Here we provide a physical and mathematical framework for the description of flow-driven oscillators. These oscillators, differently from frequency-driven harmonic systems, are based on countercurrent mass flows and thermal-energy exchange. We describe this class of oscillators through two countercurrent fluids separated by a heated conductive medium. We show how this configuration embeds the essential elements of harmonic oscillators, such as resonance condition, periodic orbits, and quality factor or decay time. The key advantage of recognizing flow-driven systems as oscillators lies in the possibility to engineer them according to the properties of resonant systems and utilize them to control their temperature, maximize the stored energy, or coupling them in networks. We report examples of simple configurations at their resonant condition, enhancing both thermal energy and decay time by factors larger than 10. We finally show two flow-driven oscillators coupled in series, featuring a reconfigurable internal temperature distribution, depending on the selected resonant condition.

中文翻译：

---

流驱动共振能量系统

在这里，我们提供了一个物理和数学框架来描述流驱动振荡器。这些振荡器与频率驱动的谐波系统不同，它们基于逆流质量流和热能交换。我们通过被加热的导电介质隔开的两种逆流流体来描述此类振荡器。我们将展示这种配置如何嵌入谐波振荡器的基本元素，例如谐振条件，周期性轨道以及品质因数或衰减时间。将流驱动系统识别为振荡器的主要优势在于可以根据谐振系统的特性对其进行工程设计，并利用它们来控制其温度，最大化存储的能量或将它们耦合到网络中。我们报告了在共振条件下的简单配置示例，