• 제목/요약/키워드: flow test

검색결과 6,521건 처리시간 0.039초

Experimental investigation of jet pump performance used for high flow amplification in nuclear applications

  • Vimal Kotak;Anil Pathrose;Samiran Sengupta;Sugilal Gopalkrishnan;Sujay Bhattacharya
    • Nuclear Engineering and Technology
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    • 제55권10호
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    • pp.3549-3558
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    • 2023
  • The jet pump can be used in a test device of a nuclear reactor for high flow amplification as it reduces inlet flow requirement and thereby size of the process components. In the present work, a miniature jet pump was designed to meet high flow amplification greater than 3. Subsequently, experiments were carried out using a test setup for design validation and performance evaluation of the jet pump for different parameters. It was observed that a minimum pressure of 0.6 bar (g) was required for the secondary fluid inside the jet pump to ensure cavitation free performance at high amplification. Spacing between the nozzle tip and the mixing chamber entry point had significant effect on the performance of the jet pump. Variation in primary flow, temperature and area ratio also affected the performance. It was observed that at high flow amplification, the analytical solution differed significantly from experimental results due to very large velocities encountered in the miniature size jet pump.

고유동콘크리트의 각종 유동특성에 미치는 세골재의 영향에 관한 실험적 연구 (An Experimental Study on the Fluidity of High Flowing Concrete Affected by Fine Aggregate Types)

  • 김규용;신홍철;최세진;강희관;조성현;김무한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.220-226
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    • 1997
  • High flowing concrete has flowability, passability, segregation resistance and so on, and there are so many influence factor to affect to fluidity of high flowing concrete, therefore it is so difficult to evaluate exactly the properties in fresh state. This study is to analyze and evaluate thefluidity of high flowing concrete affected by fine aggregate with test method such as, slump-flow test, V-lot test, L-flow test, Box filling test.

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21AFR 희박연료모듈의 저압 및 고압 연소성능시험 (Performance Test of 21AFR Lean Fuel Module at Low and High Operating Conditions)

  • 한영민;고영성;양수석;이대성
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.858-863
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    • 2001
  • In this paper, the test and result of flow and combustion for 21AFR lean fuel models are described. The necessity to develop the low emission combustor has been issued from the concern on the increase of green house and the destruction of ozone layer. To evaluate the flow and combustion performance of new designed 21AFR lean modules, the hydraulic tests in stereo lithographic airflows models, the low pressure combustion tests in three injectors model for weak extinction and ignition and the high pressure combustion tests in single sector for NOx, SAE and efficiency are performed. The low pressure tests reveal that the governing parameters in weak extinction and ignition at atmospheric condition are prefilmer length, swirl flow rotation direction, secondary swirl angle and flow split. As a results of combustion test at high pressure, the efficiency and smoke level are satisfied with performance targets, but EINOx of 17.8 is higher than target value of 13.1. The high pressure tests show that the main parameters influenced on NOx are primary swirl angle, swirl flow rotation direction, heatshield exit angle and liner mixing hole location.

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폐색으로 인한 부직포의 투수능 저하 현상 (Permeability Reduction of Geotextile Filters Induced by Clogging)

  • 이인모;김주현
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.481-488
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    • 2000
  • The mechanism of soil-geotextile system has been studied among researchers since the application of geotextile as a replacement of graded granular filters is rapidly growing. The interaction of soils with geotextile is rather complicated so that its design criteria are mostly based on empiricism. Hence, it is essential to study the characteristics of fine particles transport into geotextile induced by the groundwater flow In this study, the permeability reduction in the soil-filter system due to clogging phenomenon is evaluated. An extensive research program is performed using two typical weathered residual soils which are sampled at Shinnae-dong and Poi-dong area in Seoul. Two separate simulation tests with weathered residual soil are peformed: the one is the filtration test(cross-plane flow test): and the other is the drainage test(in-plane flow test). Needle punched non-woven geotextiles are selected since it is often used as a drainage material in the field. The compatibility of the soil-filter system is investigated with emphasis on the clogging phenomenon. The hydraulic behaviour of the soil-filter system is evaluated by changing several testing conditions.

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Development of cellulose nano beads based a rapid detection kit to detect staphylococcal enterotoxin B

  • Kim, Giyoung;Yoo, Jinyoung;Park, Saetbyeol
    • 농업과학연구
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    • 제46권3호
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    • pp.549-557
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    • 2019
  • Staphylococcal enterotoxin is a very common cause of food poisoning. Conventional detection methods for the toxin including enzyme-linked immunosorbent assays (ELISAs), chemiluminescence (ECL), and polymerase chain reaction (PCR) assays require a lot of time, efforts, and expert technicians. Lateral flow strip kits have shown great potential for the rapid detection of foodborne pathogens. The lateral flow strip kit is widely used in clinical settings because it is easy to use, fast, and cost effective. A typical lateral flow strip kit uses colloidal gold to generate a visual signal. However, the lateral flow strip kit based on colloidal gold has limited sensitivity to fulfill food safety regulation requirements. This study was performed to develop a rapid test kit for pathogenic staphylococcal enterotoxin B (SEB) in food samples. The rapid detection kit was fabricated based on a nitrocellulose lateral-flow strip. Cellulose nano beads and SEB antibodies were used as the tag and receptor, respectively, to improve the detection performance. Manually spotted SEB antibody and anti-rabbit antibody on the surface of the nitrocellulose membrane were used as test and control spots, respectively. The feasibility of the rapid test kit to detect SEB in samples was evaluated. The sensitivity of the kit was 10 ng/mL SEB spiked in PBS. Additionally, the rapid test kit could detect 1 ng/mL of SEB in chicken meat extract.

목 면적 변화에 따른 터빈노즐 내부 유동 특성에 관한 수치적 조사 (A NUMERICAL INVESTIGATION ON THE INTERNAL FLOW CHARACTERISTICS IN TURBINE NOZZLE BY VARIATION OF ITS FLOW AREA)

  • 김영철;강원태;신병록
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2010년 춘계학술대회논문집
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    • pp.584-585
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    • 2010
  • A numerical simulation was performed to investigate the internal flow characteristics in gas turbine nozzle by the variation of flow area of the nozzle. In general the area of turbine nozzle is chosen by the most substantial factor on performance improvement of turbine at the first stage. In the performances test through CFD analysis for three types of nozzle with conventional, enlarged and reduced area, reduced one with effective flow area (EFA) was the most efficient. That is the minimum effective value within EFA limit defined by the manual of technical order had a good performance. It is useful to avoid the low power problem in the test of performance after maintenance and overhaul of turbine engine.

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공기압실린더의 누설유량 계측에 관한 연구 (A Study on the Measurement Method of Leakage for Pneumatic Cylinder)

  • 장지성;지상원
    • 동력기계공학회지
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    • 제11권4호
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    • pp.98-102
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    • 2007
  • In this study, a measurement method of leakage flow-rate for pneumatic driving apparatus is proposed. The existing measurement methods of leakage flow-rate of air need disassemble the test component. Therefore, there is no effective method to measure the leakage flow-rate while operating pneumatic driving apparatus. In this study, the leakage flow-rate is measured from the pressure change in an isothermal chamber that can realize isothermal conditions by stuffing the steel wool into it. Therefore, a wide range of flow-rate could be measured only from the pressure response and the leakage flow-rate can be measured during operating pneumatic driving apparatus. The effectiveness of the proposed method is proved by experimental results.

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Lattice Boltzmann Equation 방법을 복잡한 형상의 채널 유동 해석에 적용하기 위한 수치적 연구 (The Numerical Study of Flow through Complicated-Channel with the Lattice Boltzmann Equation Method)

  • 정기호;하만영
    • 한국가시화정보학회지
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    • 제2권1호
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    • pp.46-51
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    • 2004
  • This paper deals with the evaluation of several boundary conditions which are commonly used in the lattice Boltzmann equation method. 2-D channel flow(Poiseuille flow) and lid-driven cavity flow was selected as a test problem of this study, because there exist an analytic solution and previous study which could be used for a benchmarking test. It was found that lattice Boltzmann method still needs more considerations of stability and physical consistency, though it could predict the flow patterns both qualitatively and quantitatively.

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Tomographic Reconstruction of a Three-Dimensional Flow Field with Limited Interferometric Data

  • Cha, Dong-Jin
    • International Journal of Air-Conditioning and Refrigeration
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    • 제8권2호
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    • pp.11-22
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    • 2000
  • Holographic interferometric tomography can provide reconstruction of instantaneous three-dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80$\circ$. The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.

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Lattice Boltzmann Equation 방법을 이용한 2차원 비압축성 유동 해석에 관한 수치적 연구 (The Numerical Study of 2-D incompressible flow with the Lattice Boltzmann Equation method)

  • 정기호;하만영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1875-1879
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    • 2004
  • This paper deals with the evaluation of several boundary conditions which are commonly used in the lattice Boltzmann equation method. 2-D channel flow(poiseui1le flow) and lid-driven cavity flow was selected as a test problem of this study, because there exist an analytic solution and previous study which could be used for a benchmarking test. It was found that lattice Boltzmann method still needs more considerations of stability and physical consistency, though it could predict the flow patterns both qualitatively and quantitatively.

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