• Journal of the Korean Society of Propulsion Engineers
• /
• v.26 no.4
• /
• pp.64-71
• /
• 2022

For the development of an improved upper-stage engine, research on a staged combustion cycle liquid rocket engine is in progress. A cold flow test, ignition test, and combustion test plans were established and performed to develop reignition combustion technology. In order to solve the problem of purge gas flowing into the fuel line, which may cause cavitation in the turbo pump during reignition, the test results of each stage were analyzed. Based on the analysis results, the purge gas inflow problem was solved by reducing the overlapping time between the operation of the bubble removal valve and the opening of the purge valve and the engine fuel valve. Based on this, the reignition combustion test was successfully performed.

• Journal of Digital Contents Society
• /
• v.11 no.3
• /
• pp.385-392
• /
• 2010

At present, educational serious games which are designed for educational purpose including funny element have been developed in korea. This paper proposes a history educational game and describes how to make history educational game using OGRE engine. The OGRE engine is public, and widely used in many universities. Methods of the proposed game's development include development environment, desired plan, game scenario, game interface, method to cooperate with physics engine and so on. The proposed game is played in performing a mission that is based on historical event of our country in itself. And discrimination of the proposed game is to set a quest with actual historical events, in order to learn history beyond the simple fun in the existing history educational games. This paper should be helpful to discrimination of history educational serious game and developers to create history educational serious game with OGRE engine.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.25 no.4
• /
• pp.459-466
• /
• 2014

This paper deals with the method to classify the aircraft target by analyzing its JEM signal. We propose the method to classify the engine model by analyzing JEM spectrum using the harmonic frequency mask generated from the blade information of jet engine. The proposed method does not need the complicated logic algorithm to find the chopping frequency in each rotor stage and the pre-simulated engine spectrum DB used in the previous methods. In addition, we propose the method to estimate the precise spool rate and it reduces the error in estimating the number of blades or in calculating the harmonic frequency of frequency mask.

• International Journal of Automotive Technology
• /
• v.2 no.2
• /
• pp.39-45
• /
• 2001

Hydrogen is seen as one of the important energy vectors of the next century. Hydrogen as a renewable energy source, provides the potential for a sustainable development particularly in the transportation sector. Hydrogen driven vehicles reduce both local as well as global emissions. The laboratory of transporttechnology (University of Gent) converted a GM/Crusader V-8 engine for hydrogen use. Once the engine is optimised, it will be built in a low-floor midsize hydrogen city bus for public demonstration. For a complete control of the combustion process and to increase the resistance to backfire (explosion of the air-fuel mixture in the inlet manifold), a sequential timed multipoint injection of hydrogen and an electronic management system is chosen. The results as a function of the engine parameters (ignition timing. injection timing and duration, injection pressure) we given. Special focus is given to topics related to the use of hydrogen as a fuel: ignition characteristics (importance of electrode distance), quality of the lubricating oil (crankcase gases with high contents of hydrogen), oxygen sensors (very lean operating conditions), noise reduction (configuration and length of inlet pipes). The advantages and disadvantages of a power regulation only by the air to fuel ratio (as for diesel engines) against a throttle regulation (normal gasoline or gas regulation) are examined. Finally the goals of the development of the engine are reached: power output of 90 kW, torque of 300 Nm, extremely low emission levels and backfire-safe operation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.05a
• /
• pp.295-299
• /
• 2010

Recently, development and application of the condition monitoring and diagnostic system for improvement of durability and reliability and reduction of operating cost is generalized in the aircraft propulsion system. Especially, for reliable operation of the UAV which is flying in high altitude more than 40,000 ft for a long time an condition monitoring system to identify faults and degradations of its propulsion system should be needed. Therefore, this work proposes an on-line condition monitoring program using MATLAB/SIMULINK. In the development phase of the program, a engine signal generation module is used to simulate real engine measuring parameters instead of the real engine. The proposed on-line condition monitoring program was applied to a real turboprop engine to validate its application capability.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.03a
• /
• pp.84-88
• /
• 2008

The UAV propulsion system that will be operated for long time at more than 40,000ft altitude should have not only fuel flow minimization but also high reliability and durability. If this UAV propulsion system may have faults, it is not easy to recover the system from the abnormal, and hence an accurate diagnostic technology must be needed to keep the operational reliability. For this purpose, the development of the health monitoring system which can monitor remotely the engine condition should be required. In this study, a fuzzy trend monitoring method for detecting the engine faults including mechanical faults was proposed through analyzing performance trends of measurement data. The trend monitoring is an engine conditioning method which can find engine faults by monitoring important measuring parameters such as fuel flow, exhaust gas temperatures, rotational speeds, vibration and etc. Using engine condition database as an input to be generated by linear regression analysis of real engine instrument data, an application of the fuzzy logic in diagnostics estimated the cause of fault in each component. According to study results, it was confirmed that the proposed trend monitoring method can improve reliability and durability of the propulsion system for a long endurance UAV to be operated at medium altitude.

• Journal of the korean Society of Automotive Engineers
• /
• v.8 no.3
• /
• pp.16-27
• /
• 1986

In this study, low emission gasoline engine system is developed utilizing an EGR valve, 3 way catalytic converter and electronic fuel injection system. EGR was controlled by a needle valve and optimized at the engine conditions. Throttle body fuel injection system is used for fueling. When the engine was operated at constant speed by the electronic engine control system with the 3 way catalytic converter, th emissions were reduced by 50 to 90% in volume depending on he engine operating conditions.

• Tribology and Lubricants
• /
• v.17 no.6
• /
• pp.447-452
• /
• 2001

In development process of engine lubrication system, many failure cases are related with aeration problem. Therefore, it is very important to clarify the aeration in the engine oil circuit system. As of today, many factors have been introduced as the major cause in the engine oil aeration. However, still many test data related with those are required to clearly understand it. In this paper the aeration measurement system and calculation method are introduced. And also using this system we measured engine oil aeration for various cases. From these results some conclusions are reduced.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2000.11a
• /
• pp.171-176
• /
• 2000

In development process of engine lubrication system, many failure cases are related with aeration problem. Therefore, it is very important to clarify the aeration in the engine oil circuit system. As of today, many factors have been introduced as the major cause in the engine oil aeration. However, still many test data related with those are required to clearly understand it. In this paper the aeration measurement system and calculation method are introduced. And also using this system we measured engine oil aeration fur various cases. From these results some conclusions are reduced.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.5
• /
• pp.51-59
• /
• 2016

STS 321 stainless steel is generally used for a material of high-temperature and high-pressure system including liquid rocket engine. The constitutive equation for flow stress has been suggested using thermal stress component and athermal stress component based on Kocks dislocation barrier model to predict 321 stainless steel's deformation behavior at elevated temperature. The suggested model predicted well the material deformation behaviors of 321 stainless steel at the wide temperature range from room temperature to $500^{\circ}C$.