수소 압축기용 릴리프 밸브 모델링 및 성능해석에 관한 연구

박상법,김규보,윤소남,권병수 한국수소및신에너지학회 2009 한국수소 및 신에너지학회논문집 Vol.20 No.3

This paper presents a static and dynamic characteristics of the relief valve which is a kind of direct operated pressure control valve for hydrogen compressor. The valve is consisted of a main poppet, a spring, an adjuster and a valve body. The purpose of this study is development of the simulation model for relief valve by using commercial AMESIMⓇ tool. Poppet with sharp edge seat type and ball poppet with sharp edge seat type compare for P-Q characteristic. The dynamic simulation results are presented the operating pressure characteristics of relief valve. High pressure power unit of which maximum pressure control range is 100MPa was manufactured, and the pressure control valve was experimented using the above-mentioned power unit. The new model of pressure control valve from this results was suggested. It was confirmed that the suggested valve has a good control performance from experimental setup.

유한요소법을 이용한 서지 릴리프 밸브의 디스크 시일 최적설계

공재현(Kong J. H.),이성철(Lee S. C.),예상돈(Ye S. D.),허관도(Hur K. D.) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

The mega-projects that are Ocean plant, seawater desalination, nuclear power generation, etc are recently gaining the world's interest. The projects are certain to need surge relief valve that is one of the elements for the safety of the plant system. The surge relief valve is a safety device to protect surge pressure such as water hammer. Water Hammer is caused by sudden changes in flow. In recent years Pumping Systems have become large scale and surge relief valve have become large scale. disc seal that is important parts of surge relief valve have effect on quality. Disc seal with disc and disc seat are served as sealing function in the surge relief valve. The sealing force on the disc seal is analyzed by the FEM and design values are optimized by using the Taguchi method.

선박엔진용 Crankcase Relief Valve의 구조 해석 및 역설계

조호준(Ho-Jun Cho),이영주(Young-Ju Lee),박수건(Su-Kun Park),윤한기(Han-Ki Yoon) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

The relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. But we are depending on technology of a foreign country to the present time because we don't have our own technology. Therefore, we have developed a new relief valve which is a safety device for the domestic crankcase relief valve.

한국형발사체 산화제 탱크용 벤트/릴리프밸브 개발

고현석,장제선,이무근,한상엽 한국항공우주학회 2012 한국항공우주학회 학술발표회 논문집 Vol.2012 No.11

한국형발사체의 추진제 공급 시스템에 사용되는 산화제 탱크용 벤트/릴리프밸브의 개발을 진행하고 있다. 벤트/릴리프밸브는 산화제 충전 시 탱크 내부에서 기화되는 가스를 배출하고, 충전 후에는 과압이 걸리지 않도록 보호하는 역할을 한다. 충전 중 탱크 배기는 벤트밸브에서 담당하며 탱크의 보호는 릴리프밸브와 벤트밸브의 연계 작동을 통하여 이루어진다. 수치해석을 통하여 공압 성능 및 동특성이 밸브요구조건을 만족하는 것을 확인하였다. 시제품 모델 개발을 통해 제작 공정을 수립하였고 벤트/릴리프밸브의 성능을 평가하기 위한 시험을 수행하고 있다. 납품을 위한 시제품 개발은 2014년까지 완료할 예정이다. A vent relief valve for oxidizer tank has been developed for liquid propellant feed system of the KSLV-Ⅱ. The vent relief valve ensures oxidizer tank ventilation during filling and its protection from overpressure after filling. Tank ventilation during filling is ensured by vent valve and tank protection is ensured by combined operation of relief valve and vent valve. Numerical analysis predicted that pneumatic behavior and dynamic characteristics met the valve requirements. We prepared the manufacturing process during the prototype model phase, and have been conducting the tests to evaluate the performance of the vent relief valve. Finally, we plan to complete the development model for delivery by 2014.

안전릴리프밸브의 블로우 다운 예측 및 유체-구조 연성해석

최지원(Ji-Won Choi),장시환(Si-Hwan Jang),이권희(Kwon-Hee Lee) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.12

안전릴리프밸브는 배관라인 혹은 탱크의 과도한 압력을 완화하고 사용 적정압력 수준으로 유지해주는 장치이다. 안전릴리프밸브는 스프링 보닛에 통풍구가 대기 쪽으로 혹은 배출구 쪽으로 뚫려 있는지에 따라 배압의 변화에 직접적으로 영향을 받게 된다. 배압은 축적 배압(Built-up back pressure)과 부과 배압(superimposed back pressure)으로 나뉘게 되며 사용조건에 따라 배압의 특성이 달라진다. 본 연구에서 사용되는 안전밸브는 Conventional Safety Relief Valve로써, 배압의 특성을 가정하였다. 또한 개방력과 스프링력 사이의 힘의 평형 방정식을 세워 이론적 접근방법으로 초기 스프링 변위를 구하였다. 디스크가 받는 반력 즉 개방력과 스프링력을 비교하여 블로우 다운을 예측하였다. 블로우 다운은 설정 압력과 디스크 재닫힘 압력 간의 차이다. 본 연구는 ASME 규격 코드에 따라서 블로우 다운 시험 전에 전산 유동해석프로그램 CFX17.1을 이용하여 수치적으로 예측하였음을 밝힌다. 또한 유체-구조 연성해석(fluid-structure interaction analysis)을 통해 안전밸브 트림부의 안전성을 검토하였다. 향후, 시험과 전산수치해석 값을 서로 비교하여 블로우 다운 이론적 접근방법과 유동해석방법을 제안하고자 한다. A safety relief valve is a device that relieves excessive pressure in piping lines or tanks and maintains pressure at the appropriate pressure level for use. The (pressure in the) safety valve is directly influenced by the change in the back pressure, depending on whether the vents in the spring bonnet are vented to the atmosphere or to the outlet. The back pressure is divided into the built-up back pressure and the superimposed back pressure, and the back pressure characteristics vary according to the usage conditions. The safety valve used in this study is a Conventional Safety Relief Valve. The blowdown of the safety valve is predicted by establishing the equilibrium equation between the opening force and spring force considering the back pressure characteristics. Its reliability is secured by using CFX17.1. In addition, the safety of the safety valve trim was examined through fluid-structure interaction analysis.

LNG 연료추진 선박용 크랭크실 릴리프 밸브 스프링의 설계 및 평가

이효렬(Hyo Ryeol Lee),안중환(Jung Hwan Ahn),안병훈(Byoung Hoon Ahn),김화영(Hwa Young Kim) 한국생산제조학회 2015 한국생산제조학회지 Vol.24 No.3

Growing concerns regarding air pollution have recently increased the demand for liquefied natural gas (LNG) fueled ships. LNG-fueled ships are equipped with an explosion relief valve in the crankcase to relieve excessive pressure and stop flames from emitting from the crankcase. In this study, a finite element analysis was conducted to evaluate the crankcase relief valve disk spring design using an ANSYS Workbench, v.15. The setting pressure, leak and explosion test performed by european standard EN14797 to evaluate function and mechanical integrity of crankcase relief valve. The tests results indicate that the pressure of the crankcase relief valve is 3.05 bar, with no air leakage at 2.97 bar. Finally, the mechanical integrity of the crankcase relief valve was confirmed through an explosion test in which the valve plate assembly, flame arrester, and other parts were safe from fracturing.

연료 벤트/릴리프 밸브의 설계 분석

장제선(Jang, JeSun),길경섭(Kil, GyoungSub),한상엽(Han, SangYeop),박종호 한국항공우주연구원 2012 항공우주기술 Vol.11 No.2

우주발사체의 액체추진공급시스템에서 사용되는 연료 벤트/릴리프밸브는 안전밸브의 조합체로 지상에서 연료를 주입할 때와 비행 중에 추진제 탱크의 과압을 해소하는 역할을 한다. 벤트/릴리프밸브는 구동가스 공급에 의해 벤트밸브를 작동시키는 벤트모드와 설정된 압력을 유지하기 위해 자동으로 밸브를 개폐하는 릴리프모드로 작동한다. 본 논문에서는 해외발사체에 사용된(Saturn) 벤트/릴리프밸브 샘플을 이용하여 한국형발사체의 규격에 적용한 밸브 설계를 검토하였다. 또한 설계 검증 및 기본적인 작동 특성을 분석하기 위해 AMESim 상용코드를 이용하여 해석 모델을 구성하였다. 밸브 모델을 이용해서 동특성 해석을 수행하여 설계 변수에 대해 밸브 개폐 작동시간, 작동성능, 개폐압력을 예상하였다. 이를 통해 연료 벤트/릴리프밸브 설계변수에 따른 작동성을 파악하여 시제품 제작 전 의상세설계 및 설계 경계조건을 제시하였다. A vent-relief valve performs as a safety-valve assembly for liquid propellant feeding system of space launch vehicle, which relives pressurant propellant tanks during the filling and the flight. At vent mode, valve is opened and closed by driving pneumatic pressure, and at relief mode, valve is automatically operated to set relief pressure. In this study, we have analyzed a basic layout of vent-relief valve which is designed using foreign LVs(Saturn) to satisfy requirements of Korean Space Launch Vehicle. The simulation model of vent-relief valve is designed by using the AMESim code to verify design parameters and evaluate pneumatic behaviors of valve. In this study, we performed dynamic characteristic simulations on design parameters. And we could predict opening/closing time and pressures, operating performances on design parameters. Using this results, we could suggest detail design and boundary conditions of design.

모바일 유압장치에서 부하의 유지와 내림 특성 비교

조미현(Mi Hyeon Jo),허준영(Jun Young Huh) 유공압건설기계학회 2018 드라이브·컨트롤 Vol.15 No.4

Mobile hydraulics require higher energy efficiency, and a simpler as well as robust design, than general industrial hydraulics. The 6/3-way directional control valve is widely used as a mobile hydraulic control valve. However, since the 6/3-way directional control valve is a spool type valve, it is difficult to maintain the load. A counterbalance valve is typically used, to maintain the load, and lift down. However, in an industrial field using a mobile hydraulics device, a pilot controlled check valve may be used to implement holding and lifting operation of the self-weight load, and a relief valve may be used simply to exert back pressure. But no comparative analysis of advantages and disadvantages of each method was revealed. In this study, various methods of holding and unloading load with self-weight in mobile hydraulics are investigated, and compared through simulation using AMESim software. This is experimentally verified by using Festo"s mobile hydraulic test rig TP800.

Pressure-relief valve를 적용한 착륙장치 완충장치 설계

김태욱(Tae-Uk Kim),신정우(JeongWoo Shin),황인희(In Hee Hwang) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11

The most landing gear use oleo-pneumatic shock strut to absorb the impact energy during touchdown. The shock strut is composed of the oil damper and the gas spring, especially the oil damper provides resistance force which is proportional to the square of landing speed. In case of high landing speed, the abnormal peak load can be occurred and transferred to the airframe structure. To prevent this, the pressure-relief valve is used to limit the damping force under the specific level. In this paper, it is presented the design process to find optimal damping and analysis results using pressure-relief valve.

LNG / LNG-FPSO 선박용 컨벤셔널 및 파일럿 타입 밸브의 구조성능평가

황동욱(Dong Wook Hwang),김성진(Sung Jin Kim),배준호(Jun Ho Bae),정성윤(Sung Yuen Jung),김철(Chul Kim) Korean Society for Precision Engineering 2012 한국정밀공학회지 Vol.29 No.12

Safety valve used in LNG/LNG-FPSO ships is a high value valve, and it plays an important role in maintaining a fixed level of pressure by emitting LNG gas out of pipes in LNG piping system under the cryogenic and high-pressure condition when the pressure of the system connected with the LNG storage tank and pipes reaches over the set pressure. The structural stability is required for the inner pressure and thermal load because of the cryogenic and high-pressure condition, and a reliability of the safety valve is necessary for impact and deformation by opening the valve. But, the safety valve, which plays a key role for a safety of the transport and storage system, is depended on imports for over 90%, and in domestic production, the design of the valve is performed on the basis of experiences of the works without quantitative analysis for the inner operation characteristics and structural stability of the valve. In this study, impact velocity is calculated by theoretical analysis for obtaining the structural stability of the guide according to the impact load by opening the valve. The shape of the guide and the diaphragm for satisfying the structural stability are suggested and verified by using a thermal-structural analysis.