Electron beam ablation propulsion method and system

[0017] Example one

[0018] As shown in FIG. 1, the electron beam ablation propulsion system of this embodiment includes: an electron beam generating device 101 and a target 102.

[0019] The electron beam generating device 101 generates an electron beam, and the electron beam is directed toward the target 102 through the exit of the electron beam generating device 101 to generate ablation recoil thrust along the electron beam transmission direction. The target material 102 receives the electron beam generated by the electron beam generating device 101, and generates gas or fine particles outward (opposite to the electron beam transmission direction) under the ablation of the electron beam. The material of the target 102 may be gold, silver, copper, aluminum, etc., and the present invention is not limited thereto.

[0020] The electron beam ablation propulsion system of this embodiment can also be as Figure 1B As shown, Figure 1B versus Figure 1A The difference is that the target is not placed in the vacuum chamber.

[0021] The electron beam is incident on the surface of the target material, interacts with the target material, and its energy is fully coupled into the target material, causing it to undergo a series of thermodynamic effects, causing melting and vaporization, and ejecting gas or tiny material particles outward to form Recoil, generate thrust. Adjusting the pulse width, frequency, peak power density, etc. of the beam source can realize the adjustment of micro-propulsion performance.

[0022] The advantage of using the electron beam generator 101 as the beam source is that the response time of the interaction between the electron beam and the target is fast; the ablation beam spot is small, the action area is accurate, and it is convenient for precise positioning of the advancement; the controllability of the electron beam is good, Adjusting the pulse width, frequency, peak power density, etc. of the electron beam generating device 101 can complete the control of the propulsion performance; it is not affected by the reflection performance of the target material, and can be used to ablate difficult metals such as gold, silver, copper, and aluminum. With materials ablated by laser.

[0023] The electron beam generator 101 can be a short pulse high current electron beam generator, including: Marx generator-pulse forming line-multi-stage discharge chamber, trigger-single-stage discharge chamber, pseudo-spark discharge device, etc. The present invention only uses pseudo-spark The spark discharge device will be described in detail as an example.

[0024] Such as figure 2 As shown, the pseudo-spark discharge device includes: high-voltage power supply (including: voltage regulator 201, step-up transformer 202, and voltage doubler circuit 203), discharge capacitor 204 and pseudo-spark discharge chamber 205, high-voltage power supply, discharge capacitor 204 and pseudo-spark discharge The chambers 205 are electrically connected in sequence, and the discharge capacitor 204 is connected in parallel with the pseudo-spark discharge chamber 205.

[0025] The pseudo-spark discharge device also includes: a charging resistor R, an intake valve 206, a vacuum pump connection port 207, a target 208, and a vacuum chamber 209. The charging resistor R is connected between the discharge point capacitor 204 and the voltage doubler circuit 203. Preferably, the size of the charging resistor R is 150 MΩ, and the present invention is not limited to this. The vacuum pump connection port 207 is connected to the vacuum pump and is used to vacuum the vacuum chamber 209.

[0026] The pseudo-spark discharge chamber 205 is used to generate pulsed electron beams, such as image 3 As shown, the pseudo-spark discharge chamber 205 includes a metal electrode ring 301 and an insulating sheet ring 302. A plurality of metal electrode rings 301 and the insulating sheet ring 302 are bonded alternately at intervals. A central through hole 303 is formed in the middle of the pseudo-spark discharge chamber 205 as a transmission channel for the pulsed electron beam. The discharge cell maintains a high degree of axial symmetry and airtightness in order to generate a collimated electron beam and ensure a low pressure in the discharge cell.

[0027] Preferably, the number of the metal electrode ring 301 and the insulating sheet ring 302 in this embodiment can be 10 and 11, respectively, and the distance between the target and the beam exit of the pseudo-spark discharge chamber can be set to 1 cm. This is limited.

[0028] Preferably, the metal electrode ring 301 can be made of No. 45 carbon steel, and the insulating sheet ring 302 can be made of organic glass or ceramic. The geometric dimensions of the metal electrode ring 301 are: the outer diameter of the metal electrode ring is 22mm, the inner diameter is 1mm, and the thickness is 1mm; the geometric dimensions of the insulating sheet ring 302 are: the outer diameter of the insulating sheet ring is 37mm, and the inner diameter It is 11mm and the thickness is 2mm, and the present invention is not limited to this.

[0029] in figure 2 In the pseudo-spark discharge device shown, the size of the discharge capacitor 204 determines the size of the discharge frequency, and the discharge capacitor 204 can be 2245pF. At this time, the discharge frequency is about 1 Hz, and the present invention is not limited to this.

[0030] Pseudo-spark discharge occurs in the left half of the Bashen curve. The breakdown voltage decreases rapidly as the product of the air pressure and the discharge gap increases. The most notable feature is that the breakdown voltage rises rapidly as the air pressure drops. The working environment is low vacuum (1~100Pa). When the strong current pulsed electron beam generated by the pseudo-spark discharge is irradiated to the solid target, the energy will be exponentially decreased and deposited in the front surface of the target material in a microsecond or even nanosecond order, and it will be generated instantly High temperature and high pressure make the material produce great temperature gradient and pressure gradient. If the irradiation intensity of the electron beam is high enough, the front surface layer of the irradiated part of the target material can be ejected, thereby applying a recoil jet impulse to the target material to form a micropropulsion. The workflow of the electron beam ablation propulsion system is described in detail below:

[0031] First, a mechanical pump is used to evacuate the pseudo-spark discharge chamber 205 to a vacuum degree of 2 to 3 Pa. Then, the mains power is added to the voltage regulator 201, and the knob of the voltage regulator 201 is adjusted to adjust the size of the initial input voltage, thereby changing the output voltage applied to the pseudo spark discharge chamber 205. Through the step-up transformer 202, the mains voltage is raised to several tens of kilovolts. At this time, the output AC high voltage is adjusted to DC high voltage by the voltage doubler circuit 203, and the DC negative high voltage is added to the upper end of the pseudo-spark discharge chamber 205 through the charging resistor R. .

[0032] Then, air is taken in through the intake valve 206, and the air pressure of the pseudo spark discharge chamber 205 is slowly increased. When the air pressure reaches 7-10 Pa, the pseudo spark discharge chamber 205 starts to discharge stably. The generated intense pulsed electron beam interacts with the target 208, causing the surface material of the target 208 to be ejected outward, thereby generating a recoil thrust, pushing the target 208 forward to achieve the purpose of advancement. The magnitude of the recoil thrust is adjusted by adjusting the vacuum degree of the voltage regulator 201 and the pseudo-spark discharge chamber 205.

[0033] In this embodiment, the beam exit of the pseudo-spark discharge chamber 205 faces the target 102, and the target can be hung in the vacuum chamber 105 by filaments. Under the action of the recoil thrust generated by the electron beam ablation of the target 102 , The target 102 will be pushed to make a pendulum movement.

[0034] It can be seen from the above that the pseudo-spark discharge device has a simple structure, is convenient for miniaturization, and has a high beam current density that can generate an impulse of 10 -8 ~10 -8 The micro-thrust of the order of N·s meets the accuracy requirements of the relative position control of the micro-satellite; the ablation beam spot is small, which can realize the precise positioning of the micro-thruster; it works in a pulsed mode to realize a single injection of a small impulse; Adjusting the vacuum degree of the discharge chamber and the applied high voltage can complete the adjustment of the propulsion parameters; there are no problems such as plume pollution, leakage and heat dissipation.

[0035] The beneficial technical effects of the present invention are:

[0036] 1. The energy conversion efficiency is very high (80% to 90%). Under the same conditions, the impulse coupling coefficient of the interaction between the target and the short pulse high current electron beam is higher, so single element metals with high specific impulse performance can be used as The target material solves the problem that single-element metals with high specific impulse performance cannot be used due to the low impulse coupling coefficient in the laser ablation propulsion technology; 2. The pulse width is tens of nanoseconds, and the action time is extremely short, which can realize the single-element metal with a small impulse. 3, the response time of the interaction with the target material is fast; 4, the ablation beam spot is small, the action area is accurate, and the precise positioning is convenient for the advancement; 5, the controllable performance is good, by adjusting the pulse width, frequency, and frequency of the beam source Peak power density, etc., can complete the control of the propulsion performance; 6. It is not affected by the reflection performance of the target material, and can be used to ablate materials such as gold, silver, copper, aluminum and other difficult to ablate by laser; 7. The ablation quality of each pulse is very small, less than 10-6 grams, so the total thrust of the thruster is large and the service life is long.

[0037] Example two

[0038] Such as Figure 4 As shown, this embodiment provides an electron beam ablation propulsion method, which includes:

[0039] An electron beam generating device is used to generate an electron beam, and the electron beam is directed toward the target through the exit of the electron beam generating device S401;

[0040] The electron beam ablates the target material to generate a recoil thrust to push the target material, that is, the electron beam ablates the target material, so that the target material ejects gas or fine particles outward, and at the same time generates a reaction Impulse thrust; the recoil thrust pushes the target S402.

[0041] The electron beam generator 101 can be a short pulse high current electron beam generator, including: Marx generator-pulse forming line-multi-stage discharge chamber, trigger-single-stage discharge chamber, pseudo-spark discharge device, etc. The present invention only uses pseudo-spark The spark discharge device is taken as an example to illustrate the electron beam ablation propulsion method in detail.

[0042] Such as figure 2 As shown, the pseudo-spark discharge device includes: high-voltage power supply (including: voltage regulator 201, step-up transformer 202, and voltage doubler circuit 203), discharge capacitor 204 and pseudo-spark discharge chamber 205, high-voltage power supply, discharge capacitor 204 and pseudo-spark discharge The chambers 205 are electrically connected in sequence, and the discharge capacitor 204 is connected in parallel with the pseudo-spark discharge chamber 205.

[0043] The pseudo-spark discharge device also includes: a charging resistor R, an intake valve 206, a vacuum pump connection port 207, a target 208, and a vacuum chamber 209. The charging resistor R is connected between the discharge point capacitor 204 and the voltage doubler circuit 203. The vacuum pump connection port 207 is connected to the vacuum pump and is used to vacuum the vacuum chamber 209.

[0044] The pseudo-spark discharge chamber 205 is used to generate pulsed electron beams, such as image 3 As shown, the pseudo-spark discharge chamber 205 includes a metal electrode ring 301 and an insulating sheet ring 302. A plurality of metal electrode rings 301 and the insulating sheet ring 302 are bonded alternately at intervals. A central through hole 303 is formed in the middle of the pseudo-spark discharge chamber 205 as a transmission channel for the pulsed electron beam. The discharge cell maintains a high degree of axial symmetry and airtightness in order to generate a collimated electron beam and ensure a low pressure in the discharge cell.

[0045] Preferably, the numbers of the metal electrode ring 301 and the insulating sheet ring 302 in this embodiment can be 10 and 11, respectively, and the present invention is not limited thereto.

[0046] Preferably, the metal electrode ring 301 can be made of No. 45 carbon steel, and the insulating sheet ring 302 can be made of organic glass or ceramic. The geometric dimensions of the metal electrode ring 301 are: the outer diameter of the metal electrode ring is 22mm, the inner diameter is 1mm, and the thickness is 1mm; the geometric dimensions of the insulating sheet ring 302 are: the outer diameter of the insulating sheet ring is 37mm, and the inner diameter It is 11mm and the thickness is 2mm, and the present invention is not limited to this.

[0047] in figure 2 In the pseudo-spark discharge device shown, the size of the discharge capacitor 204 determines the size of the discharge frequency, and the discharge capacitor 204 can be 2245pF. At this time, the discharge frequency is about 1 Hz, and the present invention is not limited to this.

[0048] The electron beam ablation advancement method of this embodiment is described in detail below:

[0049] First, a mechanical pump is used to evacuate the pseudo-spark discharge chamber 205 to a vacuum degree of 2 to 3 Pa. Then, the mains power is added to the voltage regulator 201, and the knob of the voltage regulator 201 is adjusted to adjust the size of the initial input voltage, thereby changing the output voltage applied to the pseudo spark discharge chamber 205. Through the step-up transformer 202, the mains voltage is raised to several tens of kilovolts. At this time, the output AC high voltage is adjusted to DC high voltage by the voltage doubler circuit 203, and the DC negative high voltage is added to the upper end of the pseudo-spark discharge chamber 205 through the charging resistor R. .

[0050] Then, air is taken in through the intake valve 206, and the air pressure of the pseudo spark discharge chamber 205 is slowly increased. When the air pressure reaches 7-10 Pa, the pseudo spark discharge chamber 205 starts to discharge stably. The generated intense pulsed electron beam interacts with the target 208, causing the surface material of the target 208 to be ejected outward, thereby generating a recoil thrust, pushing the target 208 forward to achieve the purpose of advancement. The magnitude of the recoil thrust is adjusted by adjusting the vacuum degree of the voltage regulator 201 and the pseudo-spark discharge chamber 205.

[0051] In this embodiment, the beam exit of the pseudo-spark discharge chamber 205 faces the target 102, and the target can be hung in the vacuum chamber 105 by filaments. Under the action of the recoil thrust generated by the electron beam ablation of the target 102 , The target 102 will be pushed to make a pendulum movement.

[0052] Preferably, in order to better verify that the target material moves under the action of the recoil thrust generated by the electron beam ablation, the target material can be designed as Figure 5 Placement method. Such as Figure 5 As shown, the vertical suspension wire 501 is fixed on both ends of the rigid beam 502, one end of the beam is pasted with ablation target, and the other end is pasted with a mirror 503, and the quality of the two is guaranteed to be equal. The detection laser beam irradiates the mirror 503, and the light is reflected on the scale 504. When the electron beam is perpendicularly incident and interacts with the target, the material at the incident point of the target pasted on the beam is ablated. The ablation is sprayed back, generating impulse to act on the beam, causing the beam to rotate. Then the beam undergoes damped torsional vibration until it stops. When the beam rotates slightly, the outgoing light incident on the reflector 503 undergoes angular deflection, and the light spot hitting the scale 504 periodically swings from side to side. The maximum rotation angle θmax can be calculated from the movement and displacement of the light spot, and then the θmax can be used to calculate the impulse generated by the pulse electron beam ablation recoil.

[0053] Compared with the prior art, the beneficial technical effects of the present invention are:

[0054] 1. The energy conversion efficiency is very high (80% to 90%). Under the same conditions, the impulse coupling coefficient of the interaction between the target and the short pulse high current electron beam is higher, so single element metals with high specific impulse performance can be used as The target material solves the problem that single element metals with high specific impulse performance cannot be used due to the low impulse coupling coefficient in laser ablation propulsion technology; 2. The pulse width is tens of nanoseconds, and the action time is extremely short, which can realize the single element of small impulse. 3, the response time of the interaction with the target material is fast; 4, the ablation beam spot is small, the action area is accurate, and the precise positioning is convenient for the advancement; 5, the controllable performance is good, by adjusting the pulse width, frequency, and frequency of the beam source Peak power density, etc., can complete the control of the propulsion performance; 6. It is not affected by the reflection performance of the target material, and can be used to ablate materials such as gold, silver, copper, aluminum and other difficult to ablate by laser; 7. The ablation quality of each pulse is very small, less than 10-6 grams, so the total thrust of the thruster is large and the service life is long.

[0055] The electron beam ablation propulsion system of the present invention has the advantages of small size, convenient adjustment of recoil thrust, high impulse coupling coefficient of the interaction between the target material and the short pulse high current electron beam, and is not affected by the reflection performance of the target material. Replace traditional satellite thrusters.