Technology of Rocket

Transcription

1 Technology of Rocket

2 Parts of Rocket There are four major parts of rocket Structural system Propulsion system Guidance system Payload system

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4 Structural system The structural system of a rocket includes all of the parts which make up the frame of the rocket; the cylindrical body, the fairings, and any control fins. The function of the structural system is to transmit the loads from the forces generated during the flight and to provide low aerodynamic drag for flight through the atmosphere.

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6 Forces are vector quantities having both a magnitude and a direction. In flight, a rocket is subjected to four forces; weight, thrust, and the aerodynamic forces, lift and drag.

7 A model rocket is a combination of many parts; the nose cone, payload, recovery system, body tube, engine, and fins. Each part has a weight associated with it which you can estimate, or calculate, using Newton's weight equation: w = m * g

8 Thrust is the force which moves the rocket through the air, and through space. Thrust is generated by the propulsion system of the rocket through the application of Newton's third law of motion; For every action there is an equal and opposite re-action. The thrust equation shown above works for both liquid rocket and solid rocket.

9 The amount of thrust produced by the rocket depends on the mass flow rate through the engine, the exit velocity of the exhaust, and the pressure at the nozzle exit. All of these variables depend on the design of the nozzle. The smallest cross-sectional area of the nozzle is called the throat of the nozzle.

10 The hot exhaust flow is choked at the throat, which means that the Mach number is equal to 1.0 in the throat and the mass flow rate m dot is determined by the throat area. The area ratio from the throat to the exit Ae sets the exit velocity Ve and the exit pressure pe.

11 Subsonic-These conditions occur for Mach numbers less than one, M < 1. For the lowest subsonic conditions, compressibility can be ignored. Transonic-As the speed of the rocket approaches the speed of sound, the flight Mach number is nearly equal to one, M = 1, and the flow is said to be transonic. Supersonic These conditions occur for Mach numbers greater than one 1 < M< 5. Hypersonic-For speeds greater than five times the speed of sound, M > 5, the flow is said to be hypersonic.

12 Aerodynamic forces are generated and act on a rocket as it flies through the air. The magnitude of the aerodynamic forces depends on the shape, size and velocity of the rocket and some properties of the air through which it flies. Aerodynamic forces are not generated by a force field, in the sense of the gravitational field,or an electromagnetic field. The single aerodynamic force is broken into two components: the drag force which is opposed to the direction of motion, and the lift force which act perpendicular to the direction of motion.

13 Propulsion system Fins- Stabilizes rocket during flight. Without fins, the rocket would wobble in flight and would land in an unpredicted spot. Nozzle-The function of the nozzle is to direct the hot exhaust gases out the back of the engine. Fuel- It is divided in to three types 1.Solid type fuel 2.Liquid type fuel 3.Hybrid type fuel

14 Solid type fuel Solid type fuel Rocket-Gun powder is used and it is a mixture of Sulphur,Charcoal and Potassium nitrate. The gun powder is also called as black powder Gun powder was invented and documented and used in ancient china but Now modern firearms does nt use gun powder instead of that smokeless powder was used.

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16 Liquid type fuel Liquid fuel rocket-liquid rocket with an engine that uses propellants in liquid form. Liquid rockets have been built as monopropellant rocket using a single type of propellant, bipropellant rockets using two types of propellant. Liquid propellant are liquid oxygen and liquid hydrogen.

17 A liquid-propellant rocket carries fuel and an oxidizer in separate tanks. The fuel circulates through the engine's cooling jacket before entering the combustion chamber. This circulation preheats the fuel for combustion and helps cool the rocket.

18 Hybrid type fuel Hybrid rocket uses two types of propellants i.e. one in solid propellant and the other is either gas or liquid propellant. Hybrid rockets exhibit advantages over both liquid rockets and solid rockets especially in terms of simplicity, safety, and cost. The specific impulse (I sp ) performance of hybrids is generally higher than solids and roughly equivalent to hydrocarbon-based liquids.

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21 Guidance system The guidance system of a rocket includes very sophisticated sensors, on-board computers, radars, and communication equipment. The guidance system has two main roles during the launch of a rocket; to provide stability for the rocket, and to control the rocket during maneuvers.

22 The motion of any object in flight is a combination of the translation of the center of gravity and the rotation of the object about its center of gravity. Many different methods have been developed to control rockets in flight.

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24 An orthogonal coordinate system has each of its coordinate directions perpendicular to all other coordinate directions. Initially, our rocket is at point "0", with coordinates x0, y0, and z0 at time t0. In general, the rocket moves through the domain until at some later time t1 the rocket is at point "1" with coordinates x1, y1, and z1. We can specify the displacement - d in each coordinate direction by the difference in coordinate from point "0" to point "1". The x- displacement equals (x1 - x0), the y-displacement equals (y1 - y0), and the z-displacement equals (z1 - z0). d = y1 - y0 The velocity -V of the rocket through the domain is the derivative of the displacement with respect to time. In the Y - direction, the average velocity is the displacement divided by the time interval: V = (y1 - y0) / (t1 - t0)

25 As a rocket flies through the air, it both translates and rotates. The rotation occurs about a point called the center of gravity. The center of gravity is the average location of the weight of the rocket.

26 All of the control methods produce a torque about the rocket's center of gravity which causes the rocket to rotate in flight.

27 where V is the velocity for a circular orbit, g0 is the surface gravitational constant of the Earth (32.2 ft/sec^2), Re is the mean Earth radius (3963 miles), and h is the height of the orbit in miles.

28 Payload is the net carrying capacity of an aircraft or spacecraft warhead refers to the explosive material and detonator that is delivered by a missile, rocket, or torpedo

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