The investigation on the behaviour of nuclear fuels under thermal loads representative of RIA (Reactivity Initiated Accident) conditions in nuclear reactors is a significant challenge. In this work we introduce a new concept of a laboratory experiment relying on high power lasers to reproduce the temperature gradients experienced by nuclear fuel pellets during such events. The concept is experimentally demonstrated on UO₂ samples, supported with numerical simulations to estimate the temperature gradients within the samples. This is a first step in the perspective of applying the technique on irradiated fuels.

中文翻译：

---

用激光远程加热模拟反应性引发的核燃料事故热瞬变

在代表核反应堆的RIA（反应性事故）条件的热负荷下，对核燃料行为的研究是一项重大挑战。在这项工作中，我们引入了一种实验室实验的新概念，该实验依靠高功率激光器来再现核燃料芯块在此类事件中所经历的温度梯度。该概念已在UO ₂样品上进行了实验验证，并通过数值模拟来支持，以估算样品内的温度梯度。从将技术应用于辐照燃料的角度来看，这是第一步。