JP2934494B2 - Collectible spacecraft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a recovery type spacecraft having a brake plate using an air braking force.

[Related Art] Various types of recoverable spacecraft have been proposed as shown in FIG.

However, other than the Apollo-type capsule and the blunted capsule have not been put to practical use.

[Problems to be Solved by the Invention] (1) To improve environmental conditions such as acceleration during recovery.

In FIG. 5, "severe" is about 10 to 15G.

 It can be used for manned use if it can be reduced to about 3-5G.

Also, the structural design that withstands 15G and the structural design that withstands 5G are naturally different.

The best way to reduce the acceleration (inverse G) is to increase the projected area in the rush direction with respect to the weight of the recovery machine (capsule).

In general, when an object in a high altitude is lowered to the ground using atmospheric braking, it is necessary to convert the potential energy of the object in a high altitude into heat by atmospheric braking and to reduce the speed to a speed at which the object can be decelerated by a parachute or the like.

This means that the total deceleration amount is constant.

If the projected area with respect to the weight is small, the falling by the air is small because the drag by the atmosphere is small. This means that the main deceleration must be performed when falling at relatively high altitudes with high atmospheric density at high and high speeds.

Conversely, if the projection area is large, the time for slowing down and deceleration becomes longer, so that the deceleration rate per time may be small.

Apollo-type capsules and blunt-type capsules cannot increase the ratio of the projected area in the rush direction to the weight of the recovery machine, so it is necessary to increase the deceleration rate per hour by the atmosphere during recovery, that is, the reverse acceleration (reverse G). is there.

However, if the inverse G is large, it is necessary to make the structure to withstand that, and the cost is high.

Also, in the case of experiments performed in orbit such as bio experiments,
In some cases, it may not be possible to design the test equipment to withstand 10-15G.

(2) To improve thermal environmental conditions.

Since the Mach number at the time of re-entry into the atmosphere will be 20 to 30 or more,
The surface is subjected to strong aerodynamic heating.

When the outer surface is formed using ordinary metal, the temperature rises to 2000 ° C or higher due to aerodynamic heating and melts. Therefore, measures such as abrasive cooling or heat-resistant ceramic tiles are taken.

The countermeasure for aerodynamic heating mitigation may be to drop slowly and fluffy, and the countermeasure is the same as that of (1).

However, since both ablative coolant and ceramic tile are generally rigid, the idea of inflating with gas pressure as in the case of a balut capsule is not feasible.

In addition, it is technically difficult to install a deployable air brake plate in an area where aerodynamic heating is severe, because it is exposed to a high-temperature atmosphere.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a recovery machine which solves the above-mentioned problems and is effective in reducing the level of inverted G of a blunt capsule.

[Means for Solving the Problems] A recovery type spacecraft according to the present invention is a spacecraft which reenters the atmosphere and can be recovered in the air, at sea, or on the ground. It is equipped with a deployable control plate for increasing power.

[Operation] The deployable brake plate mounted downstream of the temperature boundary layer is in a housed state when the capsule is mounted on a fairing or the like of a rocket.

Before the re-entry into the atmosphere, this control plate is deployed to increase the projected area in the entry direction and reduce the level of the inverse G as compared to a state where it is not deployed.

Embodiment An embodiment of the present invention is shown in FIG. 1 to FIG.

FIG. 1 is a view showing a state in which a deployable atmospheric brake plate is accommodated in an embodiment of an ablative cooling downstream position deployable recovery machine.

In this state, it is mounted on a rocket or the like as shown in FIG.

In FIG. 1, reference numeral 1 denotes an outer structure portion of a blunt type carbur cell, and reference numeral 2 denotes a deployable atmospheric braking plate (in a housed state).

FIG. 2 is a view showing a state in which the atmospheric brake plate has been deployed before reentering the atmosphere.

In FIG. 2, reference numeral 1 denotes an outer structure of a blunt capsule having an ablative cooling section on its surface.

 Reference numeral 2 denotes an expansion-type atmospheric braking plate (deployed state), 3 denotes an extension-type outer edge holding mechanism, and 4 denotes a connecting portion of the atmospheric braking plate to a main body.

 FIG. 3 is a sectional view of an embodiment according to the present invention.

The surface of the outer structure 1 is provided with an ablative cooling unit 11, and the atmospheric brake plate 2 is supported by a recovery machine by a hinge 21 and is opened and closed by an actuator (for example, a pneumatic actuator) 22.

The atmospheric braking plate 2 has a structure in which an ablative coolant is bonded to the surface of an aluminum or titanium honeycomb plate.

Ablative cooling is a method that utilizes an endothermic reaction of thermal decomposition, and emits gas at a relatively low temperature.

Therefore, the downstream portion is slightly eased thermally. Roughly speaking, if the ratio of projected cross-sectional area / weight is the same, it can be said that the thermal environment is substantially the same.

The degree to which the atmospheric brake plate located downstream of the ablative cooling unit becomes thermally severe when there is no ablative cooling effect is determined by the design of the ablative cooling unit.

If a large amount of relatively low-temperature pyrolysis gas is generated by ablative cooling, the thermal severity can be reduced to less than 1/2.

As described above, in the recovery type spacecraft according to the present invention, the deployable air brake plate is provided downstream of the temperature boundary layer by ablative cooling of the blunt capsule, and the projected area in the rush direction with respect to the capsule mass is enlarged.

This makes it possible to reduce the degree of the reverse G at the time of re-entry into the atmosphere, and also to control the re-entry trajectory by controlling the brake plate.

Unlike the bulk portion of the bulk capsule in FIG. 5, the brake plate downstream of this temperature boundary layer is located downstream of the temperature boundary layer employing the cooling method of ablative cooling, so that its thermal protection is also simple. Is possible.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

(1) Recovering can be performed in a state where the level of reverse G at the time of re-entry into the atmosphere, which is a drawback of a blunt capsule, is reduced.

(2) Since the mounting position of the atmospheric brake plate is located downstream of the temperature boundary layer for wall cooling, thermal protection of the brake plate is facilitated.

(3) By controlling the deployment angle of the brake plate, the flight path of the collection capsule in the atmosphere can be controlled.

[Brief description of the drawings]

FIG. 1 is a view showing a state in which an atmospheric brake plate of a deployable recovery machine of the present invention is housed, FIG. 2 is a view showing a state in which an atmospheric brake plate of the deployable recovery machine of the present invention is deployed, and FIG. FIG. 4 is a sectional view of an embodiment according to the present invention, FIG. 4 is a diagram showing a state in which the embodiment according to the present invention is mounted in a rocket fairing, and FIG. 5 is a diagram showing a conventional recovery spacecraft. (Explanation of reference numerals) 1... Outer structural portion of blunt capsule 2... Atmospheric brake plate 3... Extendable outer edge holding mechanism 4.

────────────────────────────────────────────────── (5) References JP-A-54-113124 (JP, A) US Patent 3062148 (US, A) US Patent 3,113,750 (US, A) US Patent 3,128,964 (US, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) B64G 1/62

Claims (1)

(57) [Claims] A spacecraft which reenters the atmosphere and can be recovered in the air, at sea, or on the ground, is provided with an expandable control plate for increasing air braking force in a region downstream of a temperature boundary layer by ablative cooling. A recoverable spacecraft characterized in that: