Lawson Diagram For Selfsustaining Fusion Burns

Figure B.3. Lawson criterion.

Figure B.4. Generic fusion rocket geometry (from [Santarius and Logan, 1998]).

j Inptil power (not Indeed In mode!) '

Figure B.4. Generic fusion rocket geometry (from [Santarius and Logan, 1998]).

efficiency vd) or by thermal conversion (for the remaining part) with an efficiency vth into electrical power Pel = [vd/d + Vth(1 -/d)](1 - fr)(Pfus + Paux).

A certain fraction of this power must be used for auxiliary systems. If the efficiency for auxiliary power generation is vaux, such a fraction is given by Paux/vaux = FPel, with F being the re-circulating power fraction.

Figure B.5. Idealized power flow in a fusion rocket.

FPel

Figure B.5. Idealized power flow in a fusion rocket.

The fusion gain Q can then be related to F, vth, and vaux by

The waste power to be radiated to space is therefore

Prad = f (1 - Vd) + (1 - Vth)(1 - fD )](1 - fT )(Pfus + Paux) + (1 - Vaux) Paux/Vaux

If the reactor is self-sustaining (Paux = 0) then the re-circulating fraction vanishes. In practice this does not even occur for Paux = 0, since part of the electric power must feed the control system, the cryogenic system, and so on. Assuming the realistic value F = 20% and 50% for both efficiencies, values of Q in the range Q = 20-30 are necessary for efficient energy production.

From the above expressions the power available for thrust is finally

Pthrust = [(1 - F)[vDfD + Vth(1 - fD)](1 - fT) + M1 + 1/Q)Pfus (B.10)

Was this article helpful?

0 0
Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

Get My Free Ebook


Post a comment