DTATools — Design-Through-Analysis ToolsDTATools —— 设计—分析一体化工具

DTATools is an integrated isogeometric CAD–CAE platform. It keeps one spline model from the first sketch to the verified, optimized part: design → simulate → optimize → redesign → re-analyze, with no mesh-conversion step in between.DTATools 是一个等几何 CAD–CAE 一体化平台。从最初的草图到经过验证的优化零件，始终使用同一个样条模型：设计 → 仿真 → 优化 → 重构 → 再分析，中间无需任何网格转换。

The workflow工作流程

1 Design设计

Spline and CAD modelling with a feature tree (primitives, sketch, extrude, revolve, sweep) and STEP import. A built-in assistant connects DTATools to a large language model: you describe a part or an analysis in a sentence, and the assistant writes the design features, supports and loads. What it writes is checked and repaired before it is applied, and everything remains editable by hand.

基于特征树的样条与 CAD 建模（基本体、草图、拉伸、旋转、扫掠），支持导入 STEP。内置助手将 DTATools 与大语言模型相连：用一句话描述零件或分析，助手即可写出设计特征、约束与载荷。助手写出的内容在应用前会被检查和修复，之后仍可全部手动编辑。

2 Simulate仿真

The part is immersed in a spline background grid; cut cells are integrated separately, so no body-fitted mesh has to be generated. Body-fitted spline discretizations are available when an analysis-suitable parameterization exists, and an independent tetrahedral analysis of the same STEP solid serves as a cross-check.

零件直接浸入样条背景网格，被切割的单元单独积分，因此无需生成贴体网格。当存在分析适用参数化时也可使用贴体样条离散；同一 STEP 实体上的独立四面体分析可用于交叉验证。

3 Optimize优化

Topology optimization (minimum compliance under a volume limit) runs on the same model, with the convergence history plotted live. For shape optimization the spline control points are the design variables, so the optimized shape stays a spline.

在同一模型上进行拓扑优化（体积约束下的柔度最小化），并实时绘制收敛历史。形状优化以样条控制点为设计变量，因此优化后的形状仍然是样条。

4 Redesign重构

The optimized result is rebuilt as a watertight solid of B-spline faces, intersected with the exact design space so that holes remain exact cylinders, and written as STEP and IGES — CAD surfaces, not a triangle mesh.

优化结果被重建为由 B 样条面组成的水密实体，并与精确的设计空间求交，使孔保持为精确圆柱面，最终导出 STEP 和 IGES——得到的是 CAD 曲面，而不是三角网格。

5 Re-analyze再分析

The rebuilt part is analysed again with the same supports and loads, applied automatically, so the optimized design is verified on the geometry that is actually delivered.

重建后的零件自动沿用相同的约束与载荷再次分析，从而在最终交付的几何上验证优化设计。

Beyond structures: flow simulation不止于结构：流动仿真

The same platform handles incompressible flow. In this example the spline model is the mesh: the vessel tree consists of 56 quadratic B-spline patches (11,136 spline elements). The measured inflow, three-element Windkessel outlets and backflow stabilization are set in the application layer, and the flow is solved with equal-order splines and VMS stabilization. Against the spectral-element solver Nek5000 on the same anatomy and boundary conditions, the outlet flow split agrees within 0.35 percentage points and the mean inlet pressure within 0.26 mmHg.

同一平台也可处理不可压缩流动。在这个算例中，样条模型本身就是网格：血管树由 56 个二次 B 样条片组成（共 11,136 个样条单元）。实测入口流量、三元件 Windkessel 出口和回流稳定化都在应用层设置，流动采用等阶样条与 VMS 稳定化求解。在相同解剖模型和边界条件下与谱元求解器 Nek5000 对比，各出口流量分配相差不超过 0.35 个百分点，入口平均压力相差 0.26 mmHg。

Methods behind it背后的方法