LM-5 booster separation test achieved success in Tianjin new generation launch vehicle industrial base on May 31. The test mainly demonstrated whether the boosters can separate from the rocket safely during the flight...LM-5 booster separation test achieved success in Tianjin new generation launch vehicle industrial base on May 31. The test mainly demonstrated whether the boosters can separate from the rocket safely during the flight, the correctness of the design of separation system and its reliability. Many important parameters including展开更多
The LM-5B launch vehicle has successfully completed four missions.Eight high-pressure staged combustion LOX/kerosene engines(YF-100)are equipped in the four boosters of the LM-5B,two in each booster.The YF-100 engine ...The LM-5B launch vehicle has successfully completed four missions.Eight high-pressure staged combustion LOX/kerosene engines(YF-100)are equipped in the four boosters of the LM-5B,two in each booster.The YF-100 engine adopts various cooling techniques to ensure cooling,including a metal thermal barrier coating,multiple liquid film cooling slots,spiral milled regenerative cooling channels with high aspect ratio,a non-weld forming thrust chamber and an optimal cooling flow path design.In addition,the 480-ton LOX/kerosene engine for China’s future heavy-lift launch vehicle LM-9 will be larger in size,which makes it more difficult to be developed and will have more strict requirements in the cooling process.The main differences between the LM-5B and LM-5 are briefly described in this paper and the development process and working characteristics of YF-100 engines are introduced.The advantages and disadvantages of main cooling methods used in the thrust chambers of high-thrust liquid propellant engines are also described.Finally,the future challenges and countermeasures in cooling technology for China’s high-thrust LOX/kerosene engines and future reusable rocket engines are also presented.展开更多
The LM-5B carrier rocket’s first stage is equipped with eight 120 t.thrust high-pressure staged combustion LOX/kerosene engines(YF-100).The YF-100 engine features a throttle valve in the main fuel path,which allows t...The LM-5B carrier rocket’s first stage is equipped with eight 120 t.thrust high-pressure staged combustion LOX/kerosene engines(YF-100).The YF-100 engine features a throttle valve in the main fuel path,which allows the adjustment of the throttle area,thereby controlling the engine’s mixture ratio.Engine parameters for the throttle valve were determined based on design conditions(mixture ratio of 2.6),and the engine was then tested for ignition.After testing,if the mixture ratio was found not to meet the overall requirements of the rocket,the throttle area could be adjusted prior to subsequent ignition or installation in the whole system,enabling a secondary adjustment of the mixture ratio.This paper outlines the methodology for static parameter calculations of the engine and the analysis of internal and external interference factors,and presents a scheme for the secondary adjustment of the engine’s mixture ratio and examines the precision of this secondary adjustment.The mixture ratio adjustment technology can notably reduce the dispersion range of mixture ratios for YF-100 engines.Moreover,the influence of mixture ratio adjustment on engine performance parameters was obtained.The approach of mixture ratio adjustment proposed in this paper lays the technical foundation for the precise adjustment of mixture ratio for future heavy-lift rocket engines.展开更多
The LM-5B carrier rocket is a new-generation large-scale launch vehicle developed for space station launch missions.Its separation system includes fairing separation,space station module-rocket separation,and booster ...The LM-5B carrier rocket is a new-generation large-scale launch vehicle developed for space station launch missions.Its separation system includes fairing separation,space station module-rocket separation,and booster separation.The separation systems play an important role in the design of launch vehicles,and any failure during the separation process would affect the final completion of rocket flight mission.This paper presents the reliability design and analysis for the LM-5B carrier rocket separation system.The LM-5B carrier rocket separation system was developed on the basis of the LM-5 carrier rocket separation system,inheriting its booster separation system and fairing separation system scheme,which maximizes the reliability of the separation system.The reliability of the LM-5B fairing separation system,booster separation system and space station module-rocket separation system can meet the requirements for launch missions.The demonstration results prove that redundant design of the separation systems was the most effective technical means to improve reliability.展开更多
The LM-5B launch vehicle is a new-generation large launch vehicle specially developed for the construction of China’s space station under its manned space program,and it has the largest launching capacity to low Eart...The LM-5B launch vehicle is a new-generation large launch vehicle specially developed for the construction of China’s space station under its manned space program,and it has the largest launching capacity to low Earth orbit in China.The LM-5B booster is the largest booster ever built in China,which can produce 90%of the total thrust at liftoff,which laid a solid foundation for the successful development of the LM-5B launch vehicle.The booster team has overcome many technical challenges and gained rich experience in developing large cryogenic launch vehicles.展开更多
Structural vibration modes of large clustered liquid launch vehicles are important criteria for attitude stability design,POGO stability design and structural dynamic load calculation.As the first large one-stage-to-o...Structural vibration modes of large clustered liquid launch vehicles are important criteria for attitude stability design,POGO stability design and structural dynamic load calculation.As the first large one-stage-to-orbit clustered liquid launch vehicle of China,LM-5B has unique structural modal properties which are different from other launch vehicles at home and abroad because of its special structural scheme.Hence,it was necessary to study the structural modal properties for LM-5B.In this paper,ground modal tests for the whole vehicle were conducted to verify and modify the finite-element model of LM-5B,then the structural modal properties were obtained via simulation during flight time,providing significant input for the development of the vehicle.展开更多
Two new steroidal glycosides named Lm-4 （1） and Lm-5 （2） were isolated from the tubers of Liriope muscari. Their structures were elucidated by 1D and 2D NMR, ESI/MALDIMS techniques, and chemical methods.
In the past 2 years, China's new generation launch vehicles, such as the LM-6, LM-7, LM-5 and LM-11 launch vehicles, successfully made the maiden flights, which marked Chinese Long March series launch vehicles hav...In the past 2 years, China's new generation launch vehicles, such as the LM-6, LM-7, LM-5 and LM-11 launch vehicles, successfully made the maiden flights, which marked Chinese Long March series launch vehicles having many achievements such as the diameter of launch vehicles increased from 3.35 m to 5 m and the toxic propellants replaced with non-toxic and pollution-free propellants. This paper will introduce the features and new technology of LM-7, LM-5 and LM-11 launch vehicles, which are China's new typical generation Launch vehicles.展开更多
文摘LM-5 booster separation test achieved success in Tianjin new generation launch vehicle industrial base on May 31. The test mainly demonstrated whether the boosters can separate from the rocket safely during the flight, the correctness of the design of separation system and its reliability. Many important parameters including
文摘The LM-5B launch vehicle has successfully completed four missions.Eight high-pressure staged combustion LOX/kerosene engines(YF-100)are equipped in the four boosters of the LM-5B,two in each booster.The YF-100 engine adopts various cooling techniques to ensure cooling,including a metal thermal barrier coating,multiple liquid film cooling slots,spiral milled regenerative cooling channels with high aspect ratio,a non-weld forming thrust chamber and an optimal cooling flow path design.In addition,the 480-ton LOX/kerosene engine for China’s future heavy-lift launch vehicle LM-9 will be larger in size,which makes it more difficult to be developed and will have more strict requirements in the cooling process.The main differences between the LM-5B and LM-5 are briefly described in this paper and the development process and working characteristics of YF-100 engines are introduced.The advantages and disadvantages of main cooling methods used in the thrust chambers of high-thrust liquid propellant engines are also described.Finally,the future challenges and countermeasures in cooling technology for China’s high-thrust LOX/kerosene engines and future reusable rocket engines are also presented.
文摘The LM-5B carrier rocket’s first stage is equipped with eight 120 t.thrust high-pressure staged combustion LOX/kerosene engines(YF-100).The YF-100 engine features a throttle valve in the main fuel path,which allows the adjustment of the throttle area,thereby controlling the engine’s mixture ratio.Engine parameters for the throttle valve were determined based on design conditions(mixture ratio of 2.6),and the engine was then tested for ignition.After testing,if the mixture ratio was found not to meet the overall requirements of the rocket,the throttle area could be adjusted prior to subsequent ignition or installation in the whole system,enabling a secondary adjustment of the mixture ratio.This paper outlines the methodology for static parameter calculations of the engine and the analysis of internal and external interference factors,and presents a scheme for the secondary adjustment of the engine’s mixture ratio and examines the precision of this secondary adjustment.The mixture ratio adjustment technology can notably reduce the dispersion range of mixture ratios for YF-100 engines.Moreover,the influence of mixture ratio adjustment on engine performance parameters was obtained.The approach of mixture ratio adjustment proposed in this paper lays the technical foundation for the precise adjustment of mixture ratio for future heavy-lift rocket engines.
文摘The LM-5B carrier rocket is a new-generation large-scale launch vehicle developed for space station launch missions.Its separation system includes fairing separation,space station module-rocket separation,and booster separation.The separation systems play an important role in the design of launch vehicles,and any failure during the separation process would affect the final completion of rocket flight mission.This paper presents the reliability design and analysis for the LM-5B carrier rocket separation system.The LM-5B carrier rocket separation system was developed on the basis of the LM-5 carrier rocket separation system,inheriting its booster separation system and fairing separation system scheme,which maximizes the reliability of the separation system.The reliability of the LM-5B fairing separation system,booster separation system and space station module-rocket separation system can meet the requirements for launch missions.The demonstration results prove that redundant design of the separation systems was the most effective technical means to improve reliability.
文摘The LM-5B launch vehicle is a new-generation large launch vehicle specially developed for the construction of China’s space station under its manned space program,and it has the largest launching capacity to low Earth orbit in China.The LM-5B booster is the largest booster ever built in China,which can produce 90%of the total thrust at liftoff,which laid a solid foundation for the successful development of the LM-5B launch vehicle.The booster team has overcome many technical challenges and gained rich experience in developing large cryogenic launch vehicles.
文摘Structural vibration modes of large clustered liquid launch vehicles are important criteria for attitude stability design,POGO stability design and structural dynamic load calculation.As the first large one-stage-to-orbit clustered liquid launch vehicle of China,LM-5B has unique structural modal properties which are different from other launch vehicles at home and abroad because of its special structural scheme.Hence,it was necessary to study the structural modal properties for LM-5B.In this paper,ground modal tests for the whole vehicle were conducted to verify and modify the finite-element model of LM-5B,then the structural modal properties were obtained via simulation during flight time,providing significant input for the development of the vehicle.
文摘Two new steroidal glycosides named Lm-4 （1） and Lm-5 （2） were isolated from the tubers of Liriope muscari. Their structures were elucidated by 1D and 2D NMR, ESI/MALDIMS techniques, and chemical methods.
文摘In the past 2 years, China's new generation launch vehicles, such as the LM-6, LM-7, LM-5 and LM-11 launch vehicles, successfully made the maiden flights, which marked Chinese Long March series launch vehicles having many achievements such as the diameter of launch vehicles increased from 3.35 m to 5 m and the toxic propellants replaced with non-toxic and pollution-free propellants. This paper will introduce the features and new technology of LM-7, LM-5 and LM-11 launch vehicles, which are China's new typical generation Launch vehicles.
