前人应用线性稳定性分析揭示了产生于竖直加热壁面的自然对流边界层的部分不稳定性特征。申请人应用直接稳定性分析，通过完全求解含有扰动源项的控制方程，近一步揭示了普朗特数Pr=7、恒温壁面产生的自然对流边界层的多种不稳定性特征，如频谱过滤特性、共振特性等。基于申请人前期揭示的单一边界层的共振特性，该项目将创新性地构建并研究双边界层自主式共振条件下的不稳定性特征。该项目拟从三方面开展Pr=0.7的双自然对流边界层的自主式共振特征及其机理的研究：1、Pr=0.7的单一自然对流边界层不稳定性特征的研究；2、单一边界层非自主式共振特征及其机理的研究；3、双自然对流边界层自主式共振特征及其机理的研究。该项目先研究单一边界层的不稳定性特征，再创新性地研究双边界层相互作用时的不稳定性及自主式共振机理，为探索多边界层及复杂羽流控制提供新的方法和理论依据。

Researchers using linear stability analyses have revealed instability characteristics of natural convection boundary layers adjacent to a heated vertical surface. A recent direct stability analysis conducted by the applicant of this project, which solved full governing equations with disturbance function, revealed the resonance characteristics of natural convection boundary layers at Pr=7 induced by an isothermal surface, such as the frequency filtering effect and the resonance characteristics. On the basis of these resonance characteristics of a single boundary layer, the present project aims to create and study the instability characteristics of the self-induced resonance of double natural convection boundary layers. The present project plans to study the characteristics and mechanism of the self-induced resonance of double natural convection boundary layers via three stages. Firstly, the instability characteristics of a single natural convection boundary layer of Pr=0.7 will be studied. Secondly, the characteristics and mechanism of the numerically-induced resonance of the single boundary layer will be examined. Thirdly, the characteristics and mechanism of the self-induced resonance of double natural convection boundary layers will be investigated. This project starts with the instability characteristics of a single boundary layer, and then the project extends to the instability and resonance characteristics of two interacting boundary layers, which provides a new approach and theoretical basis for the control of multiple boundary layers and complex plumes.