flux distribution on the surface of the obstacle is also presented.

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A Study on Fluid Flow Analysis of High Pressure Positive Displacement Pump without Clearance (클리어런스가 없는 초고압 회전용적형 헬리컬기어 펌프의 유동해석에 관한 연구)

  • Min, Se-Hong;Kim, Ho-Chul
    • Fire Science and Engineering
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    • v.29 no.2
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    • pp.33-38
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    • 2015
  • For the purpose of high-pressure and suction of fixed amount, the development of ultra-high pressure rotating helical gear positive displacement pump with no clearance had been proceeded. The CFD analysis was performed to verify the internal pressure and the discharge flow velocity of the pump. Accordingly, a flow analysis were performed by FVM technique and we were unable to obtain a successful result since the fluid domain is separated because the grid is not configured in a row in FVM flow analysis of the fully enclosed type without clearance. Because of these problems, the flow analysis was performed by MPS method which grid configuration is not needed and the internal pressure and the discharge flow velocity of the pump were confirmed through the MPS flow analysis. At 1,000 rpm rotation speed of the rotor, the minimum internal pressure of the pump was 19.5 bar, maximum pressure was 44.6 bar and average pressure was 33.9 bar. And the minimum discharge flow velocity was 64.5 m/s, maximum discharge flow velocity was 84.8 m/s and average discharge flow velocity was 76.1 m/s. Through this study, we could confirm that MPS method was more suitable than FVM method in terms of flow analysis with no clearance. In addition, the relationship of the flow velocity according to the change of ultra-high pressure rotating helical gear positive displacement pump could be identified through this study.

A Study on CO2 Emission Factor for Earth-Work Equipment Using C-FVM (C-FVM을 이용한 토공장비의 CO2 배출계수에 관한 연구)

  • Kim, Byung-Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.3
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    • pp.999-1006
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    • 2014
  • $CO_2$ emission factor for earthwork equipment was made based on fuel consumption quantity using IPCC carbon emission factor. This is presented through the carbon emission estimating guideline each facilities by the Ministry of Land, Infrastructure and Transportation in 2011. However, this method has the defect which don't apply the various condition of site. Therefor it needs the new emission factor supplemented these defects. This study will tries to estimate $CO_2$ emission with the direct measurement method using concentration flow velocity measurement (C-FVM) for earth work equipment and present the new $CO_2$ emission factor for earth work equipment after compare with emission factor of the Ministry of Land, Infrastructure and Transportation.

Numerical Simulation of Wave Forces acting on Fixed Offshore Structures Using Hybrid Scheme (하이브리드 기법을 이용한 고정된 해양구조물에 작용하는 파랑하중에 관한 수치 시뮬레이션)

  • Nam, Bo-Woo;Hong, Sa-Young;Kim, Yong-Hwan
    • Journal of Ocean Engineering and Technology
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    • v.24 no.6
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    • pp.16-22
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    • 2010
  • In this paper, the diffraction problems for fixed offshore structures are solved using a hybrid scheme. In this hybrid scheme, potential-based solutions and the Navier-Stokes-based finite volume method (FVM) with a volume-of-fluid (VOF) method are combined. We introduce a buffer zone for efficient wave-making and damping. In this buffer zone, the near field solution from FVM-VOF is gradually changed to Stokes' 2nd order wave solutions. Three different models, including the truncated cylinder, sphere, and wigleyIII model, are numerically investigated in regular waves with a wave steepness of 1/30. The efficiency and accuracy of the hybrid scheme are numerically validated from results using different domain sizes and buffer zones. The wave exciting forces from the FVM-VOF simulations are compared with experiments and potential-based solutions from the higher-order boundary element method (HOBEM). This comparison shows good agreement between the hybrid scheme and potential-based solutions.

Analysis of 1D and 2D Flows in Open-Channel with FDM and FVM (유한차분법과 유한체적법을 이용한 1차원과 2차원 개수로 흐름해석)

  • Kim, Man Sik;Lee, Jin Hee;Jeong, Chan;Park, Roh Hyuk
    • Journal of Wetlands Research
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    • v.10 no.2
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    • pp.67-79
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    • 2008
  • The one-dimensional (1D) finite-difference method (FDM) with Abbott-Ionescu scheme and the two-dimensional (2D) finite-volume method (FVM) with an approximate Riemann solver (Osher scheme) for unsteady flow calculation in river are described. The two models have been applied to several problems including flow in a straight channel, flow in a slightly meandering channel and a flow in a meandering channel. The uniform rectangular channel was employed for the purpose of comparing results. A comparison is made between the results of computation on 1D and 2D flows including straight channel, slightly meandering channel and meandering channel application. The implementation of the finite-volume method allows complex boundary geometry represented. Agreement between FVM and FDM results regarding the discharge and stage is considered very satisfactory in straight channel application. It was concluded that a 1D analysis is sufficient if the channel is prismatic and remains straight. For curved (meandering) channels, a 2D or 3D model must be used in order to model the flow accurately.

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