fuel is nontoxic and pollution-free. The non-coaxial two-turbine pneumatic series
structure is adopted in the structure. The helical tube bundle type hydrogen emission cooling and large nozzle with an area ratio of 80:1 are adopted in the nozzle,
which effectively improves the performance and reliability of the engine. The cold
helium heating and pressurization system use the tank pressurization system to
ensure that the inlet of the engine pump has a certain pressure, so that the liquid
propellant is continuously supplied to the engine. Using advanced cold helium
pressurization technology, the cylinder with high-pressure helium is installed in the
liquid hydrogen tank. After liquid hydrogen filling, the cylinder is immersed in
liquid hydrogen, and the helium in the cylinder is cooled to the liquid hydrogen
temperature (20.3 K). When the engine is working, the cold helium gas is heated
through the cold helium heater to the liquid oxygen temperature and then introduced into the liquid oxygen tank for pressurization. The hydrogen energy pneumatic servo mechanism uses the hydrogen pneumatic engine as its energy source.
The hydrogen flows from the engine combustion chamber head through the flow
limiting tube, and blow the pneumatic blade through a one-way valve, thus driving
the hydraulic pump and the two-way swing servo mechanism to achieve three-stage
flight attitude control. The servo mechanism uses low-temperature hydrogen as
medium and adopts low-temperature hydrogen aero-engine technology with high
power–mass ratio. In addition, the autopilot rudder of air defense missile often uses
gas rudder. For example, the Soviet S-300 missile initially used gas steering gear;
the American Sparrow missile series used solid gas generator to drive gas–liquid
accumulator seeker energy and nitrogen to drive gas–liquid accumulator pilot; the
British sea javelin ship-to-air missile used gas motor-driven hydraulic steering gear;
the Italian Aspide Army general air defense missile used gas turbopump
electro-hydraulic energy pilot. The nitrogen cylinder pressure of the air-conditioned
actuator of an aircraft is over 65 MPa. The multistage decompression control
schemes of pressure 10 and 2.5 MPa are adopted to control gas pressurization and
ultrahigh pressure so as to solve the problems of gas storage and transmissionation.
Japan is studying passenger aircraft powered by liquid hydrogen and biofuels. In
order to prevent the residual gas from mixing into the original system, vacuum
filling method is adopted when the hydraulic or pneumatic actuator in the control
cabin of missile and rocket is filled with working medium. The high temperature
and high-pressure gas pressure used by the aircraft are about 5 MPa and the temperature is 1200 °C. The nitrogen gas storage cylinder pressure of the cold air
steering gear is over 65 MPa. A series of key technological breakthroughs have
been made in gas pressurization and ultrahigh pressure control technology by
adopting two-stage decompression control scheme with pressure of 10 and 2.5 MPa
and flow rate of 50 L/min.
Hydrogen can be safely stored and transmissioned at ground atmospheric
pressure. Space scientists are studying the key technologies of hydrogen storage
vessels, control devices and thrusters in the near space and space extreme environment, including the performance of various special pneumatic control valves in
the extreme environment, hydrogen storage materials, gas filling and releasing rules
and hydrogen aerodynamic thrusters.
13.1 Pneumatic System and Fuel Cell Hydrogen Transmission System
325
structure is adopted in the structure. The helical tube bundle type hydrogen emission cooling and large nozzle with an area ratio of 80:1 are adopted in the nozzle,
which effectively improves the performance and reliability of the engine. The cold
helium heating and pressurization system use the tank pressurization system to
ensure that the inlet of the engine pump has a certain pressure, so that the liquid
propellant is continuously supplied to the engine. Using advanced cold helium
pressurization technology, the cylinder with high-pressure helium is installed in the
liquid hydrogen tank. After liquid hydrogen filling, the cylinder is immersed in
liquid hydrogen, and the helium in the cylinder is cooled to the liquid hydrogen
temperature (20.3 K). When the engine is working, the cold helium gas is heated
through the cold helium heater to the liquid oxygen temperature and then introduced into the liquid oxygen tank for pressurization. The hydrogen energy pneumatic servo mechanism uses the hydrogen pneumatic engine as its energy source.
The hydrogen flows from the engine combustion chamber head through the flow
limiting tube, and blow the pneumatic blade through a one-way valve, thus driving
the hydraulic pump and the two-way swing servo mechanism to achieve three-stage
flight attitude control. The servo mechanism uses low-temperature hydrogen as
medium and adopts low-temperature hydrogen aero-engine technology with high
power–mass ratio. In addition, the autopilot rudder of air defense missile often uses
gas rudder. For example, the Soviet S-300 missile initially used gas steering gear;
the American Sparrow missile series used solid gas generator to drive gas–liquid
accumulator seeker energy and nitrogen to drive gas–liquid accumulator pilot; the
British sea javelin ship-to-air missile used gas motor-driven hydraulic steering gear;
the Italian Aspide Army general air defense missile used gas turbopump
electro-hydraulic energy pilot. The nitrogen cylinder pressure of the air-conditioned
actuator of an aircraft is over 65 MPa. The multistage decompression control
schemes of pressure 10 and 2.5 MPa are adopted to control gas pressurization and
ultrahigh pressure so as to solve the problems of gas storage and transmissionation.
Japan is studying passenger aircraft powered by liquid hydrogen and biofuels. In
order to prevent the residual gas from mixing into the original system, vacuum
filling method is adopted when the hydraulic or pneumatic actuator in the control
cabin of missile and rocket is filled with working medium. The high temperature
and high-pressure gas pressure used by the aircraft are about 5 MPa and the temperature is 1200 °C. The nitrogen gas storage cylinder pressure of the cold air
steering gear is over 65 MPa. A series of key technological breakthroughs have
been made in gas pressurization and ultrahigh pressure control technology by
adopting two-stage decompression control scheme with pressure of 10 and 2.5 MPa
and flow rate of 50 L/min.
Hydrogen can be safely stored and transmissioned at ground atmospheric
pressure. Space scientists are studying the key technologies of hydrogen storage
vessels, control devices and thrusters in the near space and space extreme environment, including the performance of various special pneumatic control valves in
the extreme environment, hydrogen storage materials, gas filling and releasing rules
and hydrogen aerodynamic thrusters.
13.1 Pneumatic System and Fuel Cell Hydrogen Transmission System
325