• 대한설비공학회지:설비저널
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• 제15권1호
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• pp.87-96
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• 1986

An experiment on the devices that enchance the stratification of storage tanks in a solar heat ins system has been carried out. The benefits of thermal stratification in sensible heat storage are to increase the system performance such as the collector efficiency or the fraction of the total load supplied by solar energy. Using the diffuser and the distributor as the stratification enchancement device, the expeliments were perfomed in the different condition of diameter and material of the distributor. As a result of experiments, there exists the diameter of distributor in which the stratification is made maximum under certain design and operation condition. Also it was identified that the kind of distributor material influenced the degree of stratification. Comparing the experimental result to the computational results calculated under the same conditions, the node number N(stratification index) was determined. The results of computer simulation that was performed about the actual solar heating system in Seoul for 24 hours show the relative advantage of stratified over well-mixed storage and the significant improvements in system performance.

• 펄프종이기술
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• 제35권5호
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• pp.37-45
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• 2003

To investigate the influence of the design and operating parameters of the headbox on hydrodynamics, a pilot headbox system and pressure monitoring apparatus were constructed. The pilot headbox system consisted of a circulating water reservoir, centrifugal pump, distributor, turbulence generator and slice. The distributor was designed to function as a pressure attenuator. Flow rate to the headbox and MD and CD velocity profiles in the slice zone were monitored using an ultrasonic flowmeter and Pitot tubes, respectively. As the distance from the step diffusor increased, evener CD velocity profile was observed. Wall effect increased with the increase of the velocity. Flow stability in the headbox was evaluated by injecting a dye at the outlet of the distributor. Application of theoretical analysis based on CFD in designing headboxes is briefly discussed.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Pre-symposium of the 10th ISWPC Recent Advances in Paper Science and Technology
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• pp.381-385
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• 1999

To investigate the influence of the design and operating parameters of the headbox on hydrodynamics, a pilot headbox system and pressure monitoring apparatus were constructed. The pilot headbox system consisted of a circulating water reservoir, centrifugal pump, distributor, step diffusor and slice. The distributor was designed to function as a pressure attenuator. Flow rate to the headbox and MD and CD velocity profiles in the slice zone were monitored using an ultrasonic flowmeter and Pitot tubes, respectively. As the distance from the step diffusor increased, evener CD velocity profile was observed. Wall effect increased with the increase of the velocity. Flow stability in the headbox was evaluated by injecting a dye at the outlet of the distributor. Application of theoretical analysis based on CFD in designing headboxes is briefly discussed.

• 태양에너지
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• 제11권2호
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• pp.34-40
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• 1991

Thermal stratification enhancement for the higher extraction efficiency of hot water storage tank was experimentally studied with transparent fiber glass cylindical tank($350{\ell}$, D=516mm, H=1680mm). Height to diameter ratio (H/D =1,2,3), flow rate(Q= 8,10,12LPM), inlet-outlet temperature differences(${\Delta}T=20,25,30^{\circ}C$), and geometry of inlet-outlet port were the parameters. In particular, three kind of distributors were used for geometry of inlet-outlet port. As a result, it was possible to get extraction efficiency of 95% by using the distributor having variable diameter but keeping a constant diameter of perforation. So it is recommendable to design the distributor so that the main pipe decrease in diameter toward the dead end.

• 대한지리학회지
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• 제41권4호
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• pp.507-512
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• 2006

일본 아키다 현 요코테 분지의 로쿠고 선상지에서 운용되고 있는 원통형 사이펀 방식 분수공에 대하여 소개하였다. 이 분수공은 급수구역 면적을 기준으로 180개의 오리피스와 정류판을 이용하여 매우 정확하게 관개용수를 분배하는 시설로서 선상지 지역주민의 물에 대한 집념을 엿볼 수 있다. 현재 시설의 기능적 가치는 점차 저하하고 있으나 지역성을 보여주는 상징적 경관으로서 또한 관광 자원으로서 가치가 새롭게 대두되고 있다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.53-59
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• 1995

In a hot water extraction process, the flow pattern of upper region in a storage tank is a major reason of mixing between hot water and cold water. In this study, the temperature distribution in a storage tank was measured to predict the flow pattern of upper region, and the degree of stratification was analysed to the variables dominating a extraction process. And also, it was found that the degree of stratification improved expecially in a low flow rate in case of using modified distributor I(DMI) as a outlet port type.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.188-192
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• 2006

This study is conducted to improve efficiency of thermal storage tank. The thermal storage tank was designed to store heat energy that obtained from solar or the others heat sources. However, it has difficulties in storing heat with uniform temperature through the entire tank with respect to vertical direction. This kind of maldistribution of the supplied heat to the storage tank effects on the system performance. In this study is focused on utilization of the thermal stratification to improve thermal comfort for people in the house. To enhance temperature stratification of the tank, a distributor was designed and Installed in the middle of the tank. The distributor is supplies hottest water to the top side of the tank which is very close to inlet of the supply line to the heating load. The hottest water that is accumulated on top side of the tank is firstly supplied to the load with higher temperature. Reminder water takes a little time to warming up until desired supply temperature reached. This kind alternating selection of the supply temperature is improve thermal comfort with moderated system performance.

• 한국물환경학회지
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• 제20권1호
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• pp.86-92
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• 2004

Lab-scale experiments have been carried out to investigate ammonia stripping with a modified spray tower for removing ammonia nitrogen from swine wastewater. The operating conditions such as initial pH, temperature, air flow, hole size of distributor determining the diameter of water drops, and influent solids concentration were closely examined focusing on removal efficiency of ammonia. As a result of the experiment, in order to achieve high rate of ammonia removal by the air stripping system, the air flow rate must be supplied at high rate with sufficiently high initial pH, temperature. The optimum operating condition to meet the residual ammonia concentration of 300 mg/L was the initial pH of 11.0 at $35^{\circ}C$ with the air flow rate of 20 L/min. It also showed that the smaller hole size is, the higher removal rate of ammonia is expected. However, when used a small sized distributor (2 mm), the flooding problem at the upper column occurred due to clogging of the hole. With regard to the influent solids concentration, it was showed that the lower concentration of solids, the higher removal rate of ammonia. The removal of particulate materials in influent led to improve the removal efficiency of ammonia, rather than to control the operating condition including initial pH, temperature, and air flow. The empirical correlation between KLa and operating parameters would be driven as, $K_{La}=(0.0003T-0.0047){\cdot}G^{0.3926}{\cdot}L^{-0.5169}{\cdot}C^{-0. 1849}$. The calculated $K_{La}$ from proposed formula can be used effectively to estimate the optimum reaction time and to calculate the volume of modified spray tower system.

• 한국태양에너지학회 논문집
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• 제22권2호
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• pp.11-17
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• 2002

This paper is concerned with the development of a new method for making, separating ice and storage floated ice by installing an evaporation plate at under-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating an ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. Developed new harvest-type method shows good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, however these components are not necessary in a new method. In this study ice storage systems are experimentally investigated to study the charge and discharge of thermal energy. The results show the applicable possibility and performance enhancement of a new type.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.268-273
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• 2001

A fundamental study on the harvest-type ice storage system applied ice making method in-water and its temperature characteristics in ice storage system was performed experimentally of the charge and discharge of cold. This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks.