Frontier technology, frontier technology, aerospace technology

(1) The development history and present situation of space technology generally think that the space below 100 km from the earth's surface is "empty" and the space above 100 km is "sky", but there is no absolute dividing line between them. The integration of air and space is the development trend of space technology in the future, and it is a major change caused by the development of modern high technology.

(2) 1903, the Wright brothers successfully developed the world's first powered plane, which realized the long-cherished dream of flying. At the beginning of the 20th century, the establishment of circulation and lift theory laid the foundation for the design of low-speed aircraft, and made heavier-than-air aircraft a reality. From the mid-1940s to 1950s, the rapid development of compressible gas dynamics theory, especially the discovery of the new concepts of transonic area rule and swept wing, helped people to break through the "sound barrier" and realize transonic and supersonic flight. In the mid-1950s, the first generation fighters with superior performance were successfully developed, such as American-made F86 and F 100, Soviet-made Mig 15 and Mig 19. During the Second World War, the demand for military aviation and the appearance and use of missile weapons prompted people to pursue higher speed. Since 1950s, supersonic aerodynamics has entered a new era. The second generation fighters with more advanced performance have been put into use one after another, such as F4, F 104 of the United States, Mig2 1 of the Soviet Union, Mig23 of France and Mirage 3.

(3) 1957 The Soviet Union launched the world's first earth satellite, and 196 1 launched the first manned spaceship "Dongfang", which is considered as the beginning of the space age. After the 1960s, the Soviet Union and the United States successively developed a series of manned spacecraft, such as: Russian manned spacecraft "Dongfang", "Ascension" and "Soyuz"; Mercury, Gemini, Apollo, etc. In the 1970s, there was an upsurge in research and development of aerospace aircraft in various countries. 198 1 year, the United States successfully launched the world's first space shuttle "Columbia". Russia also launched the space shuttle Blizzard in 1988. In aviation, the focus is on the development of high-performance combat aircraft, supersonic passenger aircraft, V/STOL aircraft and variable swept-back wing aircraft. After the 1970s, the third generation of highly mobile fighters came out one after another, such as American F 15 and F 16, Soviet Su27 and Mig29, and French Mirage 2000.

(4) The space shuttle can be reused and has strong payload capacity. The initial idea can greatly reduce the launch cost. However, in actual use, it is found that the development cost of the space shuttle is very high, the cost of each launch exceeds the previous forecast, and the failure rate is also relatively high. In 2003, after the American space shuttle Columbia crashed, the United States realized that there was an urgent need to develop new space vehicles to enter space, control space, conduct space exploration and transport people and goods to the space station.

(5) As early as the early 1990s, the United States began to implement the National Space Plane Development Plan (NASP). The project started at 1982. Because the technical reserve of scramjet as a power system was insufficient in the hypersonic Mach number range, it was difficult to break through its technical key in a short time, so it had to be dismounted at 1994, which lasted for more than 10 years and cost more than 3 billion US dollars. Since then, NASA has begun to implement the new HyperX program, which has three main objectives: first, flight verification of the design method adopted; Second, continue to develop aircraft design tools powered by scramjet; The third is to reduce the possible risks caused by inaccurate predictions of aerodynamics, propulsion system and structure/engine/structure integration. 1996, research and development of space vehicles X33 and X34 powered by rockets began. Due to the lack of research on the strength, toughness and heat resistance of new lightweight materials, it was also published in March 20001year.

(6) In June, 20065438+0, the aerospace vehicle X43A powered by scramjet made its first test flight. When the flight speed reached Ma= 1, the aircraft deviated from the predetermined orbit when leaving the B52 carrier aircraft because the booster was out of control, and had to be detonated and smashed.

(7) On March 27th, 2004, the flight test of X43A was successful. The controllable flight speed of the aircraft powered by scramjet reaches 8000 km/h (Ma=7), the flight duration is 8 seconds, and the flight altitude reaches 28000 meters. X43A is only an experimental aircraft, but there are still many problems in practical use, such as thermal protection of scramjet. At present, the X43A is designed with heat sink cooling, and the air inlet lip is open, so it is totally water-cooled. This cooling technology can maintain the flight time of about 10 second. Over time, heat dissipation is a big problem. In addition, if more practical hydrocarbon fuel is used, ignition is much more difficult than hydrogen. Further improving the flight Ma number also faces more difficulties.

(8) In recent years, the United States, Russia and other countries have never stopped researching and exploring space technology. In the new space program announced on June 5438+ 10, 2004, the United States proposed to develop a new generation of "manned exploration spacecraft" (CEV) by 20 10. A group of astronauts and equipment can be sent to space or the moon at a time, which greatly improves the function of manned spacecraft. Russia also announced in March 2004 that it was developing a new generation of spacecraft called "Space Clipper" to replace the old Soyuz. It weighs twice as much as Soyuz, can carry six astronauts and can be reused for more than 25 times. It is said that as long as the development funds can be put in place in time, it will be completed in five years.

(9) The U.S. Department of Defense has also announced that it will develop a reusable "trans-atmospheric aerospace vehicle", believing that it will become the most important new aerospace flight platform in the future, which can provide very valuable capabilities for aerospace transportation and offensive and defensive confrontation in the 2 1 century. Compared with the spacecraft and space shuttle currently used, it has outstanding advantages in launch cost, maintainability, reuse and flight performance. It can replace the launch vehicle to launch satellites with low price and high reliability, and can also replace the spacecraft or space shuttle to transport people and goods back and forth between heaven and earth. On the military side, it can quickly and flexibly enter space, achieve "global arrival" within two hours, complete reconnaissance and combat missions, and can also be used as a launching platform for various space-based combat weapons. It can also run in orbit for a long time and perform space early warning and operational command.

(10) In addition, the United States, Russia and Europe have also done a lot of work in space exploration and space station construction. In addition to exploring the moon, space exploration also launched a series of planetary probes, flying to Mars, Venus, Saturn, Jupiter and so on. Since 1962, when the Soviet Union launched the "Mars 1" probe, human beings have launched more than 30 probes to Mars, and two-thirds failed. From June to July, 2003, the United States launched the Mars probes Spirit and Opportunity. Six months later, it successfully landed on Mars in June 2004, and now it has sent back a lot of extremely precious information to the earth. In terms of space station construction, the International Space Station, jointly built by the United States, Russia, Japan, Canada and other six countries, consists of six experimental cabins, 1 living cabin, three node cabins, balance system, power supply system, service cabin and transportation system, with a total weight of 500 tons and can accommodate 7- 15 astronauts at the same time. The project started in 1998, with an estimated investment of 50 billion US dollars and a working life of over 15 years. It was originally planned to be completed in 2006, but now it seems that the progress will be delayed. In the composition of a country's comprehensive national strength, space technology occupies a very important position and is a symbol of national strength and scientific and technological level. Throughout the many local wars in recent years, all of them started with air strikes. Apart from land and sea, attacks from air and space will become the most serious threat to national security.

Take the Iraq war as an example. In 2003, the United States, Britain and other countries dispatched18,000 aircraft, and used advanced F/A 18e/F fighters for the first time. Make full use of the strong support of the integrated information system of air, space and earth, the information level of air combat weapon platform is higher than any previous war, and nearly 30,000 bombs were dropped by * * *, of which guided bombs and missiles accounted for 68%. As a result of mastering the absolute superiority of air superiority and air superiority, Saddam Hussein's regime was overthrown in less than four weeks, and the death toll was only 1 15, which fully demonstrated the role of air superiority and air superiority in modern wars.

Air and space superiority is the strategic commanding height to win victory under the condition of high-tech war in the future. As early as the 1960s, American President Kennedy said, "Whoever controls space controls the earth." Vision 2020, published by US Space Command 1998, and the Latest Space Policy of US Department of Defense, published by 1999, both proposed to "develop the ability to control space". In the next 20 years, vigorously developing space technology and improving the ability to "enter, use and control space" will become the most important issue to ensure national security and international status.

The development of space technology plays an extremely important role in national economy and social progress, and its development has greatly improved people's quality of life. Take the development of civil aviation as an example: since the 1960s, with the appearance of 150 passenger jets, air transport has become an important mode of human transport. The world's air passenger traffic increases every 10 year10.6 trillion person-kilometers, and the average annual growth rate of freight turnover reaches 5% ~ 7%. By 2020, the world air passenger traffic is expected to reach 6.4 trillion person-kilometers. From 200 1 to 2020, the total demand of global airlines for jumbo jets will exceed10.8 million, and the total value will exceed10.4 trillion US dollars. China is one of the fastest growing areas of civil aviation transportation in the world. From 65438 to 0999, the total annual transportation turnover and passenger turnover of China civil aviation have risen to the ninth and sixth places in the world. In 2003, there were 26 airports 126, with 265,438+million aircraft movements, passenger throughput1700,000 passengers and cargo and mail throughput of 5.2 million tons. Air transport is the safest of the existing modes of transportation. In 2003, there were a total of 162 air crashes and 1204 deaths in the world, reaching the lowest value since 1945. Among them, there were 25 accidents in business operation and 677 people died.

Space technology is also closely related to national economy, social development and people's lives. People are widely enjoying the achievements of space technology, such as satellite broadcasting and communication, meteorological observation and forecast, satellite navigation and positioning, earth resources survey, biological breeding, material preparation, drug synthesis and so on. Take meteorological satellites as an example. Now there are dozens of meteorological satellites in the world, forming a global observation network. 120 countries have set up meteorological satellite data receiving and utilization service stations to observe and forecast atmospheric environmental changes around the clock, and make timely and accurate forecasts of natural disasters such as typhoons, rainstorms, floods and droughts, greatly reducing casualties and property losses. Since 1988, China has launched seven Fengyun series meteorological satellites, and satellite data have played an important role in weather forecast, meteorological research, agricultural planning and disaster monitoring in China. Space breeding is another important application field of space technology. Using the characteristics of high vacuum, high cleanliness, microgravity, all kinds of cosmic rays, heavy ions, alternating magnetic fields and other space environments, mutation breeding has changed plant type, panicle type and fruit type, and the yield has been greatly improved, showing a very attractive prospect.

3. Future Prospect of Space Technology After entering the 2 1 century, advanced countries in the world pay more attention to the development of space technology. It can be predicted that in the next decade or longer (before 2020), space technology will surely make greater development. The aerospace vehicles under development and likely to enter the model development mainly include: highly mobile combat aircraft, reusable hypersonic aerospace vehicles, large-scale high-speed civil aircraft and military transport aircraft, a new generation of strategic and tactical combat weapons, military/civilian satellites, space laboratories, unmanned reconnaissance combat aircraft, armed helicopters, ground effect aircraft, micro aircraft, intelligent control variable shape aircraft, and new concept weapons such as laser and kinetic energy.

According to the forecast of "Tianyi 1", in the next decade, due to the development of aerodynamics, the drag of aircraft will decrease by 15%~20%, the structural weight of aircraft will decrease by 20% due to the progress of materials and design technology, and the accident rate of aircraft will decrease by 80% due to the improvement of component reliability and manufacturing technology. The new generation of military aircraft will have supersonic cruise, post-stall maneuver, short take-off and landing, stealth and other capabilities, equipped with more advanced electronic weapon systems, and its combat capability will be improved by 10 times compared with the existing aircraft; Civil aircraft will develop in the direction of bigger, faster, safer, more economical and less environmental pollution. Civil aircraft with 500~ 1000 seats are expected to be put into use. In space, the space transportation system, including launch vehicles, satellites, reusable trans-atmospheric aircraft and space combat aircraft, will develop in the direction of high speed, high maneuverability, high reliability, high stealth, precision strike, real-time launch on demand, reliable entry into space, rapid deployment, expansion and maintenance, low cost, strong function and reusability. Control space will become the strategic commanding height under the condition of high-tech war in the future. To control space, you must first be able to enter space. Therefore, it is an urgent task to develop the means of transportation into space. Long-range, deep and precise strikes will become the main body of offensive forces; There is an urgent need to establish an all-round, multi-level, flexible and rapid response air and space defense system.

Four. China's space technology faces challenges. Shortly after the founding of New China in 1950s, the development of space industry was highly valued by the Party and the country. 1956, the Outline of Medium and Long-term Scientific and Technological Development Plan lists rocket and propulsion technology as one of the seven key projects. Over the past 50 years, China's space industry has developed rapidly and made great achievements. In aviation, 1954 made its first flight, 1956 made a domestic J-5 jet, 1960 made a Qiang-5 aircraft in China, and 1984 made a J-8 aircraft in China. In recent years, China has successfully developed J- 10 aircraft by itself, and its tactical and technical performance has reached the level of the third-generation fighter currently in service abroad.

In space, 1960 China successfully launched its own ballistic missile, which opened a new era for China's space flight. 1965165438+1in October, DF 1 short-range ballistic missile was successfully developed,19665438+in February, DF2 medium-sized missile developed by China was successfully tested, 1970. 1 In April, 1970, the Long March1launch vehicle was successfully launched, and by the mid-1980s, a series had initially formed. After 40 years of hard work, we have successfully developed a variety of launch vehicles and launched more than 70 spacecraft, including near-earth satellites, geosynchronous, sun-synchronous and manned spacecraft. 1990 entered the international commercial satellite launch market and successfully launched more than 20 foreign satellites. China has made remarkable achievements in space flight. 1992, China began to develop manned space flight, and it was determined that manned space flight began with manned spacecraft.

1September, 1992, China's manned spaceflight project was approved and implemented. After 7 years' demonstration, research, design, construction and test, 1999 165438 1 On October 20th, the "Shenzhou 1" spacecraft was launched, and it landed in a predetermined area after normal operation in space1days. The flight test of "Shenzhou 1" to "Shenzhou IV" has accumulated a lot of practical experience, which laid the foundation for manned flight. In 2003, Shenzhou 5 was successfully launched in June 5438+1October 65438+May (Figure 26), and China achieved manned space flight for the first time. June 65438+1October 65438+June 2003, Shenzhou 5 successfully returned to the ground, and the first manned space flight was a complete success.

Figure 26 "Shenzhou 5" successfully launched Figure 27 "Shenzhou 5" successfully returned.

In addition, in 2000, China built a regional Beidou navigation test satellite system consisting of two satellites. On May 26th, 2003, China successfully sent the third Beidou 1 navigation and positioning satellite into space in xichang satellite launch center, which indicated that China successfully established its own satellite navigation system-the first generation Beidou satellite navigation and positioning system.

In space exploration, China's "Double Star Program" cooperated with the European Space Agency uses two satellites with intersecting orbits to conduct large-scale magnetospheric space synchronous exploration. Together with the four satellites "Tuanxing II" launched by the European Space Agency, the binary star will form the first six-point stereo detection system from the sun to earth space. This is the first scientific exploration satellite project that China cooperates with the European Space Agency, and it is also the first real space exploration program in China's space history.

Regarding the future development of China's space industry, the "China Space White Paper" issued by the National Space Administration announced that China will vigorously develop the Earth observation satellite system that can run stably for a long time in the future 10 or longer; Establish an independent satellite broadcasting communication system and a navigation and positioning satellite system; Establish a new satellite system for scientific exploration and technical test; Further develop manned spaceflight technology, space laboratory, lunar exploration and deep space exploration technology, manned spaceflight and transportation system between heaven and earth, and integrated information system between heaven and earth. Military aerospace (all kinds of reconnaissance, communication, navigation satellites and other spacecraft) and air-space combat weapons will also be greatly developed under the impetus of huge demand.

On March 1 2003, China National Space Administration announced the launch of the lunar exploration project, which was named "Chang 'e Project". After half a century's efforts in space technology, the time and conditions for China to implement the plan are ripe, the path for lunar exploration has been determined, and some key technologies have also made breakthroughs. It is expected that China will launch a lunar exploration satellite within two years.

Reusable spacecraft has attracted worldwide attention because of its advantages in launch cost, launch preparation period, payload capacity and operational efficiency. China is also actively carrying out research work in this field.

The outstanding feature of the future aerospace vehicle platform is that it will adopt lifting body configuration with large lift-drag ratio. Its structure is ultra-light, high-strength, functional/structural integration, with the most advanced hypersonic power system, structural thermal protection system, control system and safety guarantee system. The complex shape and flight environment of this kind of aircraft have caused a series of extremely complex flow phenomena, such as shock wave, separation, vortex, turbulence, chemical reaction and plasma flow, force, heat, light and electromagnetic multi-field coupling and so on. Their unique service conditions and specific combat mission requirements have led to a new class of topics that challenge the existing scientific knowledge, such as: strong-short time load coupling effect, unbalanced coupling effect between high strain rate and high temperature rise rate and structure, intelligent materials and structures, intelligent autonomous control technology, micro-fluid mechanics and micro-system dynamics.

Verb (abbreviation of verb) Conclusion 265438+In the first 50 years of the 20th century, the development of space technology will be very similar to that of aviation in the first half of the 20th century. In the next few years, with the support of the powerful air/sky/ground integrated information system, the war will be all-directional, in-depth and three-dimensional, and the traditional single weapon independent combat mode will be changed into a five-in-one system confrontation of sea, land, air, sky and electricity, and an integrated system of attack and defense. It will gradually become a strategic behavior to develop from air (air) warfare support to air (air) warfare and implement air (air) to ground long-range precision strike. All these put forward many strict requirements for the development of space technology.

Space technology is a high-tech field involving many disciplines, and the basic key technical problems faced by the development of space vehicles are also various. Our existing scientific and technological foundation is not enough to solve all kinds of complicated and difficult problems satisfactorily. It is still an urgent task to strengthen basic theoretical research and continuously improve and improve the ability of ground simulation experiment, numerical calculation and theoretical analysis. Here, we should especially emphasize the importance of the organic combination and coordinated development of basic research and engineering application. As a high-tech industry, aerospace industry should be at the forefront in basic research.

It is necessary to "put people first", encourage innovation, vigorously create subjective and objective conditions and a relaxed environment to encourage innovation, and actively train a large number of outstanding young aerospace science and technology talents. Inherit and carry forward the spirit of "two bombs and one satellite" and "manned space flight" and work hard to accelerate the development of China's space industry!