• Title/Summary/Keyword: Outlet Shape Design

Search Result 92, Processing Time 0.032 seconds

Design optimization of the outlet holes for bone crystal growing with bioactive materials in dental implants: Part I. cross-sectional area

  • Lee, Yong Keun;Lee, Kangsoo
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.23 no.2
    • /
    • pp.67-75
    • /
    • 2013
  • In order to improve osseo-integration of a dental implant with bone crystal we studied an implant with holes inside its body to deliver bioactive materials based on a proposed patent. After bioactive material is absorbed, bone crystal can grow into holes to increase implant bonding in addition to surface integration. The larger cross section area of outlet holes showed the less values of the maximum stress, and the stress concentrations near the uppermost outlet holes were also reduced with an increasing number of outlet holes. The conclusion, that the uppermost outlet design improvement was most effective to reduce the stress concentration and improve the growth rate of bone crystal, could be drawn. After the design optimizations, Type 6-C had provided the best results in this study. The overall shape optimization studies on the shape, location, number, and so on, of the outlet holes, should be carried out further.

A Study on the Proper Location of Ventilation Outlets and Inlets in the Germ Free Pigs' Room (무균돈사내 급배기구의 적정위치설정에 관한 연구)

  • Kwon, Soonjung;Son, Deok-Young;Choi, Yoon-Ho
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.14 no.4
    • /
    • pp.39-46
    • /
    • 2008
  • Construction and operation of Germ Free Pigs' facilities are very expensive because pigs' rooms and other major rooms of the facility require germfree environments. Especially, running the HVAC system of aseptic facilities requires a lot of expenses. However, proper location and efficient shape of outlets/inlets for the ventilation of the room can reduce the excessive running cost. In order to do that, this study proposes alternative location and shape of ventilation outlets/inlets to the existing design pattern in germfree pigs' room. The design condition of this study is the maintenance of adequate temperature(24$^{\circ}C$, $NH_3$concentration level(below 1.5 ppm), and air stream speed(below .25m/sec) in the pigs' room for the summer and the winter together. As the Software Program, FLUENT(Ver. 6.2) has been used for the analysis of proposed ventilation patterns. In conclusion, wall inlets and ceiling inlet/outlet are advisable in summer, wall inlets and ceiling outlets is advisable in winter. As far as the shape is concerned, diffuser type for the ceiling outlet is desirable.

  • PDF

A COMPUTATIONAL ANALYSIS FOR OUTLET SHAPE DESIGN TO SUPPRESS FLOW RECIRCULATION IN A ROTATING-DISK CVD REACTOR (회전원판형 CVD 장치의 유동 재순환을 억제하는 출구부 형상 설계를 위한 전산해석)

  • Park, J.J.;Kim, K.;Kwak, H.S.
    • Journal of computational fluids engineering
    • /
    • v.18 no.4
    • /
    • pp.74-81
    • /
    • 2013
  • A numerical design analysis is conducted to search for an optimal shape of outlet in a rotating-disk CVD reactor. The goal is to suppress flow recirculation that has been found in a reactor having a sudden expansion of flow passage outside of the rotating disk. In order to streamline gas flow, the sidewall at which the flow in the Ekman layer is impinged, is tilted. The axisymmetric laminar flow and heat transfer in the reactor are simulated using the incompressible ideal gas model. For the conventional vertical sidewall, the flow recirculation forming in the corner region could be expanded into the interior to distort the upstream flow. The numerical results show that this unfavorable phenomenon inducing back flow could be dramatically suppressed by tilting the sidewall at a certain range of angle. The assessment of deviation in deposition rate based on the characteristic isotherm illustrates that the sidewall tilting may expand the domain of stable plug-like flow regime toward higher pressure. A physical interpretation is attempted to explain the mechanism to suppress flow recirculation.

Numerical study of fluid behavior on protruding shapes within the inlet part of pressurized membrane module using computational fluid dynamics

  • Choi, Changkyoo;Lee, Chulmin;Park, No-Suk;Kim, In S.
    • Environmental Engineering Research
    • /
    • v.25 no.4
    • /
    • pp.498-505
    • /
    • 2020
  • This study analyzes the velocity and pressure incurred by protruding shapes installed within the inlet part of a pressurized membrane module during operation to determine the fluid flow distribution. In this paper, to find the flow distribution within a module, it investigates the velocity and pressure values at cross-sectional and outlet planes, and 9 sections classified on outlet plane using computational fluid dynamics. From the Reynolds number (Re), the fluid flow was estimated to be turbulent when the Re exceeded 4,000. In the vertical cross-sectional plane, shape 4 and 6 (round-type protrusion) showed the relatively high velocity of 0.535 m/s and 0.558 m/s, respectively, indicating a uniform flow distribution. From the velocity and pressure at the outlet, shape 4 also displayed a relatively uniform fluid velocity and pressure, indicating that fluid from the inlet rapidly and uniformly reached the outlet, however, from detailed data of velocity, pressure and flowrate obtained from 9 sections at the outlet, shape 6 revealed the low standard deviations for each section. Therefore, shape 6 was deemed to induce the ideal flow, since it maintained a uniform pressure, velocity and flowrate distribution.

Design of a Pump-Turbine Based on the 3D Inverse Design Method

  • Chen, Chengcheng;Zhu, Baoshan;Singh, Patrick Mark;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
    • /
    • v.18 no.1
    • /
    • pp.20-28
    • /
    • 2015
  • The pump-turbine impeller is the key component of pumped storage power plant. Current design methods of pump-turbine impeller are private and protected from public viewing. Generally, the design proceeds in two steps: the initial hydraulic design and optimization design to achieve a balanced performance between pump mode and turbine mode. In this study, the 3D inverse design method is used for the initial hydraulic impeller design. However, due to the special demand of high performance in both pump and reverse mode, the design method is insufficient. This study is carried out by modifying the geometrical parameters of the blade which have great influence and need special consideration in obtaining the high performance on the both modes, such as blade shape type at low pressure side (inlet of pump mode, outlet of turbine mode) and the blade lean at blade high pressure side (outlet of pump mode, inlet of turbine mode). The influence of the geometrical parameters on the performance characteristic is evaluated by CFD analysis which presents the efficiency and internal flow results. After these investigations of the geometrical parameters, the criteria of designing pump-turbine impeller blade low and high sides shape is achieved.

Minimization of Cogging Force in a Stationary Discontinuous Armature Linear Permanent Magnet Motor at the Outlet Edge

  • Kim, Yong-Jae;Jung, Sang-Yong
    • Journal of Magnetics
    • /
    • v.16 no.3
    • /
    • pp.288-293
    • /
    • 2011
  • Generally, the discontinuous armature permanent magnet linear synchronous motor (PM-LSM) is composed by the stator block (accelerator, re-accelerator, and decelerator) and the free running section. However, the stationary discontinuous armature design involves the velocity variation of the mover during drive when the armature's non-installation part changes over to installation part as a result of the outlet edge of the armature. Therefore, we considered deforming the shape of the outlet edge at the armature and apply skew on the permanent magnet by displacing the two magnet segments of each pole. This paper presents the results of a three-dimensional (3-D) numerical analysis with a finite element method (FEM) of the force exerted by the outlet edge.

Shape Design of the 3-Way Valve used in Marine Diesel Engines (LDCL JWCS) by CFD Analysis (유동해석을 통한 선박용 디젤엔진(LDCL JWCS)의 3-Way Valve 형상 설계)

  • Hwang, Gi Ung;Kwak, Hyo Seo;Kim, Jae Yeol;Eom, Tae Jin;Kim, Chul
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.41 no.11
    • /
    • pp.1077-1084
    • /
    • 2017
  • Camshaft engines designed for constant engine loads have been applied to existing marine diesel engines. However, due to environmental regulations, electro-hydraulic servo mechanisms, which have a loaddependent cylinder liner jacket water cooling system (LDCL-JWCS), have been recently developed to individually control the temperature of the cylinders depending on the engine load. In this system, the 3-way valve, which prevents low temperature corrosion by reducing the temperature difference between the upper and lower parts of the cylinder, has been employed, but the outlet mass flow of the existing valve is low. In this study, the design of the internal shape of the 3-way valve was performed by analyzing the effects of the design parameters of the valve shape on the performance (i.e., the outlet mass flow rate and temperature). The proposed model was verified by comparing its performance to that of existing marine diesel engine valves.

Performance Characteristics of Double-Inlet Centrifugal Blower According to Inlet and Outlet Angles of an Impeller (임펠러 입출구각에 따른 양흡입 원심송풍기 성능특성)

  • Lee, Jong-Sung;Jang, Choon-Man
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.25 no.2
    • /
    • pp.191-199
    • /
    • 2014
  • Effects of design variables on the performance of a double-inlet centrifugal blower have been analyzed based on the three-dimensional flow analysis. Two design variables, blade inlet and outlet angles, are introduced to enhance a blower performance. General analysis code, ANSYS-CFX13, is employed to analyze internal flow and a blower performance. SST turbulence model is employed to estimate the eddy viscosity. Throughout the shape optimization of an impeller at the design flow condition, the blower efficiency and pressure are successfully increased by 4.7 and 1.02 percent compared to reference one. It is noted that separated flow observed near cut-off region can be reduced by optimal design of blade angles, which results in stable flow pattern in the blade passage and increase of a blower performance. The stable flow at the impeller also makes good effects at the outlet of a volute casing.

MULTI STAGE SHAPE OPTIMIZATION OF CENTRIFUGAL FAN FOR HOME APPLIANCE USING CFD (전산유체역학을 활용한 가전 제품용 원심팬 블레이드의 단계별 형상 최적화)

  • Kim, J.S.;Kang, T.G.
    • Journal of computational fluids engineering
    • /
    • v.21 no.3
    • /
    • pp.39-47
    • /
    • 2016
  • We conducted a multi-stage optimization to secure the desired performance of a centrifugal fan for home appliance in an early stage of product development. In optimization, the static pressure at the outlet of the fan is chosen as an objective function that is to be maximized, providing the required flow rate at the operating point of the fan. The optimization procedure begins with parameters for an initial baseline fan design. The baseline design is optimized by using a commercial optimization package. Accordingly, the corresponding blade models with a set of geometrical parameters are generated. Flow through a fan is simulated by solving the Reynolds-averaged Navier-Stokes equations. A multi-stage optimization scheme is employed to determine the family of optimum values for the parameters, leading to the pressure increase at the outlet of the fan. To validate the numerically obtained optimal design parameters, we fabricated the three types of fans using rapid prototyping and assessed the performance using a fan tester. Experimental results show that the design parameters at each stage satisfy the goal of optimization. The multi-stage optimization process turned out to be a useful tool in the development of a centrifugal fan.

Numerical Investigation of Liquid Flows in Parallel Columns for Use in the Al or Mg Die-Casting

  • Suh, Yong-Kweon;Li, Zi-Lu;Jeong, Jong-Hyun
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2005.10a
    • /
    • pp.229-234
    • /
    • 2005
  • Following the recent trend in the automotive manufacturing technologies, the product design subject to the die casting becomes more and more complex. The requirement of the die design becomes more demanding than ever before. In some cases the product's shape can have multiple slender manifolds. In such cases, design of the inlet and outlet parts of the die is very important in the whole manufacturing process. The main issues required for the qualified products are to attain gentle and uniform flow of the molten liquid within the passages of the die. To satisfy such issues, the inlet cylinder ('bed cylinder' in this paper) must be as large as possible and simultaneously the outlet opening at the end of each passage must be as small as possible. However these in turn obviously bring additional manufacturing costs caused by re-melting of the bed cylinder and increased power due to the small outlet-openings. The purpose of this paper is to develop effective simulation methods of calculation for fluid flows in multiple columns, which mimic the actual complex design, and to get some useful information which can give some contributions to the die-casting industry. We have used a commercial code CFX in the numerical simulation. The primary parameter involved is the size of the air-vent. We will show how the very small opening of the outlet, i.e. the air-vent, can be treated with the aid of the porous model provided in the code. To check the validity of the numerical results we have also conducted a simple experiment by using water.

  • PDF