elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Experimental Verification of Pulsed Electrostatic Manipulation for Reentry Blackout Alleviation

Steffens, Lars and Krishnamoorthy, Siddharth and Gülhan, Ali and Close, Sigrid (2017) Experimental Verification of Pulsed Electrostatic Manipulation for Reentry Blackout Alleviation. IEEE Aerospace Conference, 4.-11. März 2017, Yellowstone Conference Center, Big Sky, Montana.

[img] PDF - Registered users only
5MB

Abstract

Spacecraft entering the Earth’s atmosphere from space are enveloped by a plasma layer containing highly mobile electrons that cause attenuation of electromagnetic waves, often leading to a loss of command, communication and telemetry signals, which is commonly referred to as the “blackout period”. The blackout period may last up to several minutes, and is a major contributor to the landing error ellipse. In the context of human spaceflight, this may also present a significant safety hazard. A new method called Pulsed Electrostatic Manipulation (PEM) was recently proposed to circumvent the communications blackout by applying strong electronegative voltage pulses from electrodes placed on the reentering spacecraft. Through two dimensional Particle-In-Cell (PIC) simulations, a reduction in electron density of up to three orders of magnitude in the vicinity of the electrode was demonstrated. These simulations were performed on the electron time scale ( nanoseconds), with emphasis on the interactions of the plasma with the insulation surrounding the electrode. In January 2016, a preliminary experimental campaign was conducted at the DLR L2K archeated facility in Cologne, Germany to verify the efficacy of PEM in reducing the electron density in a hypersonic plasma, in order to allow for the transmission of electromagnetic waves, thereby restoring communications during the blackout. We discuss the experimental setup for these tests - ranging from the design of the model, including the communication system, to the implementation of experimental protocols. Further, we share data for the attenuation caused by the presence of plasma between the receiving and transmitting antenna, and the effect of the applied high voltage pulses (up to 2.5kV) over short periods of time ( 10 microseconds) on the attenuation. Several unexpected effects have been observed in the voltage response of the electrode, including inductive spikes, stray capacitive effects, and Paschen breakdown of the gas inside the test stand. No measurable change in the attenuation profile was observed for pulses with voltage up to 2.5kV. This is consistent with the results obtained from a Hybrid-PIC Boltzmann Electron (HPBE) simulation of the experimental setup, which are presented in this work. These simulations also show an increase in window duration with the use of surface treatments that minimize the absorption of charge on the electrode insulation. We finally present design changes planned for future tests with higher voltage pulses based on the data obtained from simulation results and from the preliminary tests.

Item URL in elib:https://elib.dlr.de/111512/
Document Type:Conference or Workshop Item (Speech)
Title:Experimental Verification of Pulsed Electrostatic Manipulation for Reentry Blackout Alleviation
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Steffens, LarsLars.Steffens (at) dlr.dehttps://orcid.org/0000-0002-2561-0687
Krishnamoorthy, Siddharthskrishnamoorthy (at) stanford.eduUNSPECIFIED
Gülhan, Aliali.guelhan (at) dlr.deUNSPECIFIED
Close, Sigridsigridc (at) stanford.eduUNSPECIFIED
Date:March 2017
Refereed publication:No
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:Radio Communication Blackout, Blackout Mitigation, High Enthalpy Facility, Pulsed Electrostatic Manipulation
Event Title:IEEE Aerospace Conference
Event Location:Yellowstone Conference Center, Big Sky, Montana
Event Type:international Conference
Event Dates:4.-11. März 2017
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:other
DLR - Research area:Raumfahrt
DLR - Program:R - no assignment
DLR - Research theme (Project):R - no assignment
Location: Köln-Porz
Institutes and Institutions:Institute of Aerodynamics and Flow Technology > Über- und Hyperschalltechnologien
Deposited By: Steffens, Lars
Deposited On:29 Mar 2017 11:20
Last Modified:29 Mar 2017 11:20

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.