A conceptual design of the calorimeter for the Neutral Beam Injector (NBI) of the Divertor Tokamak Test facility (DTT, a new tokamak whose construction is starting in Frascati, Italy) has been developed. The DTT NBI calorimeter features two beam stopping panels made of CuCrZr cooled by pressurized water flowing through deep drilled cooling channels with twisted tape insertions. The proposed design is based primarily on the expected beam power distribution of DTT NBI, thermal-hydraulic factors (maximum temperature of the structure and coolant, pressure drop) and geometrical constraints (beam cross-section, panel inclination angle, available space for the calorimeter, etc.). Main design choices are made on the reduced model, representing a section of the panel with a single cooling channel. Detailed computational fluid dynamics (CFD) simulations of several designs were performed, leading to an optimized design in terms of minimizing the structure and coolant temperatures while respecting the operating conditions, allowed pressure drop in the cooling loop and overall space constraints.

The mechanical response of the calorimeter structures, in terms of deformations and stresses, has been also analysed for the optimized design. To obtain realistic results, the whole panel (not only the reduced section of it) with appropriate boundary conditions has been considered. To simulate the temperature distribution over the whole panel, a simplified strategy using only the solid domain was developed. Before applying it on the whole panel, it was verified on the reduced model. The follow-up thermo-mechanical simulation of the whole panel use the heat transfer coefficient on the cooling channel interface that has been previously calculated from the accurate fluid-solid CFD simulation of the reduced model. It has been shown that the thermal loads induced by the beam neutral particles dominate the deformations and stresses in the calorimeter.

已经开发了分流器托卡马克测试设备（DTT，这是一种新的托卡马克，正在意大利的弗拉斯卡蒂开始建造）的中性束注入器（NBI）量热计的概念设计。DTT NBI量热仪具有两个由CuCrZr制成的挡光板，由加压水冷却，这些水流经带有扭曲带插入物的深孔冷却通道。拟议的设计主要基于DTT NBI的预期束功率分布，热工液压因数（结构和冷却液的最高温度，压降）和几何约束（束横截面，面板倾斜角，量热仪的可用空间） ， ETC。）。主要设计选择是在简化型号上做出的，该型号代表面板上具有单个冷却通道的一部分。

量热计结构在变形和应力方面的机械响应也已进行了分析，以进行优化设计。为了获得现实的结果，考虑了具有适当边界条件的整个面板（不仅是面板的缩小部分）。为了模拟整个面板上的温度分布，开发了一种仅使用固体区域的简化策略。在将其应用于整个面板之前，已在简化模型上进行了验证。整个面板的后续热力学模拟使用冷却通道界面上的传热系数，该系数是先前根据精简模型的精确流固CFD模拟计算得出的。已经表明，由束中性粒子引起的热负荷支配着热量计中的变形和应力。