Forced Convection Heat Transfer in Unconventional Geothermal Systems: Numerical Investigation of Complex Flow Processes near Magmatic Chambers

最近对前沿增强型地热系统（EGS）的研究强调，需要更好地了解相关的热交换和流体动力学，以便在非常规井设计和最佳性能的定义之间实现融合。虽然对岩浆房内的对流和混合以及天然地下水系统中的热液循环进行了广泛的研究，但对岩浆到水的热传递、超临界/过热流体的行为以及岩浆房附近的刺激和人工注入引发的对流力的了解有限。相变引起的多相流现象进一步改变了对流热输运。从传导与常规地热系统之间的根本区别开始，本博士研究将重点关注稳态和瞬态传热过程以及与岩浆室附近自由对流和强制对流相关的流体动力学。考虑到文献中已经实施或提出的各种深层地热解决方案，将定义不同的场景。数值工具将用于复制不同火山地点的设置，其中相关参数将从公共领域的文献中提取。本博士的研究成果将有助于重新评估全球地热资源基础，并旨在改善目前对自由对流和强迫对流结合下岩浆到水的热量传递的理解

Recent research into frontier Enhanced Geothermal Systems (EGS) has highlighted the need to better understand the associated heat exchange and fluid dynamics to converge between unconventional well designs and the definition of where their performance would be best. Whilst convection and mixing within magma chambers and hydrothermal circulation in natural groundwater systems have been extensively investigated, there is limited understanding of the heat transfer from magma to water, the behaviour of supercritical/superheated fluids and the convective forces triggered by stimulation and artificial injection near magmatic chambers. Convective heat transport is further modified by multiphase flow phenomena induced by phase change.Beginning with the fundamental differences between conduction- vs. convention-dominated geothermal systems, this PhD research will focus on the steady-state and transient heat transfer processes and fluid dynamics associated with free and forced convection near magmatic chambers.Different scenarios will be defined considering the various deep geothermal solutions that have already been implemented or proposed in the literature. Numerical tools will be used to reproduce the settings from different volcano sites, where relevant parameters will be extracted from the literature available in the public domain.The outcome of this PhD will contribute to re-evaluating the geothermal resource base worldwide and aims to improve the current understanding of heat transfer from magma to water under a combination of free and forced convection