• Title/Summary/Keyword: Computer Fluid Dynamics

Search Result 191, Processing Time 0.029 seconds

Flow Analysis of the Tube Type Marine Auto-Backwashing Fuel Oil Filter (튜브형 박용 자동역세 연료유 필터 내부의 유동해석)

  • Yang, Jang-Sik;Kim, Bong-Hwan;Park, Young-Bum
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.33 no.4
    • /
    • pp.578-587
    • /
    • 2009
  • In this paper, the characteristics of incompressible flow in a tube type marine fuel oil filter have been investigated. Fluent program has been used to obtain the solutions for the problems of three-dimensional, turbulent fuel oil flow in a filtering system. The inlet flow field is assumed to be uniform. The velocity and pressure distributions were obtained using Darcy's law. The increase of inlet velocity for cleaning fuel oil may cause some problems like vibration of the filter element. It was also required to consider the distribution of cleaning velocity because the worst distribution of cleaning velocity may cause the local insufficient cleaning effect and furthermore the effective filtration area can be reduced. The simulated results show that the computer code can be successfully applied for simulation of the complex base oil flow through the porous media. This paper could be applied to the design of auto-backwashing filtering system as design factor.

Evaluation of Indoor Air Environment by Changing Diffuser Location and Air Temperature with Under Floor Air Conditioning System (바닥취출 및 흡입시스템 공조방식에서 취출조건 변경시 실내공기환경 평가)

  • Kim Se-hwan;Park Jong-Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.17 no.5
    • /
    • pp.397-403
    • /
    • 2005
  • The thermal comfort of occupants is directly related to several environmental factors such as velocity of air flow, turbulence intensity and temperature distribution of indoor air. The purpose of this study is to evaluate the indoor air flow and temperature distribution in office area using under-floor air-conditioning system (UFAC System) based on the results from physical measurements and to perform a Computer Fluid Dynamics (CFD) under the same condition of inlet and outlet as field measurement. The results from the CFD simulation are similar to those from the field measurement. The results show that UFAC system is provide proper indoor condition for occupants.

The estimations of planing hull running attitude and resistance by using CFD and Goal Driven Optimization

  • ZHANG, Qi;KIM, Dong-Joon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.51 no.3
    • /
    • pp.285-294
    • /
    • 2015
  • As a "kind of" mature ship form, planing hull has been widely used in military and civilian areas. Therefore, a reasonable design for planing hull becomes more and more important. For planing hull, resistance and trim are always the most important problems we are concerned with. It affects the planing hull's economic efficiency and maneuverability very seriously. Instead of the expensive towing tank experiments, the development of computer comprehensive ability allows us to previously apply computational fluid dynamics(CFD)to the ship design. In this paper, the CFD method and Goal Driven Optimization (GDO) were used in the estimations of planing hull resistance and running attitude to provide a possible method for performance computation of planing hull.

A Study on Parameter Estimation for General Aviation Canard Aircraft

  • Kim, Eung Tai;Seong, Kie-Jeong;Kim, Yeong-Cheol
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.16 no.3
    • /
    • pp.425-436
    • /
    • 2015
  • This paper presents the procedures used for estimating the stability and control derivatives of a general aviation canard aircraft from flight data. The maximum likelihood estimation method which accounts for both process and measurement noise was used for the flight data analysis of a four seat canard aircraft, the Firefly. Without relying on the parameter estimation method, several aerodynamic derivatives were obtained by analyzing the steady state flight data. A wind tunnel test, a flight test of a 1/4 scaled remotely controlled model aircraft, and the prediction of aerodynamic coefficients using the USAF Stability and Control Digital Data Compendium (DATCOM), Advanced Aircraft Analysis (AAA), and Computer Fluid Dynamics (CFD) were performed during the development phase of the Firefly and the results were compared with flight determined derivatives of a full scaled flight prototype. A correlation between the results from each method could be used for the design of the canard aircraft as well as for building the aerodynamic database.

Heat Dissipation Designs for LED Backlight System; Simulation and Experiment

  • Chiu, Tien-Lung;Tseng, Wet-Yang;Chien, Chin-Cheng;Lo, Wei-Yu;Ting, Chu-Chi;Chang, Chia-Yuan;Chang, Chao-Jen;Sun, Oliver
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.522-524
    • /
    • 2005
  • The LED light source has many excellent advantages for the application of LCD backlight module. As we know, the operational temperature can significantly influence the characteristics of LEDs. Heat can damage the LED 's quality, and decrease its lifetime and output light intensity. In this paper, we perform computer software, Flomerics CFD (Computational Fluid Dynamics), to simulate heat distribution of the 20.1" LED backlight module we designing, and realize how the different heat sinks can solve the serious heat problem in practice.

  • PDF

The Study on Performance in Underfloor Air Distribution(UFAD) Systems using Simulator (시뮬레이터를 이용한 바닥급기시스템의 성능에 관한 연구)

  • Yu, Ji-Yong;Jeong, Cha-Su;Cho, Dong-Woo;Yu, Ki-Hyung;Kim, Dong-Hee;Seo, Jung-Seok
    • Proceedings of the SAREK Conference
    • /
    • 2005.11a
    • /
    • pp.211-216
    • /
    • 2005
  • The authors carried out experiment, Computer Fluid Dynamics(CFD) and energy simulation of simulator. As a results of experiment and CFD, diffuser velocity is very important design factor for occupied zone air conditioning in Under Floor Air Distribution(UFAD) system. Then, in contrast to energy consumption of the Overhead system, the UFAD system could reduce 6.4% of the total energy because of occupied tone air conditioning. It concluded that tile UFAD system is more effective in energy Performance than the Overhead system.

  • PDF

A Numerical Study on Flow-Accelerated Corrosion in Two Adjacent Elbows

  • Yun, Hun;Hwang, Kyeongmo;Moon, Seung-Jae
    • Corrosion Science and Technology
    • /
    • v.15 no.1
    • /
    • pp.6-12
    • /
    • 2016
  • Flow-Accelerated Corrosion (FAC) is a well-known degradation mechanism that attacks the secondary piping in nuclear power plants. Since the Surry Unit 2 event in 1986, most nuclear power plants have implemented management programs to deal with damages in carbon and low-alloy steel piping. Despite the utmost efforts, damage induced by FAC still occurs in power plants around the world. In order to predict FAC wear, some computer programs were developed such as CHECWORKS, CICERO, and COMSY. Various data need to be input to these programs; the chemical composition of secondary piping, flow operating conditions and piping geometries. CHECWORKS, developed by the Electric Power Research Institute (EPRI), uses a geometry code to calculate geometry effects. Such a relatively simple geometry code is limited in acquiring the accuracy of FAC prediction. Recently, EPRI revisited the geometry code with the intention of updating it. In this study, numerical simulations were performed for two adjacent $90^{\circ}$ elbows and the results were analysed in terms of the proximity effect between the two adjacent elbows.

Study on Design of high Efficient Cooling System for Low Temperature Furnace in Semiconductor Processing (반도체 공정용 저온 열처리로의 고효율 냉각시스템 설계에 관한 연구)

  • Jeoung, Du-Won;Suh, Ma-Son;Kim, Kwang-Sun
    • Journal of the Semiconductor & Display Technology
    • /
    • v.9 no.4
    • /
    • pp.71-76
    • /
    • 2010
  • According to recent changes in industry for semiconductor devices, a low-temperature treatment has become a necessity. These changes relate to size refinement and the development of new materials. While variation in cooling efficiency does not affect the yield when using a high-temperature treatment, uniform cooling efficiency is necessary avoid "inconsistencies/bends" in low temperature treatments. However it is difficult to increase temperature stabilization in low temperature treatments. In this paper, using CFD (Computer Fluid Dynamics), we analyze and manipulate the design and input of the low-temperature system to attempt to control for temperature variations within the quartz tube, of which airflow appears to be a predominant factor. This simulation includes variable inputs such as airflow rate, head pressure, and design manipulations in the S.C.U. (Super Cooling Unit).

OpenFOAM : Open source CFD in research and industry

  • Jasak, Hrvoje
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.1 no.2
    • /
    • pp.89-94
    • /
    • 2009
  • The current focus of development in industrial Computational Fluid Dynamics (CFD) is integration of CFD into Computer-Aided product development, geometrical optimisation, robust design and similar. On the other hand, in CFD research aims to extend the boundaries of practical engineering use in "non-traditional" areas. Requirements of computational flexibility and code integration are contradictory: a change of coding paradigm, with object orientation, library components, equation mimicking is proposed as a way forward. This paper describes OpenFOAM, a C++ object oriented library for Computational Continuum Mechanics (CCM) developed by the author. Efficient and flexible implementation of complex physical models is achieved by mimicking the form of partial differential equation in software, with code functionality provided in library form. Open Source deployment and development model allows the user to achieve desired versatility in physical modeling without the sacrifice of complex geometry support and execution efficiency.

Series Solution of High Order Abel, Bernoulli, Chini and Riccati Equations

  • Henk, Koppelaar;Peyman, Nasehpour
    • Kyungpook Mathematical Journal
    • /
    • v.62 no.4
    • /
    • pp.729-736
    • /
    • 2022
  • To help solving intractable nonlinear evolution equations (NLEEs) of waves in the field of fluid dynamics we develop an algorithm to find new high order solutions of the class of Abel, Bernoulli, Chini and Riccati equations of the form y' = ayn + by + c, n > 1, with constant coefficients a, b, c. The role of this class of equations in NLEEs is explained in the introduction below. The basic algorithm to compute the coefficients of the power series solutions of the class, emerged long ago and is further developed in this paper. Practical application for hitherto unknown solutions is exemplified.