scholarly journals Ion Source—Thermal and Thermomechanical Simulation

Aerospace ◽  
2021 ◽  
Vol 8 (7) ◽  
pp. 189
Author(s):  
Victoria V. Svotina ◽  
Andrey I. Mogulkin ◽  
Alexandra Y. Kupreeva
Keyword(s):  
Thermal Loading ◽  
Space Debris ◽  
Outer Space ◽  
Transportation System ◽  
Ion Source ◽  
Extraction System ◽  
Ion Extraction ◽  
Thermomechanical Simulation ◽  
The Stability ◽  
Operating Capability

The main purpose of this work is to conduct ground development testing of the ion source intended for use the space debris contactless transportation system. In order to substantiate the operating capability of the developed ion source, its thermal and thermomechanical simulation was carried out. The ion source thermal model should verify the ion source operating capability under thermal loading conditions, and demonstrate the conditions for ion source interfacing with the systems of the service spacecraft with the ion source installed as a payload. The mechanical and mathematical simulation for deformation of the ion source ion-extraction system profiled electrodes under thermal loading in conjunction with the prediction of the strained state based on the numerical simulation of the ion source ion-extraction system units, making it possible to ensure the stability of the ion source performance. Good agreement between the thermal and thermo-mechanical ion source simulation results and experimental data has been demonstrated. It is shown that the developed ion source will be functional in outer space and can be used as an element of the space debris contactless transportation system into graveyard orbits.

Procedure of Predicting the Lifetime of the Accelerating Electrode of an Ion-Extraction System of a Gas-Discharge Ion Source

2019 ◽  
Vol 13 (6) ◽  
pp. 1217-1224 ◽  
Author(s):  
R. V. Akhmetzhanov ◽  
Ye. V. Vorob’ev ◽  
D. V. Dukhopel’nikov ◽  
S. G. Ivakhnenko ◽  
V. A. Obukhov ◽  
...  
Keyword(s):  
Gas Discharge ◽  
Ion Source ◽  
Extraction System ◽  
Ion Extraction

A New Design and Computer Simulation of a 5-Electrode Ion Extraction/Focusing System

2005 ◽  
Vol 107 ◽  
pp. 21-24 ◽  
Author(s):  
M. Medhisuwakul ◽  
Thiraphat Vilaithong ◽  
Jürgen Engemann
Keyword(s):  
Microwave Plasma ◽  
Ion Beam ◽  
Plasma Source ◽  
Ion Source ◽  
Simulation Software ◽  
Ion Current ◽  
Extraction System ◽  
Beam Shape ◽  
Ion Extraction ◽  
Argon Ion

A 13.56 MHz radio-frequency (rf) driven multicusp ion source has been constructed [1] to produce a high argon ion current density. Milliampere-range argon ion current can be extracted from the source. An in-waveguide microwave plasma source has been utilized as the ion beam neutralizer [2]. The neutralization source was placed 20 cm downstream from the extraction system. With the former extraction system, comprised of extraction electrodes and an Einzel lens, the electrons from the neutralizer were attracted to the high positive potential of the lens. Consequently, the potential of the lens drops and the beam is diverged. To suppress electrons from being accelerated to the Einzel lens a negatively biased electrode was placed before the last electrode, which is grounded, to produce a retarding electric field for electrons. The hole of the electrode was made small to make sure that the potential at the center is negative enough to suppress electrons. All simulations have been performed with the KOBRA3-INP simulation software. The results of the beam shape from the simulation will be presented.

Two-Electrode Ion-Extraction System of a Radio-Frequency Ion Source: Numerical and Experimental Studies of Erosion of the Accelerating Electrode

2019 ◽  
Vol 13 (6) ◽  
pp. 1061-1066 ◽  
Author(s):  
R. V. Akhmetzhanov ◽  
A. V. Bogatyi ◽  
E. V. Vorob’ev ◽  
D. V. Dukhopel’nikov ◽  
D. A. Kashirin ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Experimental Studies ◽  
Ion Source ◽  
Extraction System ◽  
Ion Extraction

Space Debris Mitigation as an International Law Obligation

2015 ◽  
Vol 17 (3) ◽  
pp. 297-335
Author(s):  
Lawrence Li
Keyword(s):  
International Law ◽  
Space Debris ◽  
Outer Space ◽  
Legal Framework ◽  
International Responsibility ◽  
International Liability ◽  
International Instruments ◽  
Space Activities ◽  
Proper Interpretation ◽  
Debris Mitigation

Human space activities have grown rapidly in recent decades, but the international legal framework, comprising of the five space treaties, has largely remained unchanged since the 1980s. One of the consequences is that international responsibility and liability for space debris, which is a major hazard to space activities, have also remained uncertain for years. Nonetheless, States have responded to these problems by implementing national voluntary measures. More importantly, two major non-binding international instruments have been laid down by the Inter-Agency Space Debris Coordination Committee and the United Nations Committee on the Peaceful Uses of Outer Space, respectively. This article argues that, in light of recent States practice established under these international instruments, and a proper interpretation of the space treaties, it has been recognised by the international community that States are obliged to mitigate the generation of space debris, a failure of which will lead to international liability.

Could future COP talks help to de-junk near-earth space?

Soundings ◽  
2021 ◽  
Vol 78 (78) ◽  
pp. 81-85
Author(s):  
Susmita Mohanty
Keyword(s):  
Space Debris ◽  
Outer Space ◽  
Low Earth Orbit ◽  
Observation Data ◽  
Earth Space ◽  
Near Earth Space ◽  
Earth Environment ◽  
Outer Space Treaty ◽  
Earth Observation Data ◽  
Earth’S Climate

Space debris has reached alarming proportions and is growing at a frightening pace, because of the expanding number of satellites circulating in Low Earth Orbit (LEO), designed to increase global Internet coverage and provide earth observation data. LEO satellites are now being launched in mega-constellations, including by Elon Musk's company SpaceX. It is time to completely overhaul the 1967 Outer Space Treaty, which was not designed to deal with current problems. The COP forum should therefore include the near-earth environment within its concept of the earth's climate, enabling the UN to acknowledge, as a collective, the growing menace of human-made debris in near-earth space, and, in partnership with the UN-Outer Space Affairs Office (UN-OOSA), call for a new declaration on LEO.

EU Draft Code of Conduct for Outer Space Activities

2021 ◽  
pp. 153-159
Keyword(s):  
New York ◽  
Space Debris ◽  
Outer Space ◽  
Code Of Conduct ◽  
The European Union ◽  
Draft Code ◽  
The Subject ◽  
Asian Pacific ◽  
Space Activities ◽  
The Eu

This chapter describes the main contents of the European Union (EU) Draft Code of Conduct for Outer Space Activities, Space Debris and Liability Convention. It is necessary and desirable for us to legislate more concretely the abovementioned draft Code of Conduct for Outer Space Activities so as to mitigate or remove space debris. In December 2008, the EU adopted a Draft Code of Conduct (EU Draft CoC) for outer space activities. On September 2010, the EU revised a second draft of the EU Code of Conduct for Outer Space Activities. The draft of the International Code of Conduct (the Code), dated March 31, 2014, was intended to be the subject of negotiations at the United Nations in New York from July 27-31, 2015. The code, a politically and not legally binding document, aims to establish some rules of good conduct for outer space activities. The author proposes the establishment of a new Asian-Pacific International and Environmental Monitoring Organization (tentative title) for prevention and mitigation of space debris.

On the Design of Contact Member Surface Shape of Bolted Joints to Minimize Clamping Load Loss

2018 ◽  
Author(s):  
Linbo Zhu ◽  
Yifei Hou ◽  
Abdel-Hakim Bouzid ◽  
Jun Hong
Keyword(s):  
Contact Surface ◽  
High Performance ◽  
Thermal Loading ◽  
Structural Integrity ◽  
Bolted Joints ◽  
Surface Shape ◽  
Geometrical Shape ◽  
Joint Surfaces ◽  
Joint Contact ◽  
The Stability

Metal to metal contact between joint surfaces is widely used in bolted joints to obtain a rigid and a high performance connection. However, a significant amount of clamping load is lost when the joint is subjected to mechanical and thermal loading including creep and fatigue. In practice, to prevent bolt loosening, additional parts such as spring washers, double nut, spring lock washers, Nyloc nut and so on are used. Those methods are costly and influence the stability of the joint and affect its structural integrity. It is well established that a small compression displacement in clamping parts leads to a big clamping load loss in stiff joints. This paper discusses the relationship between connection stiffness and clamping load and presents a method that improves clamping load retention during operation by a careful design of the member contact surface shape. A single bolted joint with two clamping parts is modeled using finite element method (FEM). A method is proposed to obtain a specific stiffness by an optimized geometrical shape of the joint contact surfaces. The result shows that the contact surface shape based on a gradually varying gap can improve the retention of the initial clamping load. Furthermore, a formula of the connection stiffness based on the curve fitting technique is proposed to predict residual clamping load under different external load and loosening.

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