• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.11a
• /
• pp.359-365
• /
• 2008

Turbopump test for a 30-ton-thrust liquid rocket engine was carried out using real-propellant. Liquid oxygen, kerosene, cold hydrogen gas were used for the oxidizer pump, the fuel pump, the turbine, respectively. The turbopump was run stably at the design and off-design conditions and the performance requirements were satisfied, which implies that the turbopump development at the engine subsystem level is successfully accomplished in the point of performance validation. This paper presents the results of a test where the turbopump was run for 75 seconds at three operating modes. In terms of performance characteristics of pumps and turbine, the results from turbopump assembly test using real-propellant showed a good agreement with those from the turbopump component tests using simulant working fluid.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.919-924
• /
• 2004

A CFA(Cooling Fan Assembly) is composed of a fan, motor and shroud, which is at the back of the automotive radiator. By forcing the wind to pass, the CFA controls the cooling performance of the radiator. The noise and vibration of the CFA may be primarily due to the resonance between the CFA and engine. The Interference among the fan, shroud and radiator by deformation is considered when the CFA is designed. In this paper, in order to analyze the structural vibration of the CFA for automobiles, a finite element model of the CFA is established by using a commercial FEM code. After the finite element modeling, the natural frequencies and the mode shapes are obtained from the FE analysis. The natural frequencies are obtained from the vibration test as well. Then, the results of the vibration test are compared with those of the FE analysis. The natural frequencies obtained by experiment have a great similarity to the results from FE model. We have confirmed the validity of the FE model and verify the structural safety for the resonance. The stress and displacements are obtained from FE analysis. We have confirmed the safety for the interference and failure.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.24 no.1
• /
• pp.130-134
• /
• 2015

The automobile industry is ubiquitous and involved in the handling of metal, machines, electricity, electron, and chemistry including the products of many types of processes. In the process of installing engines as a part of the car assembly line, the measurement and correction of the position of the stud bolts consumes a great deal of time. Additionally, defective parts must be manually removed. In the process of engine installation, the speed of the operation, related to the economics of vehicle assembly, is dependent upon measuring the precise position of the stud bolt, reducing the length of correction time, and increasing the working rate. This paper deals with securing the economic feasibility of the manufacturing process, increasing the safety by removing risk factors in the working area, and improving and equalizing the quality by developing an automatic system for the process involving a stud bolt.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.6
• /
• pp.91-100
• /
• 2016

Efficiency characteristics of centrifugal turbopumps for a liquid rocket engine were investigated. Predicting the performance of pumps for a turbopump assembly test, the variation on pump efficiency by working fluids was analyzed from pump component tests. Water and liquid nitrogen (LN2) were used for the component test, kerosene (Jet A-1) and liquid oxygen (LOX) were adapted for the turbopump assembly (TPU) test as working fluids. Overall performance of the pumps was investigated covering design/off-design operating points and the pump efficiency on the environment of real media (LOX/kerosene) could be modified from the pump component tests.

• The Journal of Korea Robotics Society
• /
• v.11 no.4
• /
• pp.270-276
• /
• 2016

This paper proposes a design methodology of self-reconfigurable kinematics and control engine for modular and reconfigurable robots. A modular manipulator has been proposed to meet the requirement of task adaptation in versatile needs for service and industrial robot area and the function of self-reconfiguration is required to extend the application of modular robots. Kinematic and dynamic contexts are extracted from the module and assembly information and related codes are automatically generated including controller. Thus a user can easily build and use a modular robot without professional knowledge. Simulation results are presented to verify the validity of the proposed method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.05a
• /
• pp.61-65
• /
• 2010

To research and develop a liquid rocket engine injector, it needs empirical studies about the hydrodynamic and spray characteristics such as pressure drop, mixing and atomization. In this study, the design and implementation of lab-scale cold-flow/hot fire test stand which can supply cryogenic propellant and be controlled by time-critical LabVIEW cyclogram logic has been done. In order to visualize the spray of a liquid-centered swirl coaxial injector in cryogenic condition, LN2-GN2 cold-flow test has been done, and combustor assembly and thrust bed for LOX-$GCH_4$ hot-fire test have been fabricated.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.17 no.6
• /
• pp.105-112
• /
• 2013

Turbopump is typically an assembly of rotors and casings, and there are a number of joints between them. Every joint should be leak-proof, so there is always a seal to accomplish the goal. Among various seals, metal seals are advantageous in that they are robust at high pressure, and at wide range of temperature. In this study, flange joints using conical seal made of stainless steel, solid flat metal seal made of copper and metal C seal made of Inconel 718 were structurally designed and analyzed, considering both initial tightening and operating conditions.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.198-200
• /
• 2017

An Auxiliary Power Unit (APU) is a small gas turbine engine that is mounted on an aircraft and serves to supply energy for ground and air starting of the main engine. APU also supplies emergency and auxiliary power for the aircraft. APU for aircraft is simple and compact in structure, but because it is mounted on manned aircraft, high reliability is required, so it must be proved its reliability through qualification procedure. The Korea Aerospace Research Institute and Hanwha Techwin successfully completed the design / analysis, fabrication, assembly, development test and certification test of APU for helicopter based on accumulated domestic R & D capability and experience from 2007 to 2012. In this paper, the development and certification process of auxiliary power unit for helicopter is summarized.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.4
• /
• pp.39-48
• /
• 2005

Finite element analyses have been performed for the purpose of obtaining the robust and reliable design of engine cylinder block. Fatigue under high cycle operating loads is a primary concern and is evaluated by a probabilistic method. The robust and reliable design by a probabilistic method can provide satisfactory design conditions for the performance of the system under the influence of noise factors. Therefore, the design by this method will be desensitized to the uncontrollable noise factors. The simple methodology evaluates the distortion of main bore is proposed for the purpose of maintaining a well-controlled clearance between the crankshaft and main bores. The proposed methodology has proven a capability of predicting the distortion of the main bore under assembly, thermal, and firing loads. The calculated results are correlated well with the experimental ones.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.243-247
• /
• 2004

The dynamometers which had made in a long time ago could not control the input/output quantity of water minutely and was sensitive to a noise since it was controlled by an analog control method. Therefore, a fully digital controlled system was urgently required to be robust against various noises. In this paper, the new system which can control the amount of circulated water in dynamometer was developed. This system is consisted of an industrial digital type controller and a servo motor. The industrial PLC was used as a main controller for the developed system, and the actuator and servo motor were used to control the inlet and outlet valve independently. The torque signal of load cell was fed back to the main controller to regulate the diesel engines load. Generally, an input/output valve position of the old dynamometer was fixed with a proper situation for an engine output test and the torque was changed according to the time interval. However, the torque value for the dynamometer could not be constantly kept because of the variation of the input water flow and fluid characteristic. Therefore, the automatic control of an inlet and outlet valve should be performed to keep the constant torque. So, the PID control method was applied to solve this problem. Also, the development of a web-based remote control system was described in this paper. This software will give us the convenience of operation, the more efficient operations, and the reduced operator workload for operation of the dynamometer. The application results of the system have been verified at actual diesel engine field.