• Title/Summary/Keyword: Fluent modeling

Search Result 64, Processing Time 0.025 seconds

Study on K-factor for temperature variation of working fluid in spray nozzle with orifice (오리피스형 분사노즐에서 작동유체의 온도변화에 따른 K-factor에 관한 연구)

  • Bae, K.Y.;Chung, H.T.;Kim, C.H.;Kim, H.B.
    • Journal of Power System Engineering
    • /
    • v.12 no.3
    • /
    • pp.12-18
    • /
    • 2008
  • In the present study, the numerical simulation has been performed to investigate K-factor for temperature variation of working fluid in spray nozzle with orifice. The commercial CFD software, Fluent with the proper modeling was applied for analyzing the internal of the spray nozzle. Numerical result for K-factor at $20^{\circ}C$ agrees with the experimental result that it applied n=0.5 within about 7% error. The pressure drop inside nozzle is showed 20% passing swirler, 70% in the region between the outlet of swirler and the orifice and 10% at the outlet of orifice. As the operating pressure is increased, K-factor is decreased by effect of flow resistance at it's inlet before pass swirler. The temperature increase of working fluid reduced the flow rate according to reducing of density, and average 1.23% decrease is showed in the present research.

  • PDF

Time Lag Analysis Using Phase of Flame Transfer Function (화염전달함수의 위상차를 이용한 시간지연 분석)

  • Pyo, Yeongmin;Kim, Jihwan;Kim, Daesik
    • Journal of ILASS-Korea
    • /
    • v.21 no.2
    • /
    • pp.104-110
    • /
    • 2016
  • Main purpose of the current paper is to show results of time lag analysis using phase information of flame transfer function in order to predict combustion instabilities in a gas turbine combustor. The flame transfer function (FTF) is modeled using a commercial Computational Fluid Dynamics (CFD) code (Fluent). Comparisons of the modeled flame shapes with the measured ones were made using the optimized heat transfer conditions and combustion models. The FTF modeling results show a quite good agreement with the measurement data in predicting the phase delay (i.e. time lag). Time lag analysis results using the phase of FTF shows better combustion instability prediction accuracy than using time lag calculated from the steady state flame length.

APPLICATION OF CFD TECHNIQUE TO PERFORMANCE PREDICTION OF SPRAY CHARACTERISTICS OF WATER-MIST FIRE SUPPRESSION NOZZLES (미분무수 소화 노즐의 분무 특성 예측을 위한 CFD기법의 적용)

  • Chung, H.T.;Lee, C.H.;Cho, B.I.;Han, Y.S.;Ock, Y.W.
    • Journal of computational fluids engineering
    • /
    • v.11 no.4 s.35
    • /
    • pp.56-61
    • /
    • 2006
  • Numerical simulation has been performed to investigate the characteristics of the mist flow through the fire suppression nozzles. The commercial CFD software, FLUENT with the proper modeling was applied for analyzing both the internal and external flow of the spray nozzles. Computations were made for the full cone nozzle in the operation range of the low pressure and high flow-rate. To validate the present computational procedure, numerical results are compared with measurements in terms of K-factor, SMD, axial spray velocity and spray angles. Numerical results suggested that the present numerical model can be used as an adequate tool for a design purpose of mist-spray nozzles.

Numerical Analysis of Flow Path inside the Feedwater Valve (급수밸브 내부의 유동경로 수치해석)

  • Kwag, Seung-Hyun;Won, Yong-Hee
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 2006.11a
    • /
    • pp.416-419
    • /
    • 2006
  • Numerical analysis is carried out to identify the wall thinning effect inside the feed water valve. The finite volume method is applied to make analysis for the viscous flows. The commercial cock FLUENT is used for the simulation and the GAMBIT for the grid generation. The RNG $\kappa-\varepsilon$ model is used for the turbulence and the tet-hybrid grid is applied for the modeling. The velocity vector, the pressure contour, the change of residual along the iteration number, and the dynamic head are predicted for the hydrodynamic investigation.

  • PDF

Performance and flow field assessment of settling tanks using experimental and CFD modeling

  • Nouri, Alireza Zamani;Heydari, Mohammad Mehdi
    • Membrane and Water Treatment
    • /
    • v.8 no.5
    • /
    • pp.423-435
    • /
    • 2017
  • Settling Basins are one of the most important and popular methods for removal of suspended sediments irrigation and drainage networks or power canals taking off from an alluvial river and wastewater treatment plant. Improving the performance and so increasing sediment removal efficiency of settling basins by an alternative method is necessary. In the present work, the effect of baffle and its angle of attack with the flow (${\theta}$) on the sediment removal efficiency is investigated by conducting a series of experiments on a straight canal with 8 m length, 0.3 m width and 0.5 m height and 3 m length of basin equipped with an adjustable glass baffle. A numerical analysis has been carried out using ANSYS Fluent 3D software (a general purpose computational fluid dynamics simulation tool) for three Froude numbers from the experiments. The numerical and experimental results were found to match reasonably well.

Application of CFD Technique to Performance Prediction of Spray Characteristics of Fire Suppression Nozzles (소화 노즐의 분무 특성 예측을 위한 CFD 기법의 적용)

  • Chung, H.;Lee, C.;Jung, H.;Choi, B.;Han, Y.;Ohck, Y.
    • 유체기계공업학회:학술대회논문집
    • /
    • 2005.12a
    • /
    • pp.233-239
    • /
    • 2005
  • In the present study, numerical simulation has been performed to investigate the characteristics of the mist flow through the fire suppression nozzles. The commercial CFD software, FLUENT with the proper modeling was applied in both the internal and external flow region of the spray nozzles. Applications were done to the full cone nozzle for the operation range of the low pressure and high flow-rate. Numerical validation was proved by the comparison of the experimental data. Parametric study of the key design factors was tried to improve the performance.

  • PDF

Experimental and Numerical Investigation for NOx Reduction with Fuel Lean Reburning System (NOx저감을 위한 연료희박 재연소 기법의 실험 및 수치적 연구)

  • Kim, Hak-Young;Baek, Seung-Wook;Son, Hee;Kim, Se-Won
    • Journal of the Korean Society of Combustion
    • /
    • v.14 no.2
    • /
    • pp.18-25
    • /
    • 2009
  • Fuel lean reburning method is very attractive way in comparison with conventional reburning method for reducing NOX. Meanwhile, the knowledge of the how flue gas re-circulated, temperature distribution and species concentration is crucial for the design and operation of an effective fuel lean reburning system. For this reason, numerical analysis of fuel lean reburning system is a very important and challenge task. In this work, the effect of fuel lean reburn system on NOX reduction has been experimentally and numerically conducted. Experimental study has been conducted with a 15kW lab scale furnace. Liquefied Petroleum Gas is used as main fuel and reburn fuel. To carry out numerical study, the finite-volume based commercial computational fluid dynamics (CFD) code FLUENT6.3 was used to simulate the reacting flow in a given laboratory furnace. Steady state, three dimensional analysis performed for turbulent reactive flow and radiative heat transfer in the furnace.

  • PDF

Flow analysis of fermenter, digester and dryer environmental in energy facilities (환경 에너지 시설 내 발효조, 소화기 및 건조기 유동해석)

  • Jeon, Yong-Han
    • Design & Manufacturing
    • /
    • v.13 no.4
    • /
    • pp.28-33
    • /
    • 2019
  • In this study, the flow analysis of fermentation tank, digester and dryer, which are the main equipment in environmental energy facilities, was carried out. Numerical analysis was carried out with the size of the actual plant, and 3D modeling program CATIA V5 R16, grid generation program Gambit, and general purpose flow analysis package ANSYS-FLUENT (v13) were used. Simulation results of the carrier gas flow analysis in the STD dryer using the computational fluid dynamics program showed that the carrier gas smoothly circulated between the shells of the dryer and the flow was uniformly distributed without stagnation or flow. It is also predicted that rotational flow due to shell rotation is active. The average flow velocity of carrier gas in the STD dryer was estimated to be about 0.196m / s, and the average temperature of the carrier gas was calculated to be 424K. Due to the relatively slow carrier gas velocity and high average temperature, the water content of the sludge can be effectively lowered.

Design of Centrifugal Impeller for Passenger Car by Flow Field Analysis (유동장 해석을 통한 승용차 원심 회전차의 형상 설계)

  • Lee, Dong-Ryul
    • Journal of the Korean Society of Mechanical Technology
    • /
    • v.13 no.3
    • /
    • pp.49-55
    • /
    • 2011
  • For the purpose of the enhancement of the air conditioner performance and fuel effciency, several cases of centrifugal impeller for passenger car air conditioner have been numerically analyzed by changing central angle of blades and length of outlet for shape optimization of the impeller. Commercial CFD program Fluent 6.3.26 has been used to compute velocity, temperature, pressure and turbulence intensity that can lead numerous results. The central angles of two blades and three cases of outlet length led 4~12% and 3.5~6.4% differences of velocity and flow rate, respectively. The velocity distribution near the blade surface was axisymmetric and had a maximum value of 22.19 m/s and velocity of the vertical direction of the impeller showed linear increase with horizontal direction. At case 3 of oultet length, there existed a a minimum pressure value of -133320 Pa.

Consequence Analysis for Accidental Gas Release in Labs (실험실 가스 누출 시 피해 영향 분석)

  • Jang, Yuri;Jung, Seungho;Park, Kyoshik
    • Journal of the Korean Institute of Gas
    • /
    • v.19 no.4
    • /
    • pp.29-34
    • /
    • 2015
  • Accidents in laboratory dealing with chemicals have constantly occurred. In the case of a gas explosion or an accident related to leakage of chemical materials, the damage is much greater, thereby leading to a serious accident. Especially, the safety of laboratory in University is important because students build up knowledge and skills and accumulate experience as the main researchers. In this paper, 5 gases(CO, $NH_3$, $H_2$, $CH_4$, $N_2$) are selected to model since they are often used in university laboratories. From the scenarios where the gases are released, the diffusion process is estimated and analyzed to predict damage degree by PHAST v.6.7. Internal diffusion process is modeled through FLUENT which is Computational Fluid Dynamics(CFD) tool. Also, we compare indoor damage with outdoor one when discharged to the outside through the laboratory's window. In the modeling results, the outdoor damages for accident scenarios in the results are far less than then of real plants since the vessel usually used in laboratory(i.e. the capacity of the cylinder; 47 L or less) is significantly less than workplace's one(using ton measure). However as shown in the results small amount can have high consequences for indoor accidents.