1. Piston engine period

● Early liquid-cooled engines dominated Our ancestors had long dreamed of flying freely in the sky like birds, and had tried various things, but most of them failed because the power source problem was not solved. Initially someone put a specially designed steam engine on the plane to try, but because the engine was too heavy, it was not successful. By the end of the 19th century, when the internal combustion engine began to be used in automobiles, people associated with the use of internal combustion engines on aircraft as a source of power for aircraft flight, and began experiments in this area.

In 1903, the Wright brothers successfully used a four-cylinder, horizontal in-line water-cooled engine to successfully test their flight on the "Flighter One" aircraft. The engine emits only 8.95 kW and weighs 81 kg with a power-to-weight ratio of 0.11 kW/daN. The engine drives two wooden propellers with a diameter of 2.6 m through a chain like the two bicycles. The first flight has a left time of only 12s and a flight distance of 36.6m. But it is the first time in human history to have a dynamic, manned, sustained, stable, and operationally successful flight over an air vehicle.

Later, with the use of aircraft for war purposes, aviation began to flourish, especially in Europe, and France was at the leading position. Although the United States invented the power plane and built the first military aircraft, there was not even a new aircraft available at the time of the war. Among the 6,287 aircraft of the US Air Force Squadron on the front line, there were 4,791 French aircraft, such as the "Sped" fighter equipped with the Ispano-Siza V-type liquid-cooled engine. The power of this engine has reached 130~220kW, and the power-to-weight ratio is about 0.7kW/daN. The speed of the aircraft exceeds 200km/h and the ceiling is 6650m.

At that time, the flight speed of the aircraft was still relatively small, and the air-cooled engine was difficult to cool. For cooling, the engine is exposed and the resistance is large. Therefore, most aircraft, especially fighters, use liquid-cooled engines. During the period, in 1908, the French Segan brothers invented the rotary cylinder air-cooled star engine once popular. This type of engine with fixed crankshaft and cylinder rotation is limited by the increase in power, and exits the historical stage after the cooling problem of the air-cooled star engine of the fixed cylinder is solved.

● Important technical inventions between the two world wars Between the two world wars, several important inventions emerged in the field of piston engines: the engine fairing not only reduced the aircraft resistance, but also solved the cooling difficulties of the air-cooled engine. The problem is that even two or four rows of cylinders can be designed to create conditions for increased power; the exhaust turbocharger increases the intake pressure at high altitudes and improves the engine's high altitude performance; the variable pitch propeller can increase the propeller Efficiency and engine power output; the cooling exhaust valve filled with sodium metal solves the problem of overheating of the exhaust valve; the mixture of water and methanol in the cylinder can increase power by one-third in a short time; The alkane fuel improves the antiknock of the fuel, so that the pressure before combustion in the cylinder is gradually increased from 2 to 3 to 5 to 6, or even 8 to 9, which not only increases the power but also reduces the fuel consumption.

● Since the mid-1920s, air-cooled engines have developed rapidly, but liquid-cooled engines still have a place. During this period, after the fairing solved the problem of resistance and cooling, the air-cooled star engine was rigid and light. Rapid development of reliability, maintainability and survivability, and great potential for power growth, and the beginning of replacing liquid-cooled engines on large bombers, transport aircraft and ground attack aircraft. In the mid-1920s, the United States Wright Company and Puhui Company successively developed a single row of "Cyclone" and "Hurricane" and "Wasp" and "Bumblebee" engines with a maximum power of over 400 kW and a power-to-weight ratio of over 1 kW/ daN. By the time of the outbreak of the Second World War, the engine power had been increased to 600-820 kW due to the successful development of the dual-exhaust cold star engine. At this time, the flight speed of the propeller fighter has exceeded 500km/h and the flying height has reached 10,000m.

During the Second World War, the air-cooled star engine continued to develop in the direction of high power. Among them, the famous double-row "double wasp" (R-2800) and the four-row "big wasp" (R-4360) are listed. The former was finalized on July 1, 1839, and the power at the beginning was 1230kW, a total of 10 series of dozens of modified models, the final power reached 2088kW, used for a large number of military and civilian aircraft and helicopters. For the P-47 fighter alone, 24,000 R-2800 engines were produced, of which P-47 J The maximum speed of 805km / h. Although controversial, it is said to be the fastest flying fighter in the Second World War. This engine has a special position in aviation history. At the aviation museum or aviation exhibition, R -2800 is always placed in a central position. Even some aviation history books say that if there is no R-2800 engine, it will be much more difficult for the allies to win in World War II. The latter has four rows of 28 cylinders, displacement It is 71.5L and has a power of 2200~3000kW. It is the world's most powerful piston engine for some large bombers and transport aircraft. In 1941, the B-36 bomber designed around six R-4360 engines was one of the few propulsions. One, but not put into use. Wright The R-2600 and R-3350 engines are also well-known dual-exhaust cold-star engines. The former was introduced in 1939 and has a power of 1120 kW. It is used in the first carrier-buy passengers to fly across the Atlantic. Four seaplanes and some smaller torpedo machines, bombers and attack aircraft. The latter was put into use in 1941, initially with a power of 2088 kW, mainly used for the famous B-29 "Aerial Fortress" strategic bomber. R-3350 After the war, an important modification was developed, the turbo-combined engine. The exhaust of the engine drives three circumferentially distributed exhaust turbines, each of which can deliver 150 kW of power at maximum. Thus, the power of the R-3350 Increased to 2535kW, the fuel consumption rate is as low as 0.23kg / (kW · h). In September 1946, the P2V1 "Neptune" aircraft equipped with two R-3350 turbo combined engines created a world record of 18090km airborne non-oiled flight distance. The competition between liquid-cooled and air-cooled engines continued in the Second World War. Although liquid-cooled engines have many shortcomings, their small windward area is particularly advantageous for high-speed fighters. Moreover, the flight of fighters The degree is high, the threat of ground fire is small, and the weakness of the liquid-cooled engine is not prominent. Therefore, it is used in many fighters. For example, four of the five most productive fighters in the United States used this war. Liquid-cooled engine. Among them, it is worth mentioning that the Merlin engine of the British Roy-Royce company. When it first flew on the "Hurricane" fighter in November 1935, the power reached 708kW; in 1936, it flew on the "Spitfire" fighter. At that time, the power was increased to 783 kW. Both aircraft were famous fighters during the Second World War, with speeds of 624 km/h and 750 km/h respectively. The power of the Merlin engine reached 1238 kW at the end of the war and even recorded a record of 1491 kW. The American Parker Company patented the Merlin engine to modify the P-51 Mustang fighter, making a normal aircraft the best fighter in wartime. The "Wild Horse" fighter uses an uncommon five-bladed propeller. After installing the Merlin engine, the maximum speed is 760km/h and the flying height is 15000m. In addition to having the fastest speed of the time, another outstanding advantage of the "Bronco" fighter is its amazing long-range capability, which can escort allied bombers to Berlin. By the end of the war, the "Wild Horse" fighters shot down 4,950 enemy aircraft in air combat, ranking first in the European battlefield. In the battlefields of the Far East and the Pacific, due to the participation of the "Wild Horse" fighters, the dominance of the Japanese "Zero" fighters was ended. The aviation history community regards the "Wild Horse" aircraft as the pinnacle of the propeller fighter.

The most important technological advances after the start of the Second World War and after the war were direct oil injection, turbo combined engines and low-pressure ignition.

Driven by the two world wars, the performance of the engine has improved rapidly. The power of the single machine has increased from less than 10 kW to about 2,500 kW. The power-to-weight ratio has increased from 0.11 kW/daN to about 1.5 kW/daN. The displacement is increased by several kilowatts to four or fifty kilowatts, and the fuel consumption rate is reduced from about 0.50 kg/(kW·h) to 0.23 to 0.27 kg/(kW·h). The renovation life has been extended from tens of hours to 2000~3000h. By the end of the Second World War, the piston engine had developed quite mature, and the speed of the propeller-powered propeller aircraft increased from 16km/h to nearly 800km/h and the flight altitude reached 15000m. It can be said that the piston engine has reached the peak of its development.

● Piston engine in the jet era After the end of the Second World War, the jet-jet engine was invented, and the piston engine gradually withdrew from the main aviation field, but the horizontal-to-cylinder piston engine with power less than 370 kW Still widely used in light low-speed aircraft and helicopters, such as administrative machines, agricultural and forestry machines, exploration machines, sports machines, private aircraft and various drones, rotary piston engines have emerged on drones, and NASA is still developing in the United States. Aviation kerosene's new two-stroke diesel engine is used by the next generation of small general-purpose aircraft.

NASA has implemented a general aviation propulsion program to provide power technology for future versatile light aircraft that are safe, comfortable, easy to operate, and inexpensive. This light aircraft is roughly 4-6 seats and has a flight speed of around 365 km/h. One solution is to use a turbofan engine, which is slightly larger with six airplanes and has a higher speed. Another option is to use a Diesel cycle piston engine with four seats and a low speed. The engine requirements are: 150 kW; fuel consumption 0.22 kg / (kW · h); meet future emissions requirements; manufacturing and maintenance costs are reduced by half. By the year 2000, the program had been tested on the ground for more than 500 hours, with a power of 130 kW and a fuel consumption rate of 0.23 kg/(kW·h).

2. Gas turbine engine period

The second period has been since the end of the second design war. For 60 years, aviation gas turbine engines have replaced piston engines, creating a jet era that dominates aviation power. Driven by technological developments (see Table 1), turbojet engines, turbofan engines, turboprop engines, propeller engines and turboshaft engines play their respective roles in different flight areas at different times, enabling aircraft performance across One new step after another.

● turbojet/turbofan engine The Whitby of the United Kingdom and O'Hay of Germany successfully developed the centrifugal turbojet engines WU and HeS3B on July 14, 1937 and September 1937, respectively. The former thrust was 530daN, but the Ghost E28/39 aircraft that was first tested on May 15, 1941 was equipped with its improved W1B with a thrust of 540 daN and a thrust-to-weight ratio of 2.20. The latter thrust was 490daN, and the thrust-to-weight ratio was 1.38. On August 27, 1939, it was first installed on Henkel's He-178 aircraft. This is the world's first successful flight test aircraft, creating a new era of jet propulsion and a new era in aviation.

The world's first practical turbojet engine was the Eumo-004 in Germany. The bench test began in October 1940. The thrust reached 980 daN in December 1941 and was installed in Messerschmitt Me- on July 18, 1942. The test flight on the 262 plane was successful. From September 1944 to May 1945, Me-262 shot down 613 Allied aircraft and lost 200 of its own (including non-combat losses). The first practical turbojet in the UK was the Willard, launched in April 1943 by Rolls-Royce, with a thrust of 755 daN and a thrust-to-weight ratio of 2.0. The engine was equipped with a "Meteor" fighter when it was put into production that year and was handed over to the British Air Force in May 1944. The aircraft successfully intercepted the German V-1 missile over the English Channel.

After the war, the United States, the Soviet Union, and the French developed their first generation turbojet engines by buying patents or using information and personnel obtained from Germany. Among them, the general-purpose J47 axial-flow turbojet engine of the United States General Electric Company and the RD-45 centrifugal turbojet engine of the Soviet Klimov Design Bureau have a thrust of about 2650 daN, and the thrust-to-weight ratio is 2~3, which were respectively in 1949. And served in the 1948 on the F-86 and MiG-15 fighters. These two planes launched an air battle between you and the dead during the Korean War. In the early 1950s, the use of the afterburner allowed the engine to significantly increase the thrust in a short period of time, providing sufficient thrust for the aircraft to break through the sound barrier. Typical engines are the J57 of the United States and the RD-9B of the Soviet Union. Their afterburning thrusts are 7000 daN and 3250 daN, respectively, and the thrust-to-weight ratio is 3.5 and 4.5 respectively. They are mounted on the supersonic single-engine F-100 and twin-engine MiG-19 fighters.

In the late 1950s and early 1960s, countries developed a number of turbojet engines for aircraft above M2, such as J79, J75, Evan, Olympus, Ata 9C, R-11 and R-13. Has reached 5~6. The J58 and R-31 turbojet engines for the M3 class 1 aircraft were also developed in the mid-1960s. By the early 1970s, the Olympus 593 turbojet engine for the "Concorde" supersonic passenger aircraft was finalized with a maximum thrust of 17,000 daN. Since then, no more important turbojet engines have been introduced.

The development of turbofan engines began with civilian engines. The world's first turbofan engine was the 1959 British Conway, with a thrust of 5730 daN for VC-10, DC-8 and Boeing 707 passenger aircraft. The bypass ratio is 0.3 and 0.6, and the fuel consumption rate is 10% to 20% lower than that of the turbojet engine in the same period. In 1960, the United States successfully developed the JT3D turbofan engine based on the JT3C turbojet engine. The thrust exceeded 7700 daN and the bypass ratio was 1.4. It was used for Boeing 707 and DC-8 passenger aircraft and military transport aircraft.

Later, the turbofan engine developed in two directions: a military afterburner with a low bypass ratio and a civilian engine with a high bypass ratio. In the low-caliber ratio military turbo turbofan engine, in the 1960s, the British and American developed the Spey-MK202 and TF30 on the basis of the civil turbofan engine, respectively, for the "Ghost" F-4M purchased in the UK. /K fighter and the US F111 (later used for the F-14 fighter). Their thrust-to-weight ratio is similar to that of the turbojet engine of the same period, but the intermediate fuel consumption rate is low, which greatly increases the aircraft's range. In the 1970s and 1980s, countries developed turbofan engines with a weight ratio of 8, such as F!00, F404, and F110 in the United States, RB199 in the Western European countries, and RD-33 and AL-31F in the former Soviet Union. They are equipped with third fighters currently on the front line, such as the F-15, F-16, F-18, "Gale", MiG-29 and Su-27. At present, the turbofan engine with a weight ratio of 10 is developed and will be put into service. They include the F-22/F119 in the United States, the EFA2000/EJ200 in Western Europe, and the "Gust"/M88 in France. Among them, F-22/F119 has the representative characteristics of the fourth generation fighters - supersonic cruise, short range landing, super maneuverability and stealth ability. The JSF power unit F136, which is supersonic vertical take-off and short-range landing, is under development and is expected to be commissioned from 2010 to 2012.

Since the first generation of high-duct ratio (4~6) turbofan engines with thrusts above 20,000 daN in the 1970s, a new era of large-scale wide-body aircraft has been created. Later, a high bypass ratio turbofan engine with different thrust levels of less than 20000 daN was developed, which is widely used in various trunk and regional passenger aircraft. The CFM56 series of 10,000~15000daN thrust stages has produced more than 13,000 units and has created a record of over 30,000 hours onboard. Since the civil turbofan engine is still in use, it has reduced the cruise fuel consumption rate by half, noise by 20dB, CO, UHC, and NOX by 70%, 90%, and 45%, respectively. In the mid-1990s, the second-generation high-bridge ratio (6~9) turbofan engine equipped with the Boeing 777 was used with a thrust of more than 35,000 daN. Among them, General Electric GE90-115B created a world record of 59,900 daN engine thrust in February 2003. At present, Puhui Company is developing a new generation of turbofan engine PW8000. This gear-driven turbofan engine has a thrust of 11 000~16 000 daN, a bypass ratio of 11, and a fuel consumption rate of 9%.

● Turbo/Vortex Engine In 1942, the UK began to develop the world's first turboprop engine, Mamba. The aircraft is mounted on the Navy "Tang Ge" carrier-based anti-submarine aircraft. Later, the United Kingdom, the United States and the former Soviet Union successively developed a variety of turboprop engines, such as Dart, T56, AI-20 and AI-24. These turboprop engines have low fuel consumption, high takeoff thrust, and are equipped with some important transporters and bombers. The turboprop engine T56/501, which the United States served in 1956, was installed on the C-130 transport aircraft, the P3-C reconnaissance aircraft and the E-2C early warning aircraft. It has a power range of 2580-4414 kW and has a number of military and civilian series. It has produced more than 17,000 units and exported to more than 50 countries and regions. It is one of the most produced turboprop engines in the world and is still in production. . The former Soviet Union's HK-12M has a maximum power of 11,000 kW and is used in the Figure -20 "Bear" bomber, the An-22 military transport aircraft and the Tu-114 civilian transport aircraft. Due to the limitations of the propeller in terms of power absorption, size and flight speed, turboprop engines are gradually being replaced by turbofan engines on large aircraft, but there is still a place on small and medium-sized transport aircraft and general-purpose aircraft. Among them, Canada's PT6A engine is a typical representative. In the past 40 years, this engine series with a power range of 350~1100kW has developed more than 30 models for nearly 100 kinds of aircraft in 144 countries, producing a total of 30,000. More than one. In the 1990s, the United States developed the AE2100 for the new generation of high-speed regional aircraft based on the T56 and T406. It is the most advanced turboprop engine with a power range of 2983 to 5966 kW and an extremely low take-off fuel consumption rate of 0.249 kg/ (kW·h).

Recently, the four Western European countries decided to develop the TP400 turboprop engine for the European medium-sized military transport aircraft A400M. The engine is based on the French M88 core machine with a power of 7460 kW and is scheduled for finalization in 2008.

In the late 1980s, a generation of paddle engine heat between the turboprop engine and the turbofan engine was set off. Some well-known engine companies have carried out predictions and tests to varying degrees, including General Electric's UDF GE36, which has undergone flight tests. For various reasons, only the Russian-Ukrainian An-70/D-27 entered the engineering development and planned to produce equipment and troops. However, due to the aging of aircraft technology, engine noise does not meet European standards and there are many problems in the test, the Russian and Russian sides recently decided to give up the equipment.

After the successful launch of the 206 kW Abdul I-type turboshaft engine in 1950 and the US S52-5 helicopter, the turboshaft engine gradually replaced the piston engine in the helicopter field. The most important form of power. For half a century, turboshaft engines have been successfully developed for four generations, and the power-to-weight ratio has increased from 2kW/daN to 6.8~7.1 kW/daN. The third-generation turboshaft engine was designed in the 1970s and put into production in the 1980s. The main representative models are Makila, T700-GE-701A and TV3-117VM, equipped with AS322 "Super Puma", UH-60A, AH-64A, Mi-24 and Card-52. The fourth-generation turboshaft engine was a new generation engine developed in the late 1980s and early 1990s. The representative models are RTM322 jointly developed by Britain and France, T800-LHT-800 from the United States, and MTR390 jointly developed by Germany and France. Russian TVD1500 for NH-90, EH-101, WAH-64, RAH-66 "Comanche", PAH-2/HAP/HAC "Tiger" and Card-52. The world's largest turboshaft engine is the Ukrainian D-136, with a take-off power of 7,500 kW. The Mi-26 helicopter with two engines can carry 20 tons of cargo. The tilting rotorcraft V-22 powered by the T406 turboshaft engine broke the upper limit of the 400 km/h flight speed of the conventional rotorcraft and increased to 638 km/h.

Currently, the United States is preparing to use the results of the first and second phases of the High Performance Turbine Engine Technology (IHPTET) program to develop the UH-60A "Black Hawk" / AH-64A "Apache" improved power. -- Shared Engine Project (CEP). CEP's goal is to reduce fuel consumption by 25-30%, increase work-to-weight ratio by 60%, reduce procurement and maintenance costs by 20%, and increase helicopter range by 60% or load by 70%, while reducing logistics and maintenance. burden. The production engine of the CEP project has a power limit of 2240 kW.

To meet the power needs of the Future Transportation Rotorcraft (FTR), an engine verification program using IHPTET Phase II and Phase III technology will begin in fiscal 2004. The engine has a power of 7,460 kW and its engineering and manufacturing (EMD) will be carried out in the 2008-2010 fiscal year. The FTR is expected to triple the range or double the load compared to today's heavy-duty helicopters.

Significant technological advances in the 60 years since the advent of aviation gas turbine engines can be indicated by the following figures:

The serviced fighter's engine thrust-to-weight ratio has increased from 2 to 7-9, and has been finalized and will be put into use up to 9~10. The maximum thrust of the civil large bypass ratio turbofan engine has exceeded 50,000 daN, and the cruise fuel consumption rate has dropped from 1.0 kg/(daN·h) to 0.55 kg/(daN·h) in the 1950s turbojet engine, and the noise has dropped by 20 dB. CO, UHC and NOx decreased by 70%, 90% and 45%, respectively.

The power-to-weight ratio of the turboshaft engine in service is increased from 2kW/daN to 4.6~6.1 kW/daN, which has been finalized and will be put into use at 6.8~7.1 kW/daN.

The reliability and durability of the engine are doubled. The airborne parking rate of military engines is generally 0.2~0.4/1 000 engine flight hours, and the civil engine is 0.002~0.02/1 000 engine flight hours. The final engine of the fighter engine is required to pass the 4300~6000TAC cycle test, which is equivalent to more than 10 years of normal use, and the life of the hot end parts reaches 2 000h; the life of the hot end parts of the civil engine is 7000~10000 h, and the life of the whole machine reaches 15000~20. 000 h, also used for about 10 years.

In short, the aviation turbine engine has developed quite mature in the past 60 years, and has made important contributions to the development of various aircraft, including M3 level combat/reconnaissance aircraft, supersonic cruise, stealth, short-range landing and super-mobility fighters. , subsonic vertical landing fighters, wide-body aircraft that meet the requirements of the 180-min dual-engine extended-line passenger aircraft (ETOPS), giant helicopters with a payload of 20 tons, and tilt-rotor aircraft with a speed of more than 600 km/h. At the same time, it also laid the foundation for a variety of aviation modified light ground gas turbines.

Third, look to the future

The characteristics of engine research and development work are technically difficult, costly, and long-term. The engine has a decisive influence on the performance of the aircraft and the success and progress of the aircraft development, and the engine technology has good dual-use characteristics for the national defense and nationals. The economy is important. Therefore, several countries in the world that can independently develop advanced aero engines will give priority to the development of aero-engines as a national policy, classify engine technology as a key technology for the country and national defense, and give a large amount of investment to ensure that the engine is relatively independent and leading, and strictly prohibited. Export of key technologies. Some aero-engine start-up industrial countries have also developed major technological development plans, trying to establish the ability to independently develop or participate in international cooperation to develop advanced aero engines. In order to meet the requirements of various aircraft developments in the 21st century, aviation developed countries have implemented a new turbine engine technology development plan since the late 1980s. The goal is to master the technology that doubles the engine capacity from 2005 to 2008. The results achieved have been successfully applied to the improvement of some in-service engines and the development of new models, and are currently in the verification phase of the final goal. In view of the successful implementation of the plan and the important role of the engine in aviation development, some countries have developed further engine technology development plans. The new plan will continue to increase its capacity while placing greater emphasis on cost reduction. The goal is to increase the economic affordability measured by the ratio of engine capacity (push-to-weight ratio/fuel consumption rate) to full-life cost from 2006 to 2015. Times. In the field of hypersonic propulsion, the focus is on the development of supersonic combustion ramjet engines and pulse detonation wave engines. The near-term goal is to realize the missile propulsion system of M 4-8. The long-term goal is to develop maneuvering aircraft for hypersonic speeds, trans-atmosphere aircraft and low-cost A reusable combined power system for a round-trip transportation system between the world. Other new concept engines and new energy engines are also being explored, such as micro-electromechanical-based micro-UAV ultra-micro turbine engines and multi-electric engines, as well as liquid hydrogen fuel, fuel cells, solar and microwave energy, etc. New energy power.

1. Comprehensive high performance turbine engine technology plan

In 1988, the US Air Force first initiated the development and implementation of the High Performance Turbine Engine Technology (IHPTET) program, which was involved in the Air Force, Navy, Army, Department of Defense Pre-Research, NASA, and seven major engine manufacturers. The overall goal of the plan is to double the capacity of the aviation propulsion system by 2005, that is, the thrust-to-weight ratio or power-to-weight ratio is increased by 100% to 120%, and the fuel consumption rate is reduced by 15% to 30%. In other words, it takes 15 to 20 years to achieve the achievements of the past 30 to 40 years, and the production and maintenance costs are reduced by 35% to 60%. It can be said that aviation propulsion technology is showing an accelerated development trend.

In Europe, mainly in the UK, Italy and Germany participated in the second phase of the advanced core military engine program (ACME-II), and the United Kingdom and France jointly implemented the Advanced Military Engine Technology (AMET) program. The goal of ACME-II is to verify technologies with a weight-to-weight ratio of 18 to 20, a 15% to 30% reduction in fuel consumption, a 30% lower manufacturing cost, and a 25% lower life cycle cost from 2005 to 2008. Russia has a similar plan, the goal is to verify the technology in 2010~2015, compared with the fifth-generation engine in Russia, the weight is reduced by 30~50%, the fuel consumption rate is reduced by 15~30%, and the reliability is increased by 60%~ 80%, the maintenance workload is reduced by 50% to 65%.

This section highlights the US IHPTET program, which takes a revolutionary approach to technology that combines breakthroughs in engine aerodynamics, materials, structural design, and control to dramatically increase turbine front temperature, simplify structure, reduce weight, and achieve optimal performance. Control, and finally reach the intended goal. The total planned investment is 5 billion US dollars. It is divided into three phases in the 1995, 2000 and 2005 fiscal years, reaching 30%, 60% and 100% of the total target respectively. At present, the second phase of the task has been completed, the third phase of the plan is being implemented, and has entered the core machine's verification machine test phase. The following will illustrate the progress of the turbojet/ turbofan engine technology.

● The first phase of the military selected Pratt Whitney as the main contractor and General Electric as the alternative contractor. Represented by Pratt & Whitney's XTE65/2 verification machine, the target of the first phase has been reached and exceeded in the September 1994 trial - the thrust-to-weight ratio increased by 30%, and the turbine inlet temperature is higher than the existing The advanced engine is 222°C higher than the target 55°C. The main new technologies verified on it are: small aspect ratio sweeping fan, Alloy C flame retardant titanium alloy compressor material, double alloy compressor disk, brush seal, ceramic composite flame tube floating wall, "super cold" Turbine blade and spherical convergence adjustment plate vector nozzle (SCFN, original phase 2 target).

● The second phase of the military selected General Electric Company / Allison Pre-Research Joint Group as the main contractor, Pratt & Whitney as the alternative contractor to ensure that a contractor fails, the technology can still get development of. At the end of 1991 and June 1994, Allison Pre-Research Company tested the XTC16/1A and XTC16/1B core machines for the second phase of the IHPTET program, and reached the second-phase core machine goal four years ahead of schedule. The new technologies verified on these two core machines are: compressor overall leaf ring structure, Lamilloy "cast cold" turbine blades, turbine integral blade disk, γ titanium aluminum alloy with temperature resistance of 700~800 °C, circumferential staged combustion Room and ceramic bearings.

The joint team of General Electric Company/Ellison Pre-Research Company tested a cooperative variable cycle core machine XTC76/2 from 1995 to 1996. The core machine has a 5-stage compressor and a 1-stage turbine. In 1998, the variable cycle verification machine based on the XTC76/2 core machine was tested. The new technology used on the verification machine includes: advanced 2-stage curved sweep fan, stepless guide vane counter-rotating turbine, metal base. Composite low pressure turbine shaft and nickel aluminum alloy turbine components.

In 1999, Puhui also tested the initial prototype of the next-generation fighter engine PW7000. XTE-66, which belongs to the second-stage technical verification machine, will increase the thrust-to-weight ratio by 50% to 15~16. The second stage of the IHPTET plan variable cycle engine can achieve the unit thrust of F100-229 and F110-129 with no force, which has the following improvements compared with F100-229: the number of rotor stages is reduced by 5~ Level 6; length reduced by 40%; thrust-to-weight ratio increased from 8 to 16;

The typical task fuel consumption is reduced by 1/3; the cost is reduced by 20%~30%; the stealth ability is improved.

● The third phase of the third phase has passed the application basic research and component research phase, and has achieved phased results in aerodynamics, structure and materials. In 2001 and 2002, it entered the core machine and verification machine verification respectively. The technologies to be verified are: a variable-cycle engine with a core-driven fan stage, a single-stage split-blade fan with a pressure ratio equivalent to a Class 3 fan of the F100-200 engine, and a high-pressure gas-pressure of a metal-based composite integral leaf ring structure of an advanced pressure ratio. Machine (4 stages to achieve the pressure ratio of F100 engine 10), titanium aluminum compressor rotor and stator blades, stationary vortex stabilized combustion chamber, combustion chamber active temperature field control, ceramic matrix composite flame tube, ceramic matrix composite turbine guide vane Counter-rotating low-pressure turbine without guide vanes, double-spoke turbine discs, swirling afterburner, fluid control vector nozzles (reducing weight and cost by 60% and 25%, respectively), magnetic bearings, film bearing, Built-in integral starter/generator and model-based distributed active stability control system.

Since the implementation of the IHPTET program, its results have been applied to the development of new models for many military and civilian engines and improvements to existing models. In terms of civilian engines, there are GE90, PW4084, CFM56-7, AE3007 and FJ44. In military engines, there are F117, F118, F119, F135, F136, F404, F414, F100 and F110.

2. General, economically affordable advanced turbine engine program

Due to the important role of the IHPTET program in achieving air superiority and commercial competitive advantage and the great success that has been achieved, the United States is preparing to implement the IHPTET plan's successor plan, the VAATE program, starting in 2006. The guiding ideology is to improve performance while improving Emphasis on reducing costs. The overall goal of VAATE is that the level of technology achieved in 2017 will increase the affordability to 10 times that of the F119 engine. Technical verification will be carried out in two phases. From the first phase to 2010, the economic affordability will be increased by a factor of six; the second phase will increase the affordability to 10 times by 2017.

The economic affordability of a propulsion system is defined as the ratio of capacity to life-time cost, where capacity is a function of the thrust-to-weight ratio and the intermediate state fuel consumption.

The VAATE program serves not only the engines of manned aircraft, but also the engines of drones as well as marine and surface gas turbines. Like the IHPTET program, the VAATE program is still hosted by the Department of Defense, with NASA, the Department of Energy, and six engine manufacturers. The level of investment is also comparable to the IHPTET program, which is more than $300 million a year and is shared equally by the government and engine manufacturers. The VAATE program will be implemented through the interaction of three key research areas.

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