• 동력기계공학회지
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• 제18권3호
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• pp.79-86
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• 2014

Mixed convective vortex flow in the three-dimensional rectangular channel filled with high viscous fluid(Pr=909) is investigated computationally under various operating conditions. The Reynolds number is varied from 0 to $5{\times}10^{-1}$, the Rayleigh number from $10^3$ to $5{\times}10^4$. The three-dimensional governing equations are discretized using the finite volume method. The effects of Reynolds number and Rayleigh number are presented and discussed. From a parametric study, it is found that vortex flow pattern of mixed convection in rectangular channels can be classified into three flow patterns basically, but the new vortex flow structures containing wave rolls are found, which are affected by Rayleigh number and Reynolds number. From this results, we can draw a flow regime map to delineate various vortex flow patterns in the high viscosity fluid mixed convective flow.

• 동아시아식생활학회지
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• 제25권3호
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• pp.440-450
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• 2015

Effects of Doenjang and Chunggukjang on rheological properties of bread flour were investigated based on falling number, RVA, farinogram, colorimeter, rheofermentometer and SEM. The falling number of bread flour was highest among all samples, and mixed flours containing Chunggukjang showed lower falling number than Doenjang. RVA showed that initial pasting temperatures of the control mixed flour of Doenjang and Chunggukjang increased sequentially, whereas peak viscosities were reversed and final viscosities showed similar results. In the farinogram, consistencies and water absorptions decreased with increasing quantity of Doenjang and Chunggukjang. Developments, stabilities, time to breakdowns and farinogram quality numbers of the mixed flour containing Doenjang were higher than those of Chunggukjang and greater addition decreased values. In the rheofermentometer test, height of maximum dough development of mixed flours containing Chunggukjang were lower than that of flours containing Doenjang. Total volumes, retention volumes and retention coefficients of mixed flours containing Doenjang and Chunggukjang were lower compared to the control. For features, SEM showed that mixed flour containing Chunggukjang showed a faded boundary compared to flour containing Doenjang. All of results showed that the various activities of Chunggukjang were more potent than those of Doenjang.

• 동력기계공학회지
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• 제10권2호
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• pp.29-35
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• 2006

Two-dimensional numerical simulation has been performed to investigate mixed convection heat transfer between inclined parallel plates with bottom-heated and top-cooled uniformly. The ratio of parallel plate length to height is 9.33, Prandtl number is 909(that of silicone oil at 298K) and Rayleigh number is 8600. In the ranges of the Reynolds number Re from 0 to 1.8 and the angle of inclination ${\theta}$ from 0 to 90 degree. The governing equations are discretized using the finite volume method. In this study, the effects of the Reynolds number, the angle of inclination, and the local and mean Nusselt numbers are presented and discussed. It is found that the periodic flow of mixed convection between inclined parallel plates is shown at $0^{\circ}{\leq}\;{\theta}<30^{\circ},\;Re<0.063$, and the flow pattern can be classified into three patterns which depend on Reynolds number and the angle of inclination. The minimum average Nusselt numbers occur at Re=0.05 regardless of the angle of inclination.

• 대한수학회보
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• 제58권6호
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• pp.1341-1354
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• 2021

Let r ≥ 2, and let k_i ≥ 2 for 1 ≤ i ≤ r. Mixed van der Waerden's theorem states that there exists a least positive integer w = w(k₁, k₂, k₃, …, k_r; r) such that for any n ≥ w, every r-colouring of [1, n] admits a k_i-term arithmetic progression with colour i for some i ∈ [1, r]. For k ≥ 3 and r ≥ 2, the mixed van der Waerden number w(k, 2, 2, …, 2; r) is denoted by w₂(k; r). B. Landman and A. Robertson [9] showed that for k < r < $\frac{3}{2}$(k - 1) and r ≥ 2k + 2, the inequality w₂(k; r) ≤ r(k - 1) holds. In this note, we establish some results on w₂(k; r) for 2 ≤ r ≤ k.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.182-184
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• 1998

PCR was used for quantitative counting of Bifidobacterium spp. in a sample mixed with Lactobacillus acidophilus using two primer sets; one set for universal priming and the other set for Bifidobacterium specific priming. DNA products from two independent PCRs with DNA extracted from the mixed sample were found to be easily distinguishable from each other by agarose gel electrophoresis. The concentrations of PCR products correlated with the total number of bacteria and with the number of Bifidobacterium spp. present in the sample.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.272-275
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• 2003

A mixed analytical/numerical method is developed here to solve the low Reynolds number kepsilon turbulence model. In this method the advection-diffusion part is solved numerically, while the source terms are split into two parts: one part is solved analytically and the next is solved numerically.

• 한국언어정보학회지:언어와정보
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• 제14권2호
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• pp.85-101
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• 2010

This paper discusses mixed agreement triggered by hybrid pronouns. Hybrid pronouns considered in this paper show number discrepancy in that they are plural in form but singular in meaning. When predicates agree with these hybrid pronouns, the puzzle of number agreement arises: finite verbs show syntactic agreement, while predicate adjectives show semantic agreement. This is explained by three factors in grammar of agreement, the feature specification of agreement controllers, the types of agreement targets, and the Agreement Marking Principle that mediates the relation of two poles of agreement, controllers and targets.

• 설비공학논문집
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• 제7권2호
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• pp.207-216
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• 1995

Flow and heat transfer characteristics of mixed convection heat transfer in a rectangular en-closure with various outlets are numerically investigated. The parameters considered here include Reynolds number, Grashof number and the position of outlet. The results show streamlines, isotherms, Nusselt numbers, velocity and temperature distributions. It has been shown that as Reynolds number increases, the size of cell decreases at Re$\leq$100 and increases at Re>100 for $Gr=10^4$. There is a minimum size of cells at Re=100, $Gr=10^4$. The maximum mean Nusselt number occurs at Re=400, $Gr=10^4$ and one right outlet. The mean Nusselt numbers can be formulated by the correlation equation $Nu=C{\cdot}Gr^a{\cdot}Re^b$.

• 동력기계공학회지
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• 제13권5호
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• pp.11-17
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• 2009

A numerical study of unsteady mixed convection in a cavity with high viscous fluid is presented. Finite volume method was employed for the discretization and PISO algorithm was used for calculating pressure term. The parameters governing the problem are the Rayleigh number ($10^3\;{\leq}\;Ra\;{\leq}\;10^5$), the Reynolds number (0 < Re $\leq$ 1), and the aspect ratio (0.5 $\leq$ AR $\leq$ 2). The fluid used is silicon oil, a high prandtl number fluid, Pr = 909.1. The results show velocity vectors and temperature distributions. It is found that the periodic flows in a cavity are observed at very low Reynolds numbers, and the period of periodic flow decreases with increasing Reynolds and Rayleigh numbers, and increases with increasing aspect ratio. Also, the Reynolds number range of periodic flow increases with increasing Rayleigh numbers and aspect ratio.

• 대한기계학회논문집
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• 제18권12호
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• pp.3297-3304
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• 1994

Experimental investigation have been made to study the double-diffusive nature of convection of an initially stratified salt-water solution heated from below in a cylindrical cavity. The objective is to examine the process of mixed-layer formation, the flow phenomena, the heat transfer characteristics, and temperature and concentration distribution according to the changes in the effective Rayleigh number based on the reference height which represents the relation of temperature and concentration gradient. The types of initially formed flow pattern are categorized in three regimes depending on the effective Rayleigh number ; stagnant flow regime, single mixed-layer flow regime and successively formed multiple mixed-layer flow regime. The temperature and concentration profiles are both uniform in each layer due to convective mixing in the layered flow regime, but both linear in stagnant flow regime and single mixed-layer flow regime. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly. The layers expand by diffusion of concentration through the interface along with its random fluctuation.