玉盾坐在赵影的面前,手里继续把玩这那个银光闪闪的小型发动机。”哥,我带了一点东西,你看一下吧。”玉盾从包中抽出了一个牛皮纸材质的保密文件夹,其厚度就几乎能够说明它的重要性。
”这是什么?”赵影转下白线,从中抽取大量的资料。
abstract
according to the classic theory of electromagnetic (em) fields, we develop a propellantless microwave thruster system that can convert microwave power directly into thrust without the need of propellant. it is expected to be useful for spacecraft. different from conventional space plaa propulsion, the system can obviate a large propellant storage tank and the issues related to plaa plume interference with the spacecraft surface. different from huge solar sails and microwave-propelled sails, the system uses a cylindrical tapered resonance cavity as a thruster and uses an integrated microwave source to generate continuous em wave so that the em wave is radiated into and then reflected from the thruster to form a pure standing wave with amplified wave amplitude. the pure standing wave produces a non-uniform em pressure distribution on the inner surface of the thruster. consequently, a non-zero net em thrust exerting on the symmetric axis and directing to the minor end plate of the thruster appears. in experiments a magnetron is used as a microwave source with an output microwave power of 2.45 ghz frequency. the generated net em thrust is measured using a force-feedback test stand. the developed thruster system is experimentally demonstrated to produce thrust from 70 to 720 mn when the microwave output power is from 80 to 2500 w.constraints such as thermal control and observation missions require that spacecraft orbiting mercury use a sun-synchronous orbit, but because mercury's flat rate is veryall, it is necessary to use external force forced orbital precession to form a sun-synchronous orbit. in this paper, the sun-synchronous orbit of mercury, a solar sail spacecraft, is studied. firstly, the sun-synchronous circular orbit is yzed, and the relationship between the orbit radius and the characteristic acceleration of the solar sail spacecraft is established. low orbit circular orbits require solar sail spacecraft to provide large characteristic acceleration and two rapid attitude maneuvers of the solar sail during one orbital period. the sun-synchronous elliptical orbit is then yzed to establish the relationship between the altitudes of the near-mercury and far-mercury points of the orbits and the characteristic acceleration of the solar sail spacecraft. the use of solar synchronous elliptical orbit for mercury detection can reduce the characteristic acceleration of solar sail spacecraft and do not require rapid attitude maneuvering, thereby reducing the requirements of solar sail spacecraft for lightweight structural materials and attitude control systems.(翻译自己找吧)……
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”这是什么?”赵影转下白线,从中抽取大量的资料。
abstract
according to the classic theory of electromagnetic (em) fields, we develop a propellantless microwave thruster system that can convert microwave power directly into thrust without the need of propellant. it is expected to be useful for spacecraft. different from conventional space plaa propulsion, the system can obviate a large propellant storage tank and the issues related to plaa plume interference with the spacecraft surface. different from huge solar sails and microwave-propelled sails, the system uses a cylindrical tapered resonance cavity as a thruster and uses an integrated microwave source to generate continuous em wave so that the em wave is radiated into and then reflected from the thruster to form a pure standing wave with amplified wave amplitude. the pure standing wave produces a non-uniform em pressure distribution on the inner surface of the thruster. consequently, a non-zero net em thrust exerting on the symmetric axis and directing to the minor end plate of the thruster appears. in experiments a magnetron is used as a microwave source with an output microwave power of 2.45 ghz frequency. the generated net em thrust is measured using a force-feedback test stand. the developed thruster system is experimentally demonstrated to produce thrust from 70 to 720 mn when the microwave output power is from 80 to 2500 w.constraints such as thermal control and observation missions require that spacecraft orbiting mercury use a sun-synchronous orbit, but because mercury's flat rate is veryall, it is necessary to use external force forced orbital precession to form a sun-synchronous orbit. in this paper, the sun-synchronous orbit of mercury, a solar sail spacecraft, is studied. firstly, the sun-synchronous circular orbit is yzed, and the relationship between the orbit radius and the characteristic acceleration of the solar sail spacecraft is established. low orbit circular orbits require solar sail spacecraft to provide large characteristic acceleration and two rapid attitude maneuvers of the solar sail during one orbital period. the sun-synchronous elliptical orbit is then yzed to establish the relationship between the altitudes of the near-mercury and far-mercury points of the orbits and the characteristic acceleration of the solar sail spacecraft. the use of solar synchronous elliptical orbit for mercury detection can reduce the characteristic acceleration of solar sail spacecraft and do not require rapid attitude maneuvering, thereby reducing the requirements of solar sail spacecraft for lightweight structural materials and attitude control systems.(翻译自己找吧)……
本章未完,请点击下一页继续阅读!
本站网站:www.123shuku.com