- ,

AIAA-91-1996

Preliminary Analysis Of The Electro-Chem ical Hybrid Propulsion

S. An Center for Space Science and Applied Research

d

AlnA/SAE/AS M E/AS E E

AIM-91-1996-CP

PRBAIINBY MALYSIS OF 'RE ELECIROCHMICAL HYBRID PROPULSION

Center for Space Science and Applied Research KADEHIA SItIICA

P. 0. Box 8701, @ei.iins 100080, China

A schew of the electro-chemical hybrid propulsion has beeii described in tlhe art icle. Fiiialls t o improve in the same tiw the dynamic characteristic of a thruster name- l y tlie s m i f i c impulse and the thrust is the rnaili pur- wse. The analysis and comparison of the dynamic conver- sion for the enerz-stwed PI wi l lant have been carried on. To evaluate the effect of e l e t r i c a l ~airameters on thruster rerformance:. to estimate walitatively the pro- pellant and the thruster construction of the hybrid pro- pulsion ai'e ais, iiitrduced.

l i ~ a t ~ d 11, comparison i i t i , the ivei-y typr of tradition- al electric propulsion system. With rem& to unwieldv and iomi,ie;< ;trciictiire as uol! as tlie km;; amount of the energy consumption it. would be hard s w i a l l r for space

appl i i a t i ill!.

Based on tlle real construction of electric propulsion &velo& i n present and according to the special featu- res of each component of the h o l e srstem, we could com- plete some refurmation. 111 such bay the s w i f i c imulse and thrus t could be able to be increasexi nore obviously. Finally the <ivnamic perfurmar,te of such so-ciilled hybrid propulsion thruster w i l l be mre improved than the itidi- v i h a l elwtrit: or ihernical propulsion. 'lierefore, t h i s kind of "hybrid" should satisfy the actual applicatiotis in space. Just oil the thsis of the inwgination soire coli- cept investigation and initial analysis of the electro- clmiical hybr i d c,rwiiIsioi, lmve ken vrew~ted concisely in the pawr.

I t i s wel l known to a l l that the proreellant is workinr. uilly as the iniitiiini t i , trmst:>i werdy from mwr source to a thruster i n the traditional E.P. ssstem. I t is one ot llie I~K~SSI y part "1 iSi* system. I t s rhrsical Jiara- cterist ic and weight a u u n t vi 1 I give obvious infliiei~m

UWIL the &eitcii~l f & ~ i ~ e C I I L.1 . sstkni. stili a s tit.- ra- t i o of thrust to total weisht. the ratio of thrust to wwr irtptit. % k i f ic imstifs:, ttirtist. I:

on. But in order to advance the dynamic characteristics r ,a r i t io i~~c~~ above. it i j 1 i m i t . d by the POW level which will be ProviM i n orbit. Therefore, without increasinr: the thrustei wwer irwui i i l the orliit tlie dynamic wrfo- m c e of the propulsion system can be improved, i t w i l l b very excitilii i i s Supwse we' 1 I find out a kind of the propellant which only spends a l i t t l e amount of erlercy power supply p r w i k L u t it is able t o transfer and convert much energy stored in the rropellant orisi- i f i t 1 1.v. I t JUS( t.h+ oid.staiJii,c. feature of wowllant we wnt to f i n d for improviriR the traditional E.P. system.

I t nteaiis Lliat ti;:; pIu~*.li;li~t is i r i g i of sone substance which has to spend some energy for its norm1 workins in

the E.1'. propulsion system. the prowllant must be gasified d e c o d and ionized. these processe~ have to ex& the eneray. k i t utust be ProviJkj by an indi- v i h l power source of E.P. systen. Ihe most iportant characteristic we i i d is that before i t is on board the propellant has already been charged by interim enera, so we ca l l i t as energy-stord. (in the contrary the pro- pellant d i n the traditional E.P. system spends s o ~ e energy too b u t no arty interior energy has been contained but the propellant for the traditional cheaical propul- sion is purely a carrier ut eneru. I t s amouiit presents the level of total energy of the propulsion system, so the chemical w-opulsion has the enerm-stored Propelhit either. As we m a r e chemical propulsion with the ele- ctt ic pi-wulsiun. i t slmll be found that lor the former the power source is the propellant, but the power source oi electric pivpulsion Ius to be muippd especially and i t s propellant could never provide any e n e m neither. i i i other hand i t still coiisuw some energy a n w . When the enwgy relationship of the propellant in traditional electric propulsiun s y s t i o is i l ~ ~ ~ a j . i t wars that t.he enemstored promllant are used instad of the general eim~rr-cixtsuuhl theit this inew E.1'. systiiu Iwk like to increase its total wwer input. I t w i l l create the necw W Y conditim of i w o v i r i the dynaaii m f o r m c e hut without any increase of original power capacity. I t has

iie links. 'llnis teature ~ o u l d bring winter efficiency than the traditional E.P. equipment. Fig.1 shows the 'U

structure diuwam for e k t r o - d m i c a l hybrid propulsion k i M in the article.

I t is seen from Fig. 1 that by using the enerastored pi~omllarrt except the e n w a irwut from the p r i m y powr source, one can get again an d i t i o n a l input part ut energy E,,., proviJkj by the prowllark itself' b u t in case when a tranditional electric propulsion system was a w l i d this aditional IWL uf Ep- should be mual t o TWO i.e. E,,,,=O. With the eriex&ored propellant the aiwunt ol i r m x y of .:.I, c o n s u d by the propellant whm i t has tu be gasified W and ionized for f u r t h e working. is I- tllaiir L,..." which c a s f'roni promllant. It, m s that LP c. < E,,,. h t is why we call this k i d of E.l'.which uses th* energy-stored propellant as a electro-chemical hybrid propulsion. In this case the in- pu t power irk" thruster ihamber has clianwi from arnount of 11 I rl7 11 &mV into 11 I 11 11 &tn.+ II 3Eppo. 'lie ina.ease uf ~I&....~~ is j u s t the smiul featui-e of

ECHP (electro-chemical hybrid prwulsiord. h u t the de fiilitioit of effiG.ieiicy se~ latei

'rlithout any alteration of thruster structure b u t oinly by the ixiliansr of PI -OWI laitt frou the e t ~ e i w ~ o i i s u d t o the enerastored people vi11 be able to improve obviou- s l y the dyilamiial wfornwnces of the thruster. For the

L

-\J

L

Fig. 1 Configuration of Elwtro-chemical Hybrid lhruster

Ernm : electrical power input i p : consmtion for propellant

reaction E,,, : internal energy of propellant LPD :> AP r( I : efficiency of enerw conversion

of primry pow& w r c e 112 : efficiency of en= conversion

11s : efficiency of thrust chaaber of pow d i t i o n e r

L

to te i r d i i a t d that in this hay the ionversion of the interior energy of propellant into the lpechanical &- uiL enera of thruster is dii.eitlr cowletcxi through the discharge chamber it isn't related to the pow convert-

Propellant has i ts interior energy the propulsion systes 1% no lrmj t~ inirea= the pow i i w t but i t ' s able to

energy of prmliard. an be rel& by SOW m e r . raise the output level of the thruster when the interior L

i

Lbsic Uyrrailii Relatiunship of ECHP Y

. -. In electric m u i s i o n S Y S ~ the r s t principal b- miL process jlio-s that the electriial wwer input has to be converted a t last into lnechaniwl h m i c energy of exhaust stream. I t is very Llear e lec t r iu l power input is ttte min energy source a thruster will have in orbit. 11, ;omparism *it l l tbe iowi,,tional C.1'. system the ECHP presented irg tle article has some differences in the re- lationship of eners)

Tne followirts table Tab. I has pointed a t the discrep- aicy between the tranditional C.1. ard the KIP.

I t will be knowom when the input enereJ EtnD and the eSSlLit>ncy GI ionveision of G Y S ~ N II are identical for

D i fferertce of energy re la t ionship between t i anditioiilal El: 0 EcllP Tab. 1

IianJit iwal !T ECllP

thrse tm tries of piropulsion, ht the efficiency q co- rtsists of several parts. r m l u the priwrv p o w sourm

~ ttrs *onJai..v p o w ioinri-kr and the thrust clwber, every tm of propulsion system has i t s OWTI power output 01' the r e o l t ul' c4uasical Loonversion. 111 adi t ion, each differs from the other. 7he relation between them can he il itten as .iuilo$s:

the ratio E'-*. but should be m a t e r than unit. Tnis v a y clwrly irdiciltas that the electro-cliemical hybrid has its superiority over the tranditional electric pro- wlsion which has been w u i d with the propellant in cosan use. aviously, L L will be proportional ti, !-L Ctutal imss of' propellant for m i s s i d . I t must be I&> 0 and i t ' l l be related directly to the fl ight duration. In k t there must be silnie m u r k of Ib for any mission. If one did not t o uti l lze this potentiality of A L P pro- vi& witl, I& i t m a n s that the charm wi l l be given up

for nothing. In owtsite, the mndition had been created for utiliziiw the wtentiali ty of the aditional energy of A&, provided by Ib, t h the thruster. will be pro- duce hidiet out powei. Gnmquently, the w i f i c iwul- se and the thrust of a thruster both have been increased unhubtedls- .

In shwt, without charsine thnlster structure and the pow input level as wll as k w i w the same efficiewy of system conversion, m e excellent output perforwnces could he reached by the electro-chmical hybrid system.

The exhaust dntmical energy E'- of ECHP is the main Part of the vower output E'*,*. of the hybrid propulsion. We are able to &ce ttte followinss:

P ' ) ~ = l i n v ) ~ 9; E'&" = 14)

dme E',.,,T. is the p o w output of MIP IL i s the pow output of tranditional EP

11 is thi conversiun effiiiencr sf EHP system L L , the additional energy from propellant

01 u t t a iimpI= I-e::omlatiul~ i t will k <ut next:

E',,, E,,"< =I I ii L - E & D . E,,,,+ 2 1

where 11 the system efficiencr of traditional EP horn abnve rt.l:ttions we a-e able ti, eet sloe conclusi-

on remrks. 'Re thrust F', the specific iwulse I'SP and the efficiency of the IiybriJ pro~ulsior~ a l l are concer- ned with the additional energy AiL- which mms from the ener.wsmrei ~ r o w l l a n t YOU have used. %e effici- ency 11 presented above consists of several wrts, i . e.

where 11 t efficiency of p r i m energy source I I Z efSiLieii8.y of wwi' conditioner

rl II conversiorb eff iciencr frm electrical power into thrust thrwgh the thrust charrber

I t has to be indicatd that fw el&,ro-che~ical hybr- id systen i t s system efficiency will be slch higher than the t r a n d i t i o ~ l because the additioml energy from pro- pellant i s directly introdxed into thrust chsiber but not throush any other conversion &stem. Here we have other reason to mve EMP has higher systea efficiency i t searis i t s pow irrput had not t e n enhanced in coma- r i m with the t r a d i t i m l E.P., the additional powr or energy iiwease had been got fully without any expenses.

After t r e a m t of above relations, the cMparison of sme wapetzl-s betwen the elcctro cheuiial hybid SYS-

tea and the traditiavll E.F. can be witten as follows:

Re ratid f a . thi-ust

n e ratio for swcif ic i m l s e

L = F ’ F

I t i s very clear that vhen we use n hybrid propulsion system we cam a l w s Ililve hisher performnce of thruster in - r i m with applyins the thruster of the conven- tional E.P.. b re the -L aid w e the advaitage of ELW. when enew input Etrnp or system efficiency t i and both of them is low the FLIP will k r w e effective.

But one thing should be pointed out when ECHP h a s been in o m t i o n r)iaLtlr i t s imvwsion ef‘fiiiency of energy will be differmt from the conventions1 E.P. as they & not work with the saw energy level. Sup= both system

have the sw original p o w inwt Et, and conversion efficiency of the Mnrer conditioner. I t m s that both system have the sw rl 1 and rli. as Et, identical and we have 11 1 ’ 11 ?=tin but the efficiency uf the thrust cliaraber II I will be different as they hove not t h e sae i.ii imtalice. for the lubrid the tutal energy in thrust

chmhr has been already higher than the traditional. \le can set the fullowir~ relations tor cowariix these

two systps. I t will shirw the benefit brought f m ELW.

W

L

I; = E’”.,. / L,,,* - I.’,*” / Cn”

*ere FH = -E.,. Ern- lhis formula shows the ratio of output for twu syskns

&pen& yn FIL the ratio 01 eileryr ProviW by propel Iat to the energy input from the wwer source.

kxording to the equation (91 we will be able to k-- r i t e the s i i p e r i u r i t y of tlge DXP. Fih. 2 t v Fii. 4 have indicated the tendency of G= f (FH, 11 ’ , II . II 01 vhi le tte

mrawtei’s u l G ait: equal t u difteimt values. Tat.2 shows the numerical exmles of the equation (91

Un the p r u ~ e l laet ‘ L i

L As mentioned above the tradit iord FP systea has used

such mterial as the pi-~wllant which rust spend sme of energy for the normal working. so this i s the substance ionsumiw enei’gr. hen though the selectim of them has diverse possibility, but wherj i t has been used in the EF’ system sow w u n t of eiiergy has t o tr bromht in to the thruster to gasify. derolwse and ionize propellant. X course differerat rwterids ~urwl l a r t t s l have differalt. enera consuwtion. For the electro-chemical hybrid pro- ptilsion srstai iexl kicks saw aemral i-euuireaert t l ~ Ep prwellants have to wet the material has to contain tln iiitwiur HWLY tu i tsel l . I t wails that scm mi l t ,

of e m has to k stored in i t . And under certain c i r - ~watalces this iiiterior energy could tt. released. Such feature will make the product of thrust chamber to briw hi*rlier eneroy than the traditional m-ewgystitred pro- pellant or i t s situation i s quite different frcm that in i w i i use. For e x w l e , w e deco.po;itiorBs hisher a- peratwe and etc. Based on these the pro&& fms h i d -

L

thrust ck&r w i n w i l l te heated, ionized and accele- - rate? with t k eI&rical m w g y once wr2. Fiiully wre effwtive exhaust dynamic st.resn will te given.

It has to emhasize when ye take this hybrid thruster into operation. y3iw problew should Le solved at first.

.-I

Numerical exawles of calculation given by equation (91 for different parameters Tab. 2

0.5 , 1.02 1.04 !i.o6 ;i.oa 11.10 11.12 i 1.14 i1.16 i 1.18 11.20 i . --- -~ 1

0.6 ' 1.0166 1.0333 i 1.05 ' I.=! 1.1 ~ 1.1166 I 1.1333 I 1.15 I 1.1666 I r---, 1 I -- i f

, 0.7 ~ 1.014 I 1.0285 ~ 1.04285 I 1.0571 I 1.0714 j 1.0857 ~ 1.10 I 1.11428! 1.128571 1.1428 I ~ 0.8 1.0125 1.025 j 1.0375 j 1.05 1 1.0625 1 1.075 [ 1.0875 1 1.10 -5~ I 0.5 ! 1.224 : 1.248 11.272 ~ 1.296 ~ 1.320 ' 1.344 11.368 ! 1.392 ~ 1.416 j 1.44 I

1.24 ~ 1.2G ' 1.28 , 1.30 I 1.32 I 1.34 11.36 , 1.38 , 1.40 I ..... I~ ..: _.__ & I 0.6 ~ 1.22 1.2 ,~~~ ..:

0.7 ': 1.2171 i 1.2342 ' 1.2514 1.2685 ~ 1.2857 I 1.302 I 1.320 I 1.331 i 1.3S42i 1.3714 I . . . . . . , ......... . . . . . +---' ,--!-+ 1

0.8 ' 1.215 , 1.23 1.245 1.260 ' 1.275 I 1.290 j 1.305 I 1.320 11.335 I 1.350 I

_---.-

....

.......... r

I

-,-; I!f---- I - ~ - _ _ _ ~ I

-

'he prupellmt mat,erial khich is able to meet the re- qnireioliit io an el~trochemical hybrid propulsion system my te telon~ to the followings:

I, &lid PI-owllaiit i u d for chemical propulsion; 2. Material having ability of exothermicity; 3. Oxyeemtit arid fuel bipi-wellant; 4. other substance releasirs rnerg~ durins readion

Irith tile kind of energy stord inaterial instead of the in a w n used propellant for general E.P. S Y S ~ which has w any interior energy . at lmst one can replenish quite cuKmt of energy on board. For exaple that's w- sible sme chwlcal reaction substances can probce sev- ~- eral 10' even a r e Joules pep each m wight. &re- fore it should be very attractive to apply this kind of mterials for space flight of lona hation.

./

Such as: 1. Controlled reaction of materials (propellanti; 2. Configuration of propellant feed system; 3. Duration storage and safeguard: 4. Pollution

h n g these the controlled reaction will be the kernel topic for electro-chemical hybrid propulsion. Sowthing like in Pi" (pulsed) or WD (qwisteaQ) de, How can be realized a reaction of enerw-stwed wopellant in so short &ration of several n i m or aillisem~k ? It has to do m e research on the reaction winciple, characte- ristics of reaction .aterial, control .annet-. work situ- ation and so on.

How the &ion muid be under mntrol and there are IIU I>& of the cwlicated structure for the wowllant

5

L .* L

.OI .oz .03 .04 .05 . 00 .07 .08 .09 7. 0 wt

a

*1.4

1.3

1.2

1.'

l . C

0.9

ti.8

ld.T /

I L T .I .a .9 1.0 1.1 1.2 - 2

Fia. 2 Effect of k of Emrmr-stored ProPrllaot. On tk lkilefit of EIIP

fw I1 ; 11.1.2 - for f l ' / l l= l .o

~ tor 11'/s-0.8

G=f(FM) , tl"=O.s, _ _

Fia.3 Effect of 11n,o0 G , G=f( 110) /i ' _ i /I :1.u

for FFI = u.1 - form = 0.05 for FM = 0.01

- . - . .. . . . ..

c

fed subsyst,m. Hasla SiJiw k i i o i l d ~ e abut solid propel- lant, owgenant and fuel of the chemical propulsion vil l be helpful and to ietrduce ce-tain reference. According to the usage of tetrafluorcettwlene for PIT and W D a t pfese-it: it has sone advantigs over others such as sim- ple feed confiwation. convenient storaze, safety. re- l i- , . & I i t u . huppxe sow iumbirstitle and iornbustion--sup- portinp eleiwnts could be mixed into with IFE under spe-

cially k i a i i a t e i t~.ircur&mce a hish sped chemical re- action could be formed, then a large m u r k of energy i s able to be PI <c%JL~. I1 would k the ms t convenient.

'4 -

ktimtiot i of electrical paranetem

'bile the elwtru ihemial hrh-id propulsion &scribed in the article has been accepted only one coownent of tiuuster has t o be chalwd. I t should be the Propellant. ( include i t s f e d subsystem and control as well as sto- r%e I . U l i t the elmtr ical wwer cordit.iiners wttiih must be relatively convenient for pr&irg charged Particles OT plasm and acceleratilja them to required velocity are s t i l l the win cownents which should not be of absence anyway. llere I'IY (oi. M'U) 01 elwtrommetic system has been taken as an exaxple. Regardless of solid or gaseous pruwllant 1 1 4 i x the thruster the discharge wwesses u s u a ~ ~ y may be pulsed or quasistealor mode. In mor IPD the production of plastin w d i t s acceleration t h e s e two processff are cornbind together. i t hard to divide each other. From the wiills of vier of the power source t h e two phvsical phenowna are wkins: with sxe pow set.

In fact i t can be considered as accelelratinp plasm while i t s p r r h i n g . I t means that both phenolpena have aweired aiwltanevuslr in dizharge rMion. nmt's very

different from the electrostatic Propulsion which every Process i s strictly Xpai~aW. I t is not reasonable that two different physical p r c c e s a ( t o vrcduce plasma and to acieleiak i t 1 have bee11 f i n i s l d Nitl, a comn ne- ctwnical ctructure and a cOwan power conditioner. It. is ewal to YY there is no diffei-ence aamn the different phvsical mxeszxs. Obvicuslr. i t is not possible to de- velop the wtiual pert'ormiie tor each process. As electro-chemical hybrid pmpulsion has to apply the

e n e r w ~ s t v r d prupellant ilriih will be the reaction oa- terial under certain conditions, so it is not reamable tu use the elmtr i ia l structure of the traditional elec- trolpawetic w w l s i o n for =tins the resuirements of the hyhrid thruster. Ve twve b l i rd a new structure of pow conversion to leet the different r e q u i m n t f m d i f f e r a t pllvsiLal phei-menon in ordeI to fully develop

k~ *

'-'

--,

.J

the advantaw of the IXIII'. into two section

each will be a:onuatibla f'\n i t s special physical process and in the saue tine a cwresponding power converter has been prepand for each mxhanical part, tlneii the EolP is an ideal system which will be dust reflecting the nrigi-- nal thinkiiis. it wens each par t will be related to pro- duce plasm and i ts electromgneiii 3Pceleration res=- tivelu. !&be such mthd is mre suitable ta awly ECHP in Practice. So there should be two converters of energy exchanse. nie reason as f u l h s , a t fiist PI-owllant ill hybrid operation will be required to relwse i t s inter- nal enera for getting the equivalent additional input p o w so the dischawe process of ionization period has tu neet the rewireoent of propellant reaction. %e ele- ctrical parmters should be determined by the characte- r is t ics in this duration. 'he discharat. WJZ of th i s pe- riod should be mt requirement of enera t r a m i s i o n fron e l & - k i t r to the propellant. I t wns betwen the discharge PTOCLSS and pl-opellant reactioli there must be a cowati t i l i ts of tire duration. A ielation of time can be written approximtely:

If we can divide the hybrid thruster

where tl.dl.: disclrge duration in thrust chiuober L: reaction tiw uf prohlllant 7 : tilleconstant of discharge circuit

Lastly the pwducts from discharge has tx be accelera- ted with electroeametic oanner. therefore the pow set for accelerating plassa should be Painly beneficial to this working situation. of cwrse the discharge duration of this w i d t . d t a sl~ould ke useful tu accelerate the mt particles from the thrust chaPber or plasaa M c -

tion wtioin. :e could M u w a relation foi i t :

& . d C - G' t<.d<a

'he t i = wuem Of ta.d!. should be a l i t t l e lattel-

Hybrid structure project has i t s om sPecific features not only in the meclwniwl comments but also in elec- tr ical W s t m . Haybe i t lcdts like there's some cmp-

lication but there is dlso the wwtunity with w e and w e options to realize the optiaization for a m*pleted propulsion system.

than t?.d,-.

7

Structure consider-ation of ECHF

Fig.5 presents the structure draft project for a elec- tu-cliemical labrid propulsion system. k we want to u s e e n w w s t o r d and reactive materials the ECHP system has a complicated prupellaiit feed system i n cowariwn witli the simple electric propulsion t l iuster. because the m- terial lms the feature of e m - u stu(.Rj ability aid it is needed to release its internal e m , but from other sick there is diversity of exothermic: ireaction of diffe- rent .aterials and their ckveloping process. So i t wuld provide much opportuiiitr to select. a moiie suitable subs- tance.

the suitable wwer structure t o release internal energy, as the currefit lias wre 1OnR duration ahid there is much t i w for energy exchange wi th the propellant. With this means the iiter ior energy a n be libel atni easy. For the electrommetic acceleration the power conditioner mytr completed by a slowly &nwJ. s l i g h t l y protiastrd si i iu-

soid4 oscillations or a series of pulses. In a word hi;en ihe elatro-cllemical hybrid Propulsion

has h selected, the &sign of wwer conditioner could be able t o Ix Finished accordiiib to the 1,wuireants o f releasing internal energy and acceleratiiig plasm resce- ct iveh. ;iierefi,ire it . ha5 nux reasonatleriess and f l e x i - bi1it.y to &cei-mine the power conditioner of ECIW.

(in tle h i s of i&a a i l i i a d ib., t k paper the 'mha iiccll structure of CCllP should have a separclte component

L,

L

I, I power I -

r\ io) d i t imer 1 I

I I for accl. I I I ?---_-__J

- 1 I i

I power I-+ I source I I - 1

I

r n l

I

I

I . I

IproPellaot-section- TL~GZT . r i-1

L I subsystem I ==== I for Producing I ==== I acceleratina I I

I for ElP I -- I plasma I -* I piasma ' I - L__J

. i I 1 wwr I .~

&&l for I-- 7 pi.&. plasm -- -- route for supply of prowliaot - roiite of power

/ ! Fis.5 Structure schematic of electro-chemical hybrid propulsion

I

ils gasification of propellant or release of its inte- rior energy lias different physical feature in cornparism

with the process for accelerating of awus Propellxlt which has already been i i i tha state of plasm, so every process has its ow respective wwer conditioner k i m - SI by its chwacteristiw. i h i i t it SUM diswssion has been described in the forller uarawapt. For example the tiio wwer converters should ke compatible i d enuudi i n t ioe sequence each other and we should understand as the fuiition of each part is different therefore their work- ing pode a l so sholild be different. Only i n such way each part could be &awed m e . llie discharge of a b i n 8

characteristic or witli a square waveform nark is one of

construction. I t iwar,., the !,ti it$:twe ot I eleasing enerc:y w i l l be an individual section which should not effect o~i the successive acceleratii,e ~rcc+ss. I t wst tz aLle to provide a larse nunter of charge particle i n high enough energy level and t.o iaisa nnre wurk tani i i .at i i re in dis- charge chanter. The structure of plasm acceleration has to be able to met die I-muirewnt of plasm jynnmics.

A5 the consideratim p r e s e n t d above has Lee11 rr:atrd tcl every pruiej5 of ilmlc plrupdsiola systkin, the ,char;(,.- terist ic of vi11 be inprcwd as expected. %e siic- L

LC;_S wchwtilitj . i l l be l c i~ l ,~~

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a

u References h i liusior~

u 1. W d Igenbergs: " Or, the Simultaneous &ration of A Coobination of Chemical and Electrical Rocket Ensines "

Jownal Of the British Interplanetary Society VOI. 29, pp 195-211 1976.

I t i s clear from the initial armlvsis and discussion dacribed iro former paragraphs that hu iisins elzctrcche- mica1 hybrid Propulsion the EP performnce is able to be advancmj i l l comvariwn with the some present traditional d,ile it i s lio need tu increase the r u m input and also IK) reed ti, t;harlee arrailr the mhani ia l structure. Only suitable propellant material has to be choiced.

by difleren:. w m h r u conditioner for different sub-

system and usirs different a ~ d ~ a n i c a l structures to each parts tor releasing i n t e r i m ener6y of mtwia l s a d ac- oderating the plasm. the m i b i l i t u of iwrovins t h - ruster perlornurice kow5 nu~i-e real izd. At the saw ti= the idea of t h i s kind of hyirtrid Propulsion presen- ted in the paper Iws sow rwileii~eew-tt such as to further

trill i t s riractiml t o build reawnable power conditioner AIM 87-.1092. 1Sth IEPC May 11-13 1987. for p r o ~ l l a n t miversion and for acceleration of plasm to f i rd e f f d i v e m)ran i in l :,ti uLture of different pur

poses and SO on. III addition a iwsonable owration loode ot sucl~ a thrustci is sti I I an quite imwtmt subjmt. But the final conclusion renurks should be verified only tlii ough e n o u d exim ieiks. As the brief sumry SOW tentative opinions have k n

j ducd in the fvlluiviiia.

2. F.R.Chang-Diaz et al: " A Tandem Mirror kfbrid Plasm Propulsion Facility

IEPC 88-l2G, 20th IEFC Proceedings W;LR k r i c h t 88-02

3. Qian. X.S.( Tsien. 1i.S.l : Introdutory,on Astronautics "(book in Chinese)

4. Gary R. garf : " Ihe Plasm Drive from Costa Rim "

5. An, S.N. & b, 1. J.: " Review of Chinese Electric

Sciences , k i i i n p , 1962.

Space World, .iune 1986

Propulsion Developments AIM 87-1101, 19th AIAA/W;LR/JSPSS IW:

to investigate suit proprllant. to know con. G. An, S.H. : " A Reasonable Structurt: for D i d m e Type Plasm Source

Colorado Springs, Colorado U.S.A.

'-

1. Eclip has a relative simple structure: 2. UY sa l a t ion iof suitable enerw-stored propellant

and usins w a r a t d indivicAmlly rwchaniml stru cture for r e l a s i e p energy ot prowllant and acce- leratini: plasm as well as with separated power iwdiLioner foi diffei~eut y w ' m , it i s -ible t o form the ECHP. the thruster wrfonwnce will be iwrovd. I t neans htlz of tlvust and s m i f i c im-- pu lse will be iicreased simultarwusly:

:. 'he I i w I efii<.ieii,~y of WJwer a:ondiLioner rust excharm the h ide r action of ECHP;

4. Urdw I v u ; ~ ~ iiiput w<ei Einp the ECIII' system w i l l give mre benefits;

5. 'he results of ECHP is prowrtional to the amunt of mw-ey the piropel lmt. ,:ont.aii,s

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