-9! 96 - / $& ( $ %+(,+ % & '$( %* $ / 6/ / - - * ( 6 C > DEF 6 k?@ < g s < 6/ > :-; < - 9 P - 9 C L M N O;L J :-; < H IJ G H : U - - G S - TF - 6Q F - : Z [ - DZ Y TJ - < H6Q?M < X: V W: / S - I?P < Z H \V - < M < 6 \] X: ] :-; a@/ ;U _ %/ : ^M Z U - S / - Z [ b^ < 6Q G F T^?:< < O;L Z H C > DEF cm :-; :: + Numrical Phnomnology of Plasma Flow Nar h Elcrods of a Magnoplasmadynamic Thrusr M hangar rospac Enginring, Shahid hshi Univrsiy, Thran, Iran bsrac To simula h plasma flow in a magnoplasmadynamic hrusr, wih mass flow ra of g/s and oal charg currn of 6 k, h magnohydrodynamic quaions accompanid by an anod shah modl hav bn solvd In his modl, h flow hrough anod shah rgion has bn considrd as a collisionlss and unmagnizd plasma Undr his circumsanc, by drmining h dnsiis of lcrons and ions, and by crizing h Poisson s quaion, ponial drops along h anod surfac hav bn obaind Th numrical simulaion has proprly rvald h phnomna such as dns inrnal flow, hr js and ho spo nar h cahod lso, h acclraion mchanism of xhaus plum has bn jusifid basd on h concp of virual nozzl and cahod j phnomnon Th valus of maximum mpraur and hrus hav bn prdicd in good agrmn wih h ohr numrical and xprimnal daa, wih h rrors lss han % Morovr, lcrical characrisics of plasma in viciniy of anod such as h invrs dpndnc of anod fall wih currn dnsiy hav bn modld in good accordanc wih h masurd daa Kywords: Quasi-nural plasma, Magnohydrodynamic (MHD quaions, Virual nozzl, nod shah, Cahod j Do C P Dm - / _ F:< g g < ( pm < S HJ ^P C - g :-; P Z < ] g - ] < S C P 6 qu M MPD 6/?:U - j D : r ]? DZ - :-; >] qp - I Ns g ] < : > ]? - ^- DZ Ig I O;M V (E Q @s J ap :-; < ]? O;L vu :v-; v< cmv 6Q O;M I ( J Z < u ( n n v i O;L TJ? v- M U - I ; - C :-; 6/ _ / X: f \Z < M I g < - N ( MPD ' : - 6/ 6/ N J N - / g Z F^ [] V > ( S?J c > I 6/ H:U 6/ T9VP / b] ( - ] U / < G O;M J J I/ cm :-; < - cm j c?@ : k n S Dm F 6Q - cm - 9 Shah Quasi-nuraliy Magno-Plasma-Dynamic * m_ahangar@sbuacir : 9//9 :! 9// :' (!
F>? V H > \ 6- - DEF IJ MHD DEF ]: F- MHD '$(?E >E : - < - -P ] > - 9 P C > 6/ DEF IJ > jj >] b^ s < - < ( U _k - < -P j6 TF- J ] : D] IJ 9 < j6?g DF^ < F- HLLE- T ' >V k S : S F j6 < ƒ O;M IJ g T _] X: - V- H j/ MUSCL ' 9 - U O; ^M >-; MUSCL ' S Z U [ @: Z 9 : Q F L _ H Ig :-] H - H ] ']C H D z?j U j6 S s Fg J TF [] x< X: sj _k - V- HLLE- T - ~P V ' -P ] H U IJ D]< s _k - F^ Ig M x< : G S ( -P O;L H > - / H D]< - _ J g g - Dm ( TJ / Z _k D6 Q D? o Q MPD 6/ J w S ] O;L J G S [] x< ^: [] O;L D? 6/ O;L G S \? / D6 P /?@ < ( z \ G (D6 /-/ ;U < C {? 6 ( G % J - n S % J P O;L J S? D J Do - ] % J D6 6/ : J :-; < a@/ U _k } /k [] x< -? V Do DEF U:Z J D z - - ~P w < Do Z DF^ X: - DZ \ :-; < < / / 6/ < M < w ^- < [6] 6 [] Q [] - Z Y J :-; < w / \] D]< - / - I?P U Da ] \ DZ :-; < U - 6 %+( + FG H - O;L J @s - J [] Z DF^ - T?o '] - 9 M E :-; NF N - [ 6] _: 6 C :-; 6/ H- IoJ -P H?- C S U 6 - - - T ( λ mfp λmfp λsh O( Q J ( λ sh J Dm M < ( - :-; N O;L J < ( TJ - < o s Schm Collisionlss Plasma Larmor adius Z L ;U T [] ( mk T Z L λ O sh ( j ([] (? >? '- $( % MPD ( - < a@/ - sj _k O - Z :-; < > C > 9 MPD C > 6/ > DEF IJ F -P G T-P 9 ;U - V- (MHD Magno-Hydro-Dynamic Equaions
6 m d dx ( u dϕ dx j ϕ ( x u( x u, + mu, 6v-v TvF v O;L u U n, r n( x + ϕ ( x mu r (, ( T^ 6 6 ( Tv^v (v6v< v v jm ( r n u r n u,, o S X: r r + x - o UF - x P ( π ( π j r n u r (9 M Vo P < 6Q F V- ( Do F 6Q j r n ( x u ( x r [] M F -X g V- Π ff j T xp kt 6 m K ^- Π Π ff x / z x E π Π Π ff T j ( ( ^ X: - -X s 6 - - T^ V- ^- ( ^ \ - S Hc - [] G S TF V- X: mu ( ϕ ϕ U k T E ( IoJ ( T^ ( u U - u ( U + ϕ ϕ m ( T^ (6< - I G ( M Do Dm 6Q ( TF ( j m ( ( r n (6 x ϕ ϕ x U + r ( - TF (6 (9 (6 (6< ζ xp( ( φ ϑ νφ + + ςφ ζ + J + ( φ φ U ζ U IoJ F TF ζ ( D z P [9 ] - C L 9 o - IS C Dm F 6Q O;M O;L J - >: C ( - 6Q - - g E n i n n ( _ IoJ F 6Q Iv F Vv- - n - ( F v I - TF ( TF ( E ϕ ϕ n i n n \]? ( I T-P 9J; 6- \ DEF C L M :-; < n n i ( ^: S F S F 9 jj \ DEF P V- ( n M u u p + n E i i i i i ( n m u u p n E [] Do J - U - Q z u \ TF [ ] ( v, i kth M Do - - TF - :- Dm F 6Q dni dϕ kth ni dx dx ^- :U O;L u U - x x ( ( J U - @ P - ( P - V :-; P ^S - F ( ^- b^ ( O;L P T- PS F Da@ <j ( z P ( r UF - ( < x P - TF 6 6 HJ jm - ϕ ϕ ( x ni ( x ni, xp (6 kth -H x O;L J 9J; ] U - - U - u [ ] ] ( v k T m J - Do x, - \ TF - ichardson s Law Effciv Work Funcion 6 Schoky Unmagnizd Plasma Thrmionic Emission Maxwll olzmann Disribuion
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- PFS 6/ F- -P / / Y TJ - : ˆ DZ T -?M < ( F L _ H 6/ < M - < M- H6Q - Z- DF^ IoJ Z D/ / 6 Z H \V F - I?P MPD 6/ < M :-; < V - ap :-; < - < 6/ < M U - TJ C H Do H I b^ J - { ˆ Z :-; < z? / U - H J G D C / U - - : T T I :- T G U S ^M M M S X: - % cj Z S < 6Q G F T^ F- _ Z b^ _ / / U S 6/ O;M %/ : S S ( m ( T C ( Vm ( N / ( k I?@ < ( m < 6Q - - / ( JK ] z : ]< > Dm F 6Q -9 /6 - (9/9 ( C J kg \ < ( g s 6/ T / < - π ( N ( kg :-; 6- ]< \ < ( Pa / ( J kg K z ( K ( m s U - UF V ( m s U - ( m s U - P V k ( s - (/ F m C (mv % -6 E F T I J k n m mɺ M p g T u u w γ µ [$($? ^- _ G :-;?o < G S TJ _] G _ G z O;L P ] cm j M _ \] V- j ] < G S G S ] - _ H / cm 9 : Z [ m S / _ M? H I ] :@ M [ ( H _ - - E - G J _ H J 6 Dm M?o IU a U - HF J _ - E : H f _ \ \E M r G / J _ - : D J Q 6 - ] I X: < 6Q \ x Z ( j : D J _] T^ I :S < 6Q < 6Q _:S G F < < 6Q G F ^ Z < 6Q G F w ] Œ Q G _ - [] : < @: Z [ _] x S < 6Q w j 6/?:U G < 6Q F + %* N$ ( E 6 +-'$( IZO - < [] (> - <? V H > _k H F- MPD 6/ O;L G U - ' MHD DEF IJ > ( ] 9 V- HLLE DZ :-; < U - 6
6 (j + 6- Dm UF < P < h i r z ( - [] Gallimor D, nod Powr Dposiion in Coaxial MPD Thrusrs, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, 99 [] Sabr J, nod Powr in a Quasi-Sady MPD Thrusr, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, 9 [] Kuboa K, Funaki I, and Okuno Y, Numrical Sudy on Elcrod Modl for Plasma Simulaion of MPD Thrusr, Th nd Inrnaional Elcric Propulsion Confrnc, Wisbadn, Grmany, IEPC--, [] oyl M J, cclraion Procsss in h Quasi-Sady Magnoplasmadynamic Discharg, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, 9 [] Sankaran K, Simulaion of Plasma Flows in Slf-Fild Lornz Forc cclraors, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, [6] hangar M, Ebrahimi, Shams M, Numrical simulaion of non-quilibrium plasma flow in a cylindrical MPD hrusr using a high-ordr flux-diffrnc spliing mhod, ca sronauica, Vol, No, PP 9-, IJ Z-U F- ƒ: : s 6 [] :-; < a@/ F^ 9 MHD DEF 9 ] 6/ > -?Z ( PFS 6/ [] Lopz L C, n Inroducion o Plasma Physics and is Spac pplicaions, Lcur Nos, Escula d Ingniría ronáuica y dl Espacio, Univrsidad Poliécnica d Madrid, [9] lbroni, Cahod Procsss in MPD Thrusrs, PhD Thsis, Facola di Inggnria, Univrsia dgli Sudi di Pisa, [] Michnr M, and Krugr C H, Parially Ionizd Gass, Publishd by Willy-Inrscinc, ISN: --6-, 9 [] Uribarri L, and Chouiri E Y, Th Ons of Volag Hash and is laionship o nod Spos in Magnoplasmadynamic Thrusrs, Prsnd a h 9 h Inrnaional Elcric Propulsion Confrnc, Princon Univrsiy, IEPC--, [] Diningr W D, Chopra, Piviroo T J, Goodfllow K D, and arn J W, -KW mmonia rcj Tchnology, Final por, JPL Publicaion 9-, Scion, 99 [] Diaman K D, Chouiri E Y, and Jahn G, Spo Mod Transiion and h nod Fall of Pulsd Magnoplasmadynamic Thrusrs, Journal of Propulsion and Powr, Vol, No 6, PP 6-, 99 [] rucknr P, Spcroscopic Su of h Exhaus Plum of a Quasi-Sady MPD cclraor, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, 9 [] Chouiri E Y, and Zimr J K, Quasi-Sady Magnoplasmadynamic Thrusr Prformanc Daabas, Journal of Propulsion and Powr, Vol, No, PP 96-96, [6] Jahn G, Physics of Elcric Propulsion, McGraw-Hill, 96 [] Obrh C, nod Phnomna in High-Currn Dischargs, PhD Thsis, Princon Univrsiy, Princon, Nw Jrsy, 9 [] Mokrov M S, and aizr Y P, On h Mchanism of h Ngaiv Diffrnial sisanc of a Townsnd Discharg, Plasma Sourcs Scinc and Tchnology, Vol, No, PP, [9] z W, and Hockr K H, Thori ds nodnfall I, Zischrif für Naurforschung, Vol 9a, PP -, 9 [] Hockr K H, and z W, Thori ds nodnfall II, Zischrif für Naurforschung, Vol a, PP 6-, 9