Physics basis for a tokamak fusion power plant

Jardin, S.C.; Bathke, C.G.; Ehst, D.A.; Kaye, S. M.; Kessel, C.; Lee, B.J.; Mau, T. K.; Menard, J.E.; Miller, R.L.; Najmabadi, F.

doi:10.1016/s0920-3796(00)00166-6

Cited by 20 publications

(10 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The design challenge can be summarized by considering the governing equations (e.g. [5]) for tokamak fusion. The fusion power P fusion (and neutron) loading over the wall/blanket surface area S at fixed tokamak aspect ratio and shape is given by…”

Section: Advantages Of High Magnetic Field For Fusion Developmentmentioning

confidence: 99%

Smaller & Sooner: Exploiting High Magnetic Fields from New Superconductors for a More Attractive Fusion Energy Development Path

et al. 2016

View full text Add to dashboard Cite

The current fusion energy development path, based on large volume moderate magnetic B field devices is proving to be slow and expensive. A modest development effort in exploiting new superconductor magnet technology development, and accompanying plasma physics research at high-B, could open up a viable and attractive path for fusion energy development. This path would feature smaller volume, fusion capable devices that could be built more quickly than low-to-moderate field designs based on conventional superconductors. Fusion's worldwide development could be accelerated by using several small, flexible devices rather than relying solely on a single, very large device. These would be used to obtain the acknowledged science and technology knowledge necessary for fusion energy beyond achievement of high gain. Such a scenario would also permit the testing of multiple confinement configurations while distributing technical and scientific risk among smaller devices. Higher field and small size also allows operation away from wellknown operational limits for plasma pressure, density and current. The advantages of this path have been long recognized-earlier US plans for burning plasma experiments (compact ignition tokamak, burning plasma experiment, fusion ignition research experiment) featured compact high-field designs, but these were necessarily pulsed due to the use of copper coils. Underpinning this new approach is the recent industrial maturity of high-temperature, highfield superconductor tapes that would offer a truly ''game changing'' opportunity for magnetic fusion when developed into large-scale coils. The superconductor tape form and higher operating temperatures also open up the possibility of demountable superconducting magnets in a fusion system, providing a modularity that vastly improves simplicity in the construction, maintenance, and upgrade of the coils and the internal nuclear engineering components required for fusion's development. Our conclusion is that while tradeoffs exist in design choices, for example coil, cost and stress limits versus size, the potential physics and technology advantages of high-field superconductors are attractive and they should be vigorously pursued for magnetic fusion's development.

show abstract

Section: Advantages Of High Magnetic Field For Fusion Developmentmentioning

confidence: 99%

Smaller & Sooner: Exploiting High Magnetic Fields from New Superconductors for a More Attractive Fusion Energy Development Path

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The samples were measured in transmission through the diameter using a 6 Â 6 Â 2 mm 3 gauge volume [8] . The center 2u-angle of the 2D 3 He-detector window (256 Â 256 pix, 300 Â 300 mm 2 ) was set to %86.58 recording Cu {3 1 1}, {2 2 2}, and W {2 2 0} reflections simultaneously.…”

Section: Neutron Diffractionmentioning

confidence: 99%

“…A plasma facing tungsten plate is attached to a CuCrZr heat sink cooled by H 2 O, He or LiPd, dependent on the type of the cooling system. CTE mismatch stresses at the interface may lead to delamination during pulsed operation, [3] which has to be avoided to achieve a good long term stability of the heat sink. Composites with high thermal conductivity and an intermediate CTE are applied as interlayer to reduce the internal stresses in the component under service conditions.…”

Section: Introductionmentioning

confidence: 99%

Thermal Cycling Stresses in W‐Monofilament Reinforced Copper

et al. 2011

View full text Add to dashboard Cite

New materials have to be developed for fusion reactor systems to withstand the high thermal load and heavy irradiation under service conditions. The divertor element collects the residuals of the nuclear reaction and withdraws heat from the reaction chamber into a heat sink. A thermal flux of ≈20 W mK−1 can be expected in such components. A plasma facing W plate is attached to a CuCrZr heat sink suffering CTE mismatch stresses at the interface due to pulsed operation required for the Tokamak reactor design. Fiber reinforced metal matrix composites are applied as an interlayer to reduce macroscopic interfacial stresses in these components. W‐wire reinforced copper is a promising material for this application due to a good fiber‐matrix bonding strength which is further increased by surface etching or graded interface designs. Thermal stresses in between the matrix and the wires are responsible for thermal fatigue damage within the constituents and at their interface. Neutron and synchrotron diffraction was performed in situ during thermal cycling to determine the micro stress amplitudes and their changes under simulated service conditions.

show abstract

“…While 7 MW/m 2 may certainly be possible, ARIES-AT blanket performance studies have shown maximum power loading of only 4.8 MW/m 2 on a silicon carbide (SiC) blanket [13]. Given this, it would not be prudent to let PF/AS exceed ~ 5 MW/m 2 [12]. Figure 5.15 shows the effect of varying PF/AS on the minimum R. The allowable area in the [R,q*] plane shifts to lower q* when PF/AS increases from 5 MW/m 2 to 7 MW/m 2 .…”

Section: Blanket Fusion Power Density Pf/asmentioning

confidence: 99%

“…where frad is the ratio of radiative power Prad to input power (P. + Paux) [12]. For the L-H transition to occur, P 0 i must be greater than the L-H transition power PL-H. As long as…”

Section: Radiative Powermentioning

confidence: 99%

A fission-fusion hybrid reactor in steady-state L-mode tokamak configuration with natural uranium

Reed¹,

Parker²,

Forget³

2012

AIP Conference Proceedings

View full text Add to dashboard Cite

The most prevalent criticism of fission-fusion hybrids is simply that they are too exotic -that they would exacerbate the challenges of both fission and fusion. This is not really true. Intriguingly, hybrids could actually be more viable than stand-alone fusion reactors while mitigating many challenges of fission. This work develops a conceptual design for a fission-fusion hybrid reactor in steady-state L-mode tokamak configuration with a subcritical natural or depleted uranium pebble bed blanket. A liquid lithiumlead alloy breeds enough tritium to replenish that consumed by the D-T fusion reaction. Subcritical operation could obviate the most challenging fuel cycle aspects of fission. The fission blanket augments the fusion power such that the fusion core itself need not have a high power gain, thus allowing for fully non-inductive (steady-state) low confinement mode (L-mode) operation at relatively small physical dimensions.A neutron transport Monte Carlo code models the natural uranium fission blanket. Maximizing the fission power while breeding sufficient tritium allows for the selection of an optimal set of blanket parameters, which yields a maximum prudent fission power gain of 7.7.A 0-D tokamak model suffices to analyze approximate tokamak operating conditions. If the definition of a "reactor" is a device with a total power gain of 40, then this fission blanket would allow the fusion component of a hybrid reactor with the same dimensions as ITER to operate in steady-state L-mode very comfortably with a fusion power gain of 6.7 and a thermal fusion power of 2.1 GW. Taking this further can determine the approximate minimum scale for a steady-state L-mode tokamak hybrid reactor, which is a major radius of 5.2 in and an aspect ratio of 2.8. This minimum scale device operates barely within the steady-state L-mode realm with a thermal fusion power of 1.7 GW. This hybrid, with its very fast neutron spectrum, could be superior to pure fission reactors in terms of breeding fissile fuel and transmuting deleterious fission products. It could operate either as a breeder, producing fuel for pure fission reactors from natural or depleted uranium, or as a deep burner, fissioning heavy metal and transmuting waste with a cycle time of decades. Despite a plethora of potential functions, its primary Mark Reedmission is deemed to be that of a deep burner producing baseload commercial power with a once-through fuel cycle. Although hybrids are often purported a priori to pose an elevated proliferation risk, this reactor breeds plutonium that could actually be more proliferation-resistant than that bred by fast reactors. Furthermore, a novel method (the "variable fixed source method") can maintain constant total hybrid power output as burnup proceeds by varying the neutron source strength.As for engineering feasibility, basic thermal hydraulic analysis demonstrates that pressurized helium could cool the pebble bed fission blanket with a flow rate below 10 m/s. The Brayton cycle thermal efficiency is 41%.This device is d...

show abstract

Physics basis for a tokamak fusion power plant

Cited by 20 publications

References 33 publications

Smaller & Sooner: Exploiting High Magnetic Fields from New Superconductors for a More Attractive Fusion Energy Development Path

Smaller & Sooner: Exploiting High Magnetic Fields from New Superconductors for a More Attractive Fusion Energy Development Path

Thermal Cycling Stresses in W‐Monofilament Reinforced Copper

A fission-fusion hybrid reactor in steady-state L-mode tokamak configuration with natural uranium

Contact Info

Product

Resources

About