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Propulsion Performance of Repeated, ...

Smith, Eric Sesto.

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Propulsion Performance of Repeated, Highly Focused Laser Ablation.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Propulsion Performance of Repeated, Highly Focused Laser Ablation./
Author:	Smith, Eric Sesto.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2019,
Description:	293 p.
Notes:	Source: Dissertations Abstracts International, Volume: 81-02, Section: B.
Contained By:	Dissertations Abstracts International81-02B.
Subject:	Aerospace engineering. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=13811139
ISBN:	9781085596091

Propulsion Performance of Repeated, Highly Focused Laser Ablation.
Smith, Eric Sesto.

Propulsion Performance of Repeated, Highly Focused Laser Ablation. - Ann Arbor : ProQuest Dissertations & Theses, 2019 - 293 p.

Source: Dissertations Abstracts International, Volume: 81-02, Section: B.

Thesis (Ph.D.)--University of Maryland, College Park, 2019.

This item must not be sold to any third party vendors.

Space debris is a growing concern for satellites. While most of the debris are small, though still extremely dangerous, nearly all of the mass currently on orbit is contained in relatively few large objects, waiting to be released by collisions with both large and small debris. To prevent an exponential growth in the number of debris, a tug spacecraft could be sent to deorbit all of the large objects. Unfortunately, the fuel required for any single tug to deorbit multiple debris grows exponentially with the number of objects deorbited. Laser ablation, which uses a laser to create a jet of high speed plasma from any solid material, provides an elegant solution - the necessary propellant is drawn from the mass of the debris object, rather than carried to it by the tug. To successfully deorbit large debris will require maximizing use of the debris mass. Other laser ablation propulsion schemes can address propellant efficiency issues by selecting both the ablated materials and their configuration, for example a strip of material the exact width of the laser and one laser pulse thick. By moving the ablation target, they are able to avoid questions about how damage done to the surface by one ablation event will affect the next ablation event. A laser ablation tug cannot afford to ablate its targets only once. This work used time-of-flight mass spectrometry to investigate how laser ablation propulsion performance changes with repeated ablation of the same location on an aluminum plate. The variation of performance metrics was considered as a function of the number of laser pulses applied to a given location, whether they were applied with a short or long delay between pulses, and whether the laser was slightly mis-aligned. It was found that, for up to 25 laser pulses, repeated ablation of the same location significantly improves the thrust-to-power ratio but makes only a small improvement to mass efficiency. After 25 pulses, a crater formed by repeated ablation deflects the plume towards the laser. The time delay between pulses and a slight mis-alignment of the laser had no significant effect.

ISBN: 9781085596091Subjects--Topical Terms:

1002622
Aerospace engineering.
Subjects--Index Terms:

Space debris

Propulsion Performance of Repeated, Highly Focused Laser Ablation.
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020 $a 9781085596091
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100 1 $a Smith, Eric Sesto. $3 3549863
245 1 0 $a Propulsion Performance of Repeated, Highly Focused Laser Ablation.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2019
300 $a 293 p.
500 $a Source: Dissertations Abstracts International, Volume: 81-02, Section: B.
500 $a Advisor: Sedwick, Raymond.
502 $a Thesis (Ph.D.)--University of Maryland, College Park, 2019.
506 $a This item must not be sold to any third party vendors.
520 $a Space debris is a growing concern for satellites. While most of the debris are small, though still extremely dangerous, nearly all of the mass currently on orbit is contained in relatively few large objects, waiting to be released by collisions with both large and small debris. To prevent an exponential growth in the number of debris, a tug spacecraft could be sent to deorbit all of the large objects. Unfortunately, the fuel required for any single tug to deorbit multiple debris grows exponentially with the number of objects deorbited. Laser ablation, which uses a laser to create a jet of high speed plasma from any solid material, provides an elegant solution - the necessary propellant is drawn from the mass of the debris object, rather than carried to it by the tug. To successfully deorbit large debris will require maximizing use of the debris mass. Other laser ablation propulsion schemes can address propellant efficiency issues by selecting both the ablated materials and their configuration, for example a strip of material the exact width of the laser and one laser pulse thick. By moving the ablation target, they are able to avoid questions about how damage done to the surface by one ablation event will affect the next ablation event. A laser ablation tug cannot afford to ablate its targets only once. This work used time-of-flight mass spectrometry to investigate how laser ablation propulsion performance changes with repeated ablation of the same location on an aluminum plate. The variation of performance metrics was considered as a function of the number of laser pulses applied to a given location, whether they were applied with a short or long delay between pulses, and whether the laser was slightly mis-aligned. It was found that, for up to 25 laser pulses, repeated ablation of the same location significantly improves the thrust-to-power ratio but makes only a small improvement to mass efficiency. After 25 pulses, a crater formed by repeated ablation deflects the plume towards the laser. The time delay between pulses and a slight mis-alignment of the laser had no significant effect.
590 $a School code: 0117.
650 4 $a Aerospace engineering. $3 1002622
650 4 $a Applied physics. $3 3343996
650 4 $a Nanotechnology. $3 526235
653 $a Space debris
653 $a Tug spacecraft
653 $a Laser ablation
653 $a High speed plasma
653 $a Time-of-flight mass spectrometry
690 $a 0538
690 $a 0652
690 $a 0215
710 2 $a University of Maryland, College Park. $b Aerospace Engineering. $3 1018393
773 0 $t Dissertations Abstracts International $g 81-02B.
790 $a 0117
791 $a Ph.D.
792 $a 2019
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=13811139