• Title/Summary/Keyword: Multi Nozzle

Search Result 201, Processing Time 0.052 seconds

Multi-Body Dynamics Characteristics of Variable Nozzle (가변노즐의 다물체동력학적 특성)

  • Park, Dong-Chang;Lee, Sang-Youn;Yun, Su-Jin;Yoon, Hyun-Gull
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2010.11a
    • /
    • pp.711-712
    • /
    • 2010
  • In the present work, the dynamic characteristics of variable nozzles are described. Variable nozzles are used to enhance the effectiveness of aircraft engines at various altitudes. The dynamic characteristics of variable nozzle mechanism including flaps are analyzed by a multi-body dynamics analysis software, RecurDyn.

  • PDF

A Study on the Development of Two-phase Nozzle Suitable for Multi-purpose Spraying in Orchards (과수원 내 다목적 살포에 적합한 이류체 노즐 개발에 관한 연구)

  • Han, Kwang Ho;Kang, Tae Gyoung;Lee, Dong In;Lee, Chul-Hee
    • Journal of Drive and Control
    • /
    • v.17 no.4
    • /
    • pp.1-7
    • /
    • 2020
  • In orchard or crop-growing environments, pesticides are sprayed using various nozzles to prevent pests and improve productivity. Nozzles currently in use are restricted for use in multi-purpose environments, thus, it is necessary to develop new nozzles. In this study, new two-phase nozzles are proposed to improve the performance of the nozzle (flow rate, spray angle, spray particle size). The performance of the two-phase nozzles are predicted through the CFD analysis and the performance of the nozzles is compared with the experiment. The experimental results showed that the proposed two-phase nozzles are available at relatively low operating pressure condition and are capable of extensive spray particle size control. Thus, the proposed nozzles are expected to be available in various orchard environments.

Numerical Study to Develop Low-NOx Multi-nozzle Burner in Rotary Kiln (로터리 킬른용 Low-NOx 다공노즐버너 개발을 위한 수치해석적 연구)

  • Ahn, Seok-Gi;Kim, Jin-Ho;Hwang, Min-Young;Kim, Gyu-Bo;Jeon, Chung-Hwan
    • Journal of Energy Engineering
    • /
    • v.23 no.4
    • /
    • pp.130-140
    • /
    • 2014
  • Rotary kiln burner has been developed continuously to improve process efficiency and exhaust emission. In this study, the characteristics of the flame and exhaust emission were numerically analyzed according to the diameter of primary air nozzle, equivalent ratio of burner, and equivalent ratio at center and side nozzle for development of multi-nozzle burner in the COG(Coke Oven Gas) rotary kiln for sintering iron ore. The results indicated that the flame length and $NO_x$ emission increase, as the diameter of primary air nozzle and equivalent ratio of burner increase. And according to the change of equivalent ratio at the center and the side of the nozzle, the flame length and average temperature in the kiln show very little change but the $NO_x$ emission shows obvious difference. In conclusion, the best design conditions which have satisfying flame length, average temperature and $NO_x$ emission are as follows: $D_2/D_1$ is 1.33, equivalent ratio of burner is 1.25 and center nozzle conditions are Rich.

Analysis of Unsteady Cavitating Flows in Fuel Injection Nozzle of Piezo-driven Injector by Eulerian-Lagrangian Multi-phase Method (Eulerian-Lagrangian 다상 유동해석법에 의한 피에조 인젝터의 노즐 내부 비정상 캐비테이션 유동해석)

  • Lee, Jin-Wook;Min, Kyung-Duk;Kang, Kern-Yong;Gavaises, M.;Arcoumanis, C.
    • Journal of ILASS-Korea
    • /
    • v.9 no.4
    • /
    • pp.38-45
    • /
    • 2004
  • This study describes the analysis results of unsteady cavitating flows behavior inside nozzle of the prototype piezo-driven injector. This piezo-driven injector has been recognised as one of the next generation diesel injector due to a higher driven efficiency than the conventional solenoid-driven injector. The three dimensional geometry model along the central cross-section regarding of one injection hole has been used to simulate the cavitating flows for injection time by at fully transient simulation with cavitation model. The cavitation model incorporates many of the fundamental physical processes assumed to take place in cavitating flows. The simulations performed were both fully transient and 'pseudo' steady state, even if under steady state boundary conditions. We could analyze the effect the pressure drop to the sudden acceleration of fuel, which is due to the fastest response of needle, on the degree of cavitation existed in piezo-driven injector nozzle

  • PDF

A STUDY ON FLOW MIXING IMPROVEMENT OF SELECTIVE CATALYTIC REDUCTION USING GASEOUS REDUCTANT (기상 환원제를 사용하는 선택적 환원촉매에서 유동혼합 개선에 관한 연구)

  • Ko, S.C.;Lee, B.H.;Cho, S.H.;Lee, S.H.;Hong, S.T.;Lee, D.Y.
    • Journal of computational fluids engineering
    • /
    • v.15 no.1
    • /
    • pp.56-63
    • /
    • 2010
  • Since emission regulations for vehicles have become more stringent, SCR technology has drawn a strong attention in order to reduce NOx emissions. Optimal design of a reductant injection nozzle and a multi-hole plate located between the cone and catalyst is critical in that the uniform distribution of reductant is necessary to maximize the NOx conversion efficiency and minimize the slip of reductant in SCR. In this work, an LPG fuel(C3H8 in vapor state) was used as a reductant for LPG vehicles. A Realizable k-$\varepsilon$ model is used for turbulence, and SCR body is defined as porous media with inertia and viscous resistances measured in this work. Effect of the number of nozzle holes on the flow mixing index was analyzed, which revealed that a four hole nozzle shows the best performance in terms of uniformity of flow. An installment of a multi-hole plate at the entrance of catalyst was evaluated with flow mixing index, uniformity of flow, and pressure drop. A multi-hole plate with gradual hole diameter change in three steps showed the best uniformity of flow within the conditions suggested in this work.

A Study on Relation of Needle-Nozzle Flow of Piezo-driven Injector by using Eulerian-Lagrangian Multi-phase Method (Eulerian-Lagrangian 다상 유동해석법에 의한 피에조인젝터의 니들-노즐유동 상관성 연구)

  • Lee, Jin-Wook;Min, Kyoung-Doug
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.18 no.5
    • /
    • pp.108-114
    • /
    • 2010
  • The injection nozzle of an electro-hydraulic injector is being opened and closed by movement of a injector's needle which is balanced by pressure at the nozzle seat and at the needle control chamber, at the opposite end of the needle. In this study, the effects of needle movement in a piezo-driven injector on unsteady cavitating flows behavior inside nozzle were investigated by cavitation numerical model based on the Eulerian-Lagrangian approach. Aimed at simulating the 3-D two-phase flow behavior, the three dimensional geometry model along the central cross-section regarding of one injection hole with real design data of a piezo-driven diesel injector has been used to simulate the cavitating flows for injection time by at fully transient simulation with cavitation model. The cavitation model incorporates many of the fundamental physical processes assumed to take place in cavitating flows. The simulations performed were both fully transient and 'pseudo' steady state, even if under steady state boundary conditions. As this research results, we found that it could analyze the effect the pressure drop to the sudden acceleration of fuel, which is due to the fastest response of needle, on the degree of cavitation existed in piezo-driven injector nozzle.

Measurement and Evaluation of Cross-talk Effects in Multi-nozzle Inkjet Head (다중 노즐 잉크젯 헤드의 상호 간섭 측정 및 평가)

  • Kwon, Kye-Si;Kim, Jin-Won
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.28 no.1
    • /
    • pp.73-79
    • /
    • 2011
  • Inkjet printhead may have a lot of nozzles to increase productivity as a manufacturing tool. So, the uniformity of jetting performance among a lot of nozzles has been one of the key issues in inkjet technology In this study, we investigated the cross-talk effect which should be reduced for uniform jetting performance among a lot of nozzles. Due to the cross-talk, the jetting performance of a nozzle can be affected when neighboring nozzles are firing. For experimental study, we used commercial inkjet head SE-128 from Dimatix. To understand the cross-talk effect of SE-128 head, we measured the change in jetting speed of a nozzle when neighboring nozzles are jetting. The measured jetting speed was compared to the case of one nozzle jetting. Also, we used laser vibrometer to measure change in pressure wave due to cross-talk. As a result of the cross-talk, the jetting speed can become faster or sometimes slower depending on firing nozzle location. If the all nozzle are jetting, the jetting speed of a nozzle became slower because the pressure wave for jetting is reduced.

A Study on the Characteristics of Jet Pump Having Exteriorly Connected Multi-nozzles (다중 노즐을 이용한 중앙 분사형 제트 펌프의 성능에 관한 연구)

  • Kim, M.K.;Kwon, O.B.;Kim, H.G.;Lee, C.G.
    • Journal of Power System Engineering
    • /
    • v.4 no.1
    • /
    • pp.33-38
    • /
    • 2000
  • The characteristics of center-driver jet pump which have multi-nozzle were studied in this research. Jet nozzles are connected outside of the bend rather than inserted in the bend in order to transport solid materials or fish without any harm. Jet pumps having one nozzle, two nozzles, four nozzles, and sixteen nozzles were tested in this study. The efficiencies and performances of jet pumps were studied for several nozzles shape, for three different mixing chamber shapes, for two suction area shapes. All the efficiency curves for these cases are presented in this paper.

  • PDF

A Study on the Development of an Automatic Multi-Nozzle Injection Molding Machine (Multi-Nozzle Injection Molding Automatic Machine 개발에 관한 연구)

  • Lee, Jong-Hyung;Kim, Jung-Hwan;Yi, Chang-Heon;Kim, Yun-Gon;Lim, Chun-Kyoo;Lee, Chun-Kon;Kwon, Yung-Shin
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.10 no.2
    • /
    • pp.123-128
    • /
    • 2007
  • The demand for the precision rubber products has been rapidly increasing with the recent growth of industries. And the requirement for the productivity and the quality calls out for the injection molding machines with the precision machining ability as well as the high productivity. Especially modern automobile industry is in urgent need of developing injection molding machines for the high quality rubber products with high productivity. And the inability of the domestic companies to meet the standards causes importing foreign machines and as a result spending good amount of dollars. It is extremely important to develop competitive machines and strengthen the infrastructure of the related industries. In this paper the functions and the structure of a automatic multi-nozzle injection molding machine has been studied to set up a proper test system for the precision rate and the reliability of the machines, which can help build the machines to meet the request of the industry.

  • PDF