Flow rate control device with compliant structure

A hydraulic-pneumatic system including a flow rate control device formed inside a pipe through which a fluid flows, injecting a propellant inside a propellant tank by a pressure in a pressurization gas tank, wherein the flow rate control device comprises:

• a main plate formed inside the pipe so as to face a fluid flow direction and including a through hole formed at the center thereof, the through hole having a perimeter;
• a sub-plate disposed in front of the through hole of the main plate, the sub-plate having a circumference, and corresponding to the size of the through hole;
• and
• a cylindrical column connecting the perimeter of the through hole and the circumference of the sub-plate to each other, the column having a length from the through hole to the sub-plate, the column including a side surface and a plurality of holes in the side surface for discharging the fluid through the column, the plurality of holes being formed in a circular shape or a polygonal shape, and wherein the plurality of holes are configured to be expanded and contracted by a pressure applied to the sub-plate,
• wherein the sub-plate is displaced by inflowing fluid, and wherein the column has a compliant structure such that the length of the column decreases as the sub-plate is displaced by the inflowing fluid,
• wherein the flow rate control device further comprises:
• a first flow path connecting the pressurization gas tank and the propellant tank to each other;
• and a second flow path connecting the propellant tank and an engine or a ground facility tank to each other, wherein the flow rate control device is provided in the first flow path, such that a pressurization gas of the pressurization gas tank constantly pressurizes the propellant, and wherein the flow rate control device is provided in the second flow path to inject a constant flow rate of the propellant regardless of an influence of the engine, and
• wherein a plurality of holes are formed in the sub-plate for balancing the sub-plate and preventing the sub-plate from being biased toward one side.