Electric solar wind sail mass budget model

P Janhunen,G Mengali,A A Quarta

doi:10.5194/gi-2-85-2013

Abstract

Abstract. The electric solar wind sail (E-sail) is a new type of propellantless propulsion system for Solar System transportation, which uses the natural solar wind to produce spacecraft propulsion. The E-sail consists of thin centrifugally stretched tethers that are kept charged by an onboard electron gun and, as such, experience Coulomb drag through the high-speed solar wind plasma stream. This paper discusses a mass breakdown and a performance model for an E-sail spacecraft that hosts a mission-specific payload of prescribed mass. In particular, the model is able to estimate the total spacecraft mass and its propulsive acceleration as a function of various design parameters such as the number of tethers and their length. A number of subsystem masses are calculated assuming existing or near-term E-sail technology. In light of the obtained performance estimates, an E-sail represents a promising propulsion system for a variety of transportation needs in the Solar System.

Highlights

The electric solar wind sail (E-sail) is an innovative deep space propulsion concept that uses the solar wind dynamic pressure for generating thrust without the need of reaction mass (Janhunen, 2006, 2009; Janhunen et al, 2010)
The Esail spacecraft is spun around its symmetry axis and uses the centrifugal force to deploy and stretch out a number of thin, long and conducting tethers, which are kept in a high positive potential by an onboard electron gun pumping out the negative charge from the system (Janhunen et al, 2010)
The charged tethers experience Coulomb drag with the highspeed solar wind plasma stream and, generate a propulsive thrust that is mechanically transmitted to the spacecraft by a slight bending of the tethers perpendicular to their spin plane (Fig. 1)

Summary

Introduction

The electric solar wind sail (E-sail) is an innovative deep space propulsion concept that uses the solar wind dynamic pressure for generating thrust without the need of reaction mass (Janhunen, 2006, 2009; Janhunen et al, 2010). The Esail spacecraft is spun around its symmetry axis and uses the centrifugal force to deploy and stretch out a number of thin, long and conducting tethers, which are kept in a high positive potential by an onboard electron gun pumping out the negative charge from the system (Janhunen et al, 2010). The latter compensates the electron current gathered by the conducting tethers from the surrounding solar wind plasma. 2r0e0fe0rkemnceofftuoltla-slcmalaeinSEt-oestahliieldrplreEonpgauthlrsti(hofonr system comexample 100 tethers, each one being 20 km long), with 25 kV tether voltage, 960 W electron gun power consumption and 1.16 N nominal thrust at 1 AU from the Sun (Janhunen et al, 2010).

Objectives

Results

Conclusion