DynamicRC - 자유게시판

하하...... 아래 사이트에서 긁어 왔습니다. 일단 용어정리부터 하자고요.

http://www.autogyro.com/technic/terms.htm

ADVANCING BLADE - The portion of the rotor disk in which the rotation of the blade is moving in the direction of the aircraft`s travel (into the relative airstream).

AFT ROTOR TILT - The number of degrees the rotor disk is tilted aft in reference to the longitudinal reference line thru the model. : Generally this is referring to the neutral (zero trim) position of the disk...

AIRFOIL - A surface designed to produce lift from the movement of air over it. Ideally it should present the greatest amount of lift with the least amount of drag.

AUTOGYRO - A heavier-than-air flying machine which derives its lift from a rotor system mounted above the machine, with the blades rotating more or less horizontally.

AUTOROTATION - Aerodynamic rotor operation. A flight condition made possible by the vertical or horizontal movement of air through the rotor system. For the models, when the rotor fully accelerates on its own, it is said to be autorotating.

BLADE BALANCE - Rotor blades that are equal in weight will balance each other. Unbalanced (unequal in weight) rotor blades will cause model shake and instability in flight.

BLADE CAMBER - Measure of the blade thickness.

BLADE CHORD - Width of the rotor blades.

BLADE INCIDENCE (Blade Pitch) - The blade angle of attack in reference to the rotor disk plane, or the angle from zero lift line to the plane of disk rotation.

CW - Clockwise rotation of the rotor when viewed from above.

CCW - Counter-clockwise rotation of the rotor when viewed from above.

CENTER OF GRAVITY (CG) - The point where the resultant of all weight forces will hang evenly from this point. Usually, on a model, this point is just forward of the main mast.

CENTER OF PRESSURE - An imaginary point on the chord line of all the rotor blades where all the aerodynamic forces of the airfoil surfaces are concentrated.

CENTRIFUGAL FORCE - Horizontal rotational outward force.

CHORDLINE - A straight line between the exact center of the leading edge and the trailing edge of of the rotor blade.

CHORDWISE BALANCE - A point at the center of lift of the blade, along the chord line. On a model it is advisable that the blade be balanced at this point as well as along the span.

COMPRESSIBILITY - Forces acting on a rotor blade when its tip speed approaches the speed of sound.

CONING - Upturned blade due to combined lift and centrifugal force.

CONING ANGLE - The angle of the rotor blade to the plane of disk rotation, formed when the rotor blades are lifting the model.

DISK (or DISC) - The area swept by the blades of the rotor.

DISK LOADING - The gross weight of the model divided by the rotor disk area. The greater the disk loading, the higher sink rate and the steeper the glide angle.

DISSYMMETRY OF LIFT - The unequal lift across the rotor disk caused from the advancing blade creating more lift than the retreating blade.

DOWNTHRUST - The downward angle of the engine thrust line in reference to the longitudinal reference line through the fuselage. Used primarily to counter rotor drag.

DROOP - Downward bending of the blades at rest, due to gravity.

DYNAMIC ROLL OVER - A roll over caused by violent rotor blade flapping. This can be caused by low rotor RPM combined with excessive ground speed.

FLAPPING - The up-down motion of the rotor blade on its center hinge. Without at least a small amount of flapping, an autogyro would roll over on its side during flight due to unequal lift between the advancing and retreating rotor blades.

FLAPPING HINGE - Hinging which allows the blades freedom to flap up or down.

FLAPPING LIMITS - The amount (generally in degrees) that the rotor blades are permitted to flap up-down in flight.

FLUTTER - A self induced oscillating motion of improperly designed or balanced rotor blades.

GROUND EFFECT - A beneficial increase in lift near the ground. Readily apparent when the rotor height is one-half of the rotor`s diameter over the ground. Less power engine power required due to the air being thrust downward to meet the ground. This denser air is partially trapped beneath the rotor disk.

GROUND VORTEX - The horizontal whirlwind that forms at the forward edge of the rotor wake when the autogyro flies at low speeds close to the ground.

GYROPLANE - An aircraft whose lift is developed by the rotor blade system using the principles of autorotation. GYROPLANE is also the official FAA designation for the full sized aircraft.

HANG ANGLE - The angular difference between the longitudinal reference line thru the fuselage center and the level horizon when the model is suspended by the rotor center.

HANGLE - Hoosier for Hang Angle...

HORSEPOWER LOADING - The ratio of gross wieght to horsepower, obtained by dividing the total weight by the engine`s horsepower rating.

INDUCED DRAG - Drag produced in the process of of producing lift.

INDUCED VELOCITY - The downward air velocity generated in the process of developing rotor thrust.

LEAD-LAG - The rotor blade tip movement needed to adjust the rotor blade(s) to get the weight of the whole rotor exactly equal in all directions from the rotor shaft.

LIFT - Vertical force required to sustain level flight.

L / D RATIO - Coefficient of lift divided by coefficient of drag.

MAST - The main vertical structural member of the model connecting the rotor assembly to the airframe.

PARASITIC DRAG - Drag produced by non-lifting structures.

POWER LOADING - Gross weight divided by engine horsepower.

RADIUS OF GYRATION - Radius of effective CG of blade during rotation.

RELATIVE WIND- the velocity and direction of the air flowing toward the airfoil/wing/etc that is not influenced by the airfoil etc. We call that V(infinity) in aero terms. I would like to be able to write a capital V with a sideways "8" for infinity because that is standard but I'll abbreviate here with Vi. For a whole aircraft it is the opposite from the direction the aircraft is flying in ( not where the propellor points but the direction that the center of gravity is moving).

REFLEX BEVEL - Rotor blade trailing edge bevel (upturn) used to control pitching of the blade.

RETREATING BLADE - The blade going away from the relative airstream.

ROTOR DIAMETER - Diameter of the rotor disk.

ROTOR UNLOADING - Reducing the rotor lift using supplemental wings.

SOLIDITY RATIO - Total blade area divided by the disk area.

TIP SPEED RATIO - Airspeed / tip speed figure of merit.

TIP WEIGHTS - Small weight(s) installed in the rotor blades near the tips.

TRACKING - Blade tips following the same path during rotation.

WINDMILLING - Rotor operation non-aerodynamically assisted.