Solution Manual for Rocket Propulsion, 1st Edition by Stephen D. Heister, 9781108422277, Covering Chapters 1-13 Includes Rationales 2

16.512,bRocketbPropulsionbProf
.bManuelbMartinez-
SanchezbLectureb1:bIntroduc
tion



TypesbofbRocketsb(Engines)


- Dependingbonbgasbaccelerationbmechanism/forcebonbvehiclebmechanism.

“Thermal”
GasbpushesbdirectlybonbwallsbbybPb(pressure)bfor
cesbNozzlebacceleratesbgasbbybPbforces
(mostblargebrockets,bchem,bnuclear,bsomebelectric…)

→
Electrostatic Ionsbacceleratedbby Eb field
(a) Electrostaticbforceb(push)bonbelectrodes
(Ionbengines) →
(b) Forceb(push)bonbmagneticbcoilsbthroughbgasb j
(Hallbthrusters)
–→
Electromagnetic Gasbacceleratedbby jbbBb forces
Forceb(push)bonbcoilsborbconductorsb(MP
Dbthrusters,bPPT’s)

16.512bconcentratesbonbThermal


- Dependingbonbenergybsource:


SolidbPropellant

Chemicalb(alwaysb“thermal”) LiquidbPropellant Monopropellant
Bipropellant

Hybrid

Nuclearb(Thermal)
Nuclearb(Electric)
canbbebThermal,bESborbEMb
Solarb(Thermal)
Solarb(Electric) canbbebThermal,bESborbEM

16.512bdealsbmostlybwithbChemical.


- DependingbonbThrustblevelb(perbunitbmass)

- Highbthrustb(bb 1g)bforblaunch,bfastbspacebmaneuveringb(16.512)
- Lowbthrustb(10-5b–b10-2bg)bforbefficientbin-spacebmaneuversb(16.522)
16.512,bRocketbPropulsionbPro Lectureb1
f.bManuelbMartinez-Sanchez Pageb1bofb3

,PerformancebMeasures


SpecificbImpulse
Ispb =
F
ṁbg (orbcb=b
F
ṁ )
(sec) (m/sec)


Dominantbforbchem.bRockets,brangeb200-
500bsecbTrade-offbvs.bmassbforbEP,brangeb500-
6000bsec


thb =b b Jetbkineticbpower
Thermalbinputbpower
ThermalbEfficiency

(ThermalbRockets)
Alsobforbelectricalbthrusters

Powerbtobjet
bInputbelectricalbp
 b=b
ower
~b30-80b%
th
Verybclosebtob100%binbchem.b(non-issue)bimportantbinbsolarbthermalb(60-
80%)belectrothermal,betc.


Thrust/weightb F/W

Veryblargeb~b(20-
100)bforbChem.bMediumb(5-
20)bforbNuclear
Veryblowb(~10-3)bforb(Solar,bEP,bpowerblimited)


Othersb(designbselectionbfactors)

- “Life”,bmostbmeaningfulbinbtotalbimpulsebcapacity
- Re-startbcapability
- Throttleability
- Dispersion
- Cost




RocketbSelectionbGuideb(bybmission)


16.512,bRocketbPropulsionbPro Lectureb1
f.bManuelbMartinez-Sanchez Pageb2bofb3

, 1) Non-Spacebmissions
RocketbTypebAtmospheric/I
onosphericbSounding SolidbPropellant,b1-
b

4bstagesbTacticalbMissile SolidbProp.,b1-2bstages
Medium-LongbRangebMissiles SolidborbLiquidbProp.,b2-
3bstagesb(verybhighbaccel
eration)

2) Launchbtobspace
Solid,bliquidborbcombina
tions,b2-4bstagesb(2-4g)
Possible:bhybrid,b2-4bstages


3) Impulsiveb∆Vbinbspace
SmallbSolidbProp.b(Apogeeb
(time-criticalbmaneuvers, kick,betc)
b

energybchangebfrombellipticborbits, Bi-
b

propellantb(storable)bplanebchangebfrombellipticborbits,
liquids,bMonopropellant
non-fuel-limitedbsituations...) (storable)bliquids,
∆Vb≤b1000bm/s Future:bNuclearbthermal

4) Low-Thrustb∆Vbinbspace
(Mass-limitedbmissionsb∆Vb≥b2000bm/s Solar-electricbsystems:
nonbtime-criticalbmissions,
Arcjetsb(abbitbfaster,blessbIsp)b
small,bcontinuousborbitbcorrections
Hall,bIonb(slower,bhigherbIsp)b
near-circularborbits...) PPTb(precisionbmaneuvers)
Nuclear-
electricbsystemsbDirectbs
olar-thermal




16.512,bRocketbPropulsionbPro Lectureb1
f.bManuelbMartinez-Sanchez Pageb3bofb3

, 16.512,bRocketbPropulsion,bPro
f.bManuelbMartinez-Sanchez
Lectureb2:bRocketbNozzlesbandbThrustbRoc


ketbThrustb(Thermalbrockets)




•

mb=b   u dA
Ae
b
b n e




 Pb dSxb − P dA
b e ex
=b u
b
xb(  bunb)dAe
Solidbint. Ae Ae
surfaces
•
(Tanksbincluded) dm



Note:
 PadSxb−b
s.,intb P dA
Ae
b a ebx
=b 0, sobsubtract,




 (P − P ) dS =(P
b b ab b xb
b
)
eb −bPab bdAe
xb
+b  u u dA
b
x n e

Solidbint. Ae Ae




Thrustb bF




16.512,bRocketbPropulsionbPro Lectureb2
f.bManuelbMartinez-Sanchez Pageb1bofb7