High energy gain in inertial fusion schemes requires the propagation of a thermonuclear burn wave from hot to cold fuel. We consider the problem of burn propagation when a magnetic field is orthogonal to the burn wave. Using an extended-MHD model with a magnetized α energy transport equation, we find that the magnetic field can reduce the rate of burn propagation by suppressing electron thermal conduction and α particle flux. Magnetic field transport during burn propagation is subject to competing effects: the field can be advected from cold to hot regions by ablation of cold fuel, while the Nernst and α particle flux effects transport the field from hot to cold fuel. These effects, combined with the temperature increase due to burn, can cause the electron Hall parameter to grow rapidly at the burn front. This results in the formation of a self-insulating layer between hot and cold fuel, which reduces electron thermal conductivity and α transport, increases the temperature gradient, and reduces the rate of burn propagation.

中文翻译：

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传播热核燃烧中的磁场传输

惯性聚变方案中的高能量增益需要热核燃烧波从热燃料传播到冷燃料。我们考虑磁场垂直于燃烧波时燃烧传播的问题。使用具有磁化的α能量传输方程的扩展MHD模型，我们发现磁场可以通过抑制电子热传导和α粒子通量来降低燃烧传播的速率。燃烧传播过程中的磁场传输会受到竞争效应的影响：可以通过消融冷燃料将磁场从寒冷的区域转移到高温的区域，而能斯特（Nernst）和α粒子通量效应将电场从热燃料传输到冷燃料。这些影响，再加上由于燃烧引起的温度升高，会导致电子霍尔参数在燃烧前沿迅速增长。这导致在热和冷燃料之间形成自绝缘层，这会降低电子热导率和α传输，增加温度梯度，并降低燃烧传播的速度。