Resolve the long seventh: with 6 120 tonnes of liquid oxygen-kerosene engine

20:00 June 25, China's manned space program to launch cargo ships and the newly developed "long seventh" Wenchang in Hainan spaceport for launch vehicle blasted off about 603 seconds after load combinations and rockets have successfully separated into elliptical orbit perigee of and an apogee of 200-kilometer 394-kilometer, "the long seventh" rocket launch a great success for the first time. News Agency reporters He Weiguo photo video: long seventh rocket ignition launch crowd applauded source: China News Network
New in XI ' an, June 25 (reporter Tian Jin), the night of 25th, developed by the China Aerospace Science and Technology Corporation six Lox/kerosene engines, elected China's new medium launch vehicle "the long seventh," the success of the first flight. Rocket engine expert Luan Xiting in XI ' an, said that "the long seventh" rocket boosters and the core level, was first used by 6 120 tonnes of liquid oxygen-kerosene engine.
According to reports, "the long seventh" is a next-generation medium-launch vehicles in China's long March rocket family, up to a diameter of 3.35 meters of core level and 4 booster diameter of 2.25 meters, and arrow 53.1 m long, power system used in space base in XI ' an China Aerospace Science and Technology Corporation, six homes developed rocket engine.
"6 120 tonnes of liquid oxygen-kerosene engine also generates huge energy output, shook up shake the feeling, bottom block heat flow density is higher than that of existing rockets the rocket level above 35%. "Rocket engine expert, said Liu Luan Xiting, Deputy Director of China Aerospace Science and Technology Corporation, the rocket's boosters and the core level, a total of 6 120 tons of Lox/kerosene engines, secondary use of core 4 18 tonnes of liquid oxygen-kerosene engine, with a near-Earth orbit and 13.5 tons, 700-kilometer sun-synchronous orbit of 5.5 tons of carrying capacity.
Compared with conventional engines, "the long seventh" used liquid oxygen-kerosene engine uses the world's most advanced technology of high-pressure staged combustion cycle. 120 tons of liquid oxygen-kerosene engine, self starter, higher reliability.
Staged combustion cycle is after gas turbines that work into the combustion chamber, post-combustion, more propellant energy to good use. "A higher overall efficiency of staged combustion cycle, but the structure is more complex, difficult to design. "Luan Xiting said afterburning engine must first solve their own starting problem, need special gunpowder China engine starter device, and lox/kerosene engines achieve their own starter. "It's like hand tractors to twist the key to start the car. ”
Meanwhile, Lox/kerosene engines has the ability to work multiple times, you can reuse of engines based on this technology, enabling the rocket to achieve world travel can be reused.
Luan Xiting said, as staged combustion cycle with advanced technology, their starting seven advantages of technology, Lox/kerosene engines will become the main driver of China's new generation of three rocket. Meanwhile, researchers in the 500-ton for higher thrust Lox/kerosene engine key technique research, will be established in the future to meet the development needs of China's space industry by high performance liquid oxygen-kerosene engine.
Reporter understand to, the "March seventh," flew, China space technology group six Hospital except provides latest development of green environmental liquid oxygen kerosene engine outside, also provides has "space Ferry car" main power system, that "March seventh," rocket above level main engine, its up moving times, and in rail time, and than rushed performance, representative has China with type engine of highest index, fill has China space above level power technology field blank, into has international advanced level.
Author: Tian
(Editors: Pan Yi burn UN657)
2016-06-25 21:38:31
China News Network

解析长征七号：首用6台120吨液氧煤油发动机

　　6月25日20时00分，中国载人航天工程为发射货运飞船而全新研制的“长征七号”运载火箭在海南文昌航天发射场点火升空，约603秒后，载荷组合体与火箭成功分离，进入近地点200千米、远地点394千米的椭圆轨道，“长征七号”运载火箭首次发射圆满成功。 中新社记者 何卫国 摄 视频：长征七号运载火箭点火发射 群众鼓掌欢呼来源:中国新闻网


　　中新社西安6月25日电 (记者 田进)25日晚，由中国航天科技集团公司六院研制的液氧煤油发动机，推举中国新一代中型运载火箭“长征七号”首次飞行获得成功。火箭发动机专家栾希亭在西安透露，“长征七号”火箭助推器与芯一级，首次使用了6台120吨液氧煤油发动机。

　　据介绍，“长征七号”是中国长征火箭家族中的新一代中型运载火箭，由直径3.35米的芯级和4个直径2.25米的助推器组成，全箭长53.1米，动力系统全部采用位于西安航天基地的中国航天科技集团公司六院研制的火箭发动机。

　　“6台120吨液氧煤油发动机同时工作产生巨大的能量输出，震动起来就是地动山摇的感觉，火箭一级底部阻塞热流密度比现役火箭高35%以上。”火箭发动机专家、中国航天科技集团公司六院副院长栾希亭说，此次火箭的助推器与芯一级，共使用6台120吨液氧煤油发动机，芯二级使用4台18吨液氧煤油发动机，具备近地轨道13.5吨、700千米太阳同步轨道5.5吨的运载能力。

　　与常规发动机相比，“长征七号”使用的液氧煤油发动机采用了世界上最先进的高压补燃循环技术。120吨液氧煤油发动机，采用自身起动，可靠性更高。

　　补燃循环是燃气经涡轮做功后进入燃烧室，进行二次燃烧，更充分地利用推进剂能量。“补燃循环方式的综合效率更高，但结构较为复杂，设计难度大。”栾希亭说，补燃发动机首先要解决自身起动难题，中国以往的发动机需要靠专门火药起动器等装置，而液氧煤油发动机实现了自身起动。“这好比将手摇拖拉机改成了一拧钥匙就能启动的汽车。”

　　同时，液氧煤油发动机具有多次工作的能力，可以在此技术基础上研制重复使用的发动机，使运载火箭能够实现天地往返的可重复使用。

　　栾希亭说，因为具有先进的补燃循环技术、自身起动技术等七大突出优势，液氧煤油发动机将成为中国新一代三型运载火箭的主动力。同时，科研人员还在进行500吨级等更大推力的液氧煤油发动机的关键技术攻关，未来将建立满足中国航天事业发展需要的液氧煤油发动机型谱。

　　记者了解到，此次“长征七号”首飞，中国航天科技集团六院除提供最新研制的绿色环保液氧煤油发动机外，还提供了“太空摆渡车”主动力系统，即“长征七号”运载火箭上面级主发动机，其起动次数、在轨时间、比冲性能等代表了中国同类型发动机的最高指标，填补了中国航天上面级动力技术领域空白，步入了国际先进水平。

　　作者：田进
(责任编辑：潘奕燃 UN657)
2016-06-25 21:38:31
中国新闻网