• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.99-105
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• 2005

To evaluate structural safety factor of the jet vane for the thrust deflection system under the dynamic pressure and very high temperature($2700^{\circ}C$) of the combustion gas flow, the high temperature tension tests of refractory metals and 3-D nonlinear numerical simulations are performed. Through the analysis of high temperature structural behavior for jet vane, the structural safety of jet vane is evaluated, and numerical results are compared with static pound tests of jet vanes. It has been found that most of structural and thermal loading is concentrated on the vane shaft which worked as safe under $1400^{\circ}C$. From the comparison of static ground tests and numerical results, the evaluation criterion using the vane load and shaft displacement is more useful to estimate the structural safety than using the equivalent stress.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.3
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• pp.18-24
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• 2005

To evaluate structural safety factor of the jet vane for the thrust deflection system under the dynamic pressure and very high temperature(2700$^{\circ}C$ ) of the combustion gas flow, the high temperature tension tests of refractory metals and 3-D nonlinear numerical simulations are performed. Through the analysis of high temperature structure behavior for jet vane, the structure safety of jet vane is evaluated, and numerical results are compared with static ground tests of jet vanes. It has been found that most of structural and thermal loading is concentrated on the vane shaft which worked as safe under 1400$^{\circ}C$. From the comparison of static ground tests and numerical results, the evaluation criterion using the vane load and shaft displacement is more useful to estimate the structural safety than using the equivalent stress.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.04a
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• pp.15-15
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• 2000

제트 베인에 의한 추력 방향 제어 장치는 롤 운동 제어를 가능하게 하고, 큰 선회 각도를 얻을 수 있는 장점이 있으나, 기계 장치가 비교적 복잡하고, 제트 베인의 열적, 구조적 문제를 해결하여야 한다. 복잡한 기계 장치는 유동 해석의 측면에서 고려해 볼 때 격자 형성을 어렵게 만들어 유동장 해석을 통한 성능예측을 어렵게 만든다. 구조물의 응력해석을 위하여 제트 베인 표면에서의 정압력과 더불어 마찰력도 고려하여야 하는데, 정확한 마찰력 계산을 위해서는 난류 모델링이 필수적이고, 그에 따라 벽면 근처에서 격자를 밀접시키는 것이 요구된다. 본 연구에서는 상용 유동해석 소프트웨어인 Fluent를 사용하여 제트 베인이 장착된 추력 방향 제어 장치의 3차원 난류 유동장 계산을 수행하였다. 피치, 요 운동의 경우와 롤 운동의 경우로 구분하여 계산하였으며, 최대 받음각을 $25^{\cire}$ 로 하여 제트 베인의 받음각에 따라 회전축에 작용하는 힘과 모멘트를 계산하였다. 본 연구의 결과는 향후 개발될 제트 베인이 장착된 추력 방향 제어 장치의 개념설계 단계에 필요한 기본자료로서 신뢰도를 높이는데 도움이 되리라 판단된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.283-291
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• 2011

A computational investigation has been carried out to study the heat transfer characteristics of jet vane assembly used for the thrust vector control(TVC) of a vertical launch motor. In this study, the coefficients of convective heat transfer on the jet vane are calculated using the solutions of thermal boundary-layer equation and several semi-empirical equations. The calculation of 3-dimensional temperature distribution for the jet vane assembly was performed using the softwares called PATRAN and ABAQUS. The accuracy of the present numerical method is verified by comparing with the measured and calculated temperatures within jet vane shaft. The temporal variation of jet vane temperatures for three deflection angles(0o, 12.5o, 25o) was discussed.

• The KSFM Journal of Fluid Machinery
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• v.15 no.6
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• pp.46-50
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• 2012

A high-speed centrifugal pump requires more attention to the control of its axial thrust due to the high discharge pressure than a conventional industrial pump. Vanes employed toward the rear cavity of the impeller can be an effective device to control the axial thrust of the pump. The vanes disturb circumferential flow of the cavity and it can modify the axial force acting on the impeller. In this paper, three types of vanes are installed in the high-speed centrifugal pump for liquid rocket engines and the thrust of the pump is measured with an additional thrust measurement unit. According to the results, shapes of cavity vanes have effects on the axial thrust of the pump. As the height of vanes increases, the outlet pressure of the rear floating ring seal decreases which results in a decrease of the thrust. On the other hand, head of the pump is almost same regardless of cavity vanes. Also, the pressure drop of the bypass pipeline increases when vanes are removed.

• Journal of the Korean Society of Propulsion Engineers
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• v.5 no.1
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• pp.26-33
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• 2001

Thrust vector control system is control device which is mounted exit of the nozzle to generate pitch, yaw and roll directional force by deflecting flow direction of the supersonic jet from the nozzle. By obtaining control force, jetvane which is exposed in jet flow is working thermal and aerodynamic load. Axial thrust loss and side thrust is affected by shock patterns and interactions between jetvanes according to jetvane geometry and turning angle. In this study, we designed 6 types of jetvane to evaluate pitch, yaw and roll characteristics of ietvane in supersonic flow, and perform the cold flow test in range of turning angles of jetvanes between $0^{\cire}$ and $25^{\cire}$ by $5^{\cire}$ respectively. Also, calculation is going side by side to analyse flow interaction. Results show that there is no interactions between jetvanes upto turning angle 20$^{\circ}$, chord and lead length ratio is very important parameter to aerodynamic performance and maximum thrust loss is appeard to 17% of axial thrust in roll directional control.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.2
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• pp.34-41
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• 2012

Thrust vector control system is a control device which is mounted on the exit of the nozzle to generate pitch, yaw and roll directional force by deflecting flow direction of the supersonic jet from the nozzle. Thermal and aerodynamic loads are acting on the surface of jet vane when it is exposed to the jet flow. Axial thrust loss and side thrust loss are affected by shock patterns and interactions between jet-vanes which varies with jet-vane geometry and turning angle. In this research, the performance estimation using the numerical simulation analysis of the nozzle is given and the investigation of the flow visualization and aerodynamic performance with the enforced power to the vane is taken.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.4
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• pp.397-404
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• 2012

In this research, a numerical study was carried out on the mixing and flow characteristics of a vane-type static mixer for the reduction of $NO_x$ in the SCR systems from the diesel exhaust environments. The mixer was located at a distance of 57 times the pipe diameter away from the inlet. The analyses were performed by changing various parameters such as vane angles, blockage ratio, and location of the vane. Flow characteristics through the mixer were characterized by the uniformity index, swirl number, and pressure drop. The results show that uniformity index, pressure coefficient and swirl number are substantially influenced by the vane angle, blockage ratio and position of the vane of the mixer. In particular, the swirl number was increased when the vane was located near the pipe wall, or the vane angle was increased or scale was extended.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.2
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• pp.7-13
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• 2015

In this study, we developed a gear-type vane damper which replaces the link type through a proper gear design by means of a finite element analysis. We analyzed the fluid flow according to the amount of angular displacement. torque and backlash problems were addressed in conjunction with the pinion as a structural improvement of the forced draft fan (FD FAN). Through an environmental test. Also, results nearly identical to those in the test could be drawn when using a numerical method. Finally, we compared the gear driving result with simulation results. objective of the present study is to identify a nonlinear flow rate control method for a gear-type vane damper and to propose a damper shape which offers linear flow rate control. This study is related to the development of a gear-type vane damper of the change-link type in a forced draft fan.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.1
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• pp.134-139
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• 2010

In this study, we developed the gear type vane damper replacing the link type through gear design using Finite Element Analysis(FEA). FEA about the pinion and the vane shaft in the boss of gear type damper for quality improvement was accomplished. We analyzed fluid flow according to angular displacement. Catched the problem of the torque and backlash bring to the pinion as structure improvement of the forced draft fan(FD FAN). Finally, we compared the gear driving result with simulation. It is the objective of the present study to identify a nonlinear flow rate control of gear type vane damper and to suggest a damper shape with a linear flow rate control. This study is related to the development of gear type vane damper change link type in forced draft fan.