• Title/Summary/Keyword: Side jet

Search Result 135, Processing Time 0.02 seconds

Numerical Investigation of Jet Interaction for Missile with Continuous Type Side Jet Thruster

  • Kang, Kyoung Tai;Lee, Eunseok;Lee, Soogab
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.16 no.2
    • /
    • pp.148-156
    • /
    • 2015
  • A continuous type side jet controller which has four nozzles with thrust control devices was considered. It is deployed to a missile for high maneuverability and fast controllability in the terminal guidance phase. However, it causes more complex aerodynamic jet interactions between the side jet and the supersonic free stream than does the conventional impulse type side jet with a small single thruster. In this paper, a numerical investigation of the jet interference effects for the missile equipped with a continuous type side jet thruster is presented. A three-dimensional flow field was simulated by using a commercial unstructured-based CFD solver. The numerical simulation method was validated through comparison with wind tunnel test results for the single jet. The method of defining jet direction for this type of side jet control to minimize simulation cases was also introduced. Flow fields investigation and jet interaction effects for various flow conditions, jet pressure ratios and defined jet direction conditions were performed. From the numerical simulation for the continuous type side jet, extensive aerodynamic interference data were obtained to construct an aerodynamic coefficients database for precise missile control.

Numerical Analysis on the Flow Characteristics of Side Jet Thruster (Side Jet 발생기의 유동특성에 관한 해석)

  • Hong S. K.;Sung W. J.
    • Journal of computational fluids engineering
    • /
    • v.6 no.3
    • /
    • pp.27-31
    • /
    • 2001
  • For rapid and abrupt control of a missile in supersonic flight, side jet on a missile body is found to be a useful device as evidenced by recent missile development at several nations. The magnitude of the side jet and the duration of it decide the level of control of such a missile system. In this paper, the aerodynamic characteristics of the side jet device itself are examined in terms of key parameters such as the side jet nozzle geometry, the chamber pressure and temperature. Specifically attention is paid to the effect of the chamber shape between the straight nozzle and the bent nozzle by 90 degrees on the nozzle flow properties. The thrust magnitudes are compared between the two shapes. Whether the way the nozzle is bent at the joint affects the nozzle performance is also investigated. Effects of the length and the divergence angle of the nozzle on the thrust are also quantified among three different side jet nozzles.

  • PDF

Computational Investigation of Similarity Law and Wind Tunnel Testing for Side Jet Influence on Supersonic Missile Aerodynamics (초음속 유도탄의 측추력기 작동시 풍동실험을 위한 CFD 해석 연구)

  • Hong S. K.;Sung W. J.
    • Proceedings of the KSME Conference
    • /
    • 2002.08a
    • /
    • pp.87-90
    • /
    • 2002
  • Computational study has been undertaken to investigate the aerodynamic influence of side jet on a supersonic missile and to find a similarity condition between the flight condition and the wind tunnel testing. Tasks were performed to validate the existing Raytheon test body with side jet, to simulate the flow inside the supersonic wind tunnel, and to compare the flow fields between the missile in free flight and that in the wind tunnel. Then sub-scale model of body-tail configuration was analyzed to estimate the influence of the side jet on the missile components. It Is found that the influence of side Jet is not as significant on the tail region as on the body surface and a simple algebraic formula for aerodynamic coefficients accounting for the side jet as a point force may be cautiously utilized in setting up control logic.

  • PDF

A Study on the Effects of Side Jets to the Longitudinal Aerodynamics of Subsonic Missile (측방 제트가 아음속 유도탄 종방향 공력특성에 미치는 영향 연구)

  • GO, Beom Yong;HUR, Ki Hoon
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.20 no.3
    • /
    • pp.393-404
    • /
    • 2017
  • Side jet effect on the aerodynamic characteristics of a missile was investigated using experimental and computational methods. A couple of side jets were injected toward outward downstream at mid point of missile body. Cold air jet was used in the wind tunnel test, and cold and hot jet were used in the computation. Wind tunnel test was carried out with jet and without jet, and calculation was performed for three cases ; no jet, cold air jet, and hot mixture gas jet. From the comparison of measured and calculated data for all cases, two points could be deduced. Firstly, side jet made static stability to be unstable by increasing body normal force near the side jet exit and by decreasing tail normal force. Secondly, hot mixture gas had more significant effect on the static stability of a missile-type body than cold air jet.

Numerical Analysis on the flow characteristics of L-type side jet thruster (L-type 측추력 발생장치의 유동특성 해석)

  • Lim, S.;Jeon, Y.J.;Cho, S.H.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.368-372
    • /
    • 2011
  • The aerodynamic characteristics of the L-type side jet thruster are examined by using computational fluid dynamics methods. The critical design points of L-type side jet thruster with bent nozzle by 90degrees are studied in terms of the relation between side jet nozzle geometry and thrust efficiency.

  • PDF

DSMC Calculation of the Hypersonic Free Stream and the Side Jet Flow Using Unstructured Meshes (비정렬 격자 직접모사법을 이용한 희박 유동과 측면 제트의 상호 작용에 관한 연구)

  • Kim M. G.;Kwon O. J.;Ahn C. S.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2004.03a
    • /
    • pp.126-131
    • /
    • 2004
  • The interaction between the hypersonic free stream and the side jet flow at high altitudes is investigated by direct simulation Monte Carlo(DSMC) method. Since there is a great difference in density between the free stream and the side jet flow, the weighting factor technique which could control the number of simulation particles, is applied to calculate these two flows simultaneously. Chemical reactions are not considered in the calculation. For validation, the corner flow passing between a pair of plates that are perpendicularly attached is solved. The side jet flow is then injected into this comer flow and solution is found for the merged flow. Results are compared with the experiments. For a more realistic rocket model, the flow past a blunted cone cylinder shape is solved. The leeward or windward jet injection is merged with this flow. The effect on the rocket surface is observed at various flow angles. The lambda effect and the wake structure are found like low attitudes. High interaction between the free stream and the side jet flow is observed when the side jet is injected in the windward direction.

  • PDF

Side Jet 발생기의 유동특성에 관한 연구

  • Hong Seung-Gyu;Seong Ung-Je
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2001.05a
    • /
    • pp.21-29
    • /
    • 2001
  • For rapid and abrupt control of a missile in supersonic flight, side jet on a missile body is found to be a useful devise as evidenced by recent missile development at several nations. The magnitude of the side jet and the duration of it decide the level of control of such a missile system. In this paper, the aerodynamic characteristics of the side jet devise itself are examined in terms of key parameters such as the side jet nozzle contour, the chamber pressure and temperature. Specifically attention is focused on the effect of the chamber shape between the straight nozzle and the bended nozzle by 90 degrees. The flow properties as well as the thrust level are compared between the two shapes. Particular attention is paid at the way the nozzle is bended at the joint. Effects of the length and the divergence angle of the nozzle on the thrust magnitude are also quantified among the three different side jet nozzles.

  • PDF

Computational Investigation of Similarity Law and Wind Tunnel Testing for Side Jet Influence on Supersonic Missile Aerodynamics (초음속 유도탄의 측추력기 작동시 풍동실험을 위한 CFD 해석 연구)

  • Hong S. K.;Sung W. J.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2002.05a
    • /
    • pp.41-46
    • /
    • 2002
  • Computational study has been undertaken to investigate the aerodynamic influence of side jet on a supersonic missile and to find a similarity condition between the flight condition and the wind tunnel testing. Tasks were peformed to validate the existing Raytheon test body with side jet, to simulate the flow inside the supersonic wind tunnel, and to compare the flow fields between the missile in free flight and that in the wind tunnel. Then sub-scale model of body-tail configuration was analyzed to estimate the influence of the side jet on the missile components. It is found that the influence of side jet is not as significant on the tail region as on the body surface and a simple algebraic formula for aerodynamic coefficients accounting for the side jet as a point force may be cautiously utilized in setting up control logic.

  • PDF

Analysis of the Interaction Between Side Jet and Supersonic Free Stream Using K-factor (상호 작용 계수를 이용한 측추력 제트와 초음속 자유류 상호 작용에 관한 연구)

  • Kim, Min-Gyu;Lee, Kwang-Seop
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.1
    • /
    • pp.101-110
    • /
    • 2012
  • The side jet effects between jet flow and free-stream on a missile body were investigated by experimentally and numerically for modeling aerodynamic coefficients in pitch plane. K-factors for normal force and pitching moment were introduced to estimate the side jet effects. The main parameters of the jet interaction phenomena were angle of attack, jet pressure ratio, Mach number and jet bank angle. The K-factors for normal force coefficient and pitching moment coefficients in pitch plane were analysed.