基于计算流体力学方法的二级及以上分支的动脉血液流场分析
Arterial Blood Flow Field Analysis of Secondary and above Branches Based on Computational Fluid Dynamics Methods

目的：医学方面不能直接测量肺部血管的血流动力学参数，具有一定误差，且计算流体力学模拟肺动脉手术前后的流场具有直观方便的优势，模拟得到的流场参数能够为医学对于肺叶切除手术的改进与患者康复的方法提供依据和思路，因此本文通过对经过处理CT影像图后的左肺上叶切除手术的患者进行血流动力学的模拟，对左肺上叶切除手术的患者流速与压强在手术前后的变化进行分析。方法：本研究取一名进行了左肺上叶切除手术患者在手术前后的肺动脉的CT影像图，应用医学软件对临床获得的CT影像图进行处理，获得患者在手术前后包含肺动脉主脉、左右支脉及细微分支的三维模型，通过计算流体力学软件进行网格处理，数据计算及后处理后，得到患者在手术前后的肺动脉流场及压强分布云图，并进行分析。结果：模拟出左肺上叶切除手术前后的肺动脉流场及压强分布云图，分析了流速与压强在手术前后的分布情况。结论：手术后肺动脉总体流速明显降低，且对比肺动脉左右支脉，肺动脉左支脉流速降低明显增多；壁面压强总体增大，达到峰值区域增多，肺动脉左支脉压强增大，但右支脉压强变化不明显且二级分支后的血管分支处压强相较术前降低，本研究为医学方面对左肺上叶切除手术的改进与研究提供了思路。
Purpose: In medicine, hemodynamic parameters of pulmonary vessels cannot be measured directly, and there is a certain error. Computational fluid dynamics simulation of the flow field before and after pulmonary artery surgery has the advantage of being intuitive and convenient. The simulated flow field parameters can provide medical guidance for lobectomy surgery. To provide basis and ideas for improving methods of patient rehabilitation, this article simulates hemodynamics in patients undergoing left upper lobectomy after processing CT images, and analyzes the flow velocity and pressure of patients undergoing left upper lobectomy. Changes before and after surgery were analyzed. Methods: This study took the CT images of the pulmonary artery of a patient who underwent left upper lobectomy before and after the operation, and used medical software to process the clinically obtained CT impact images to obtain the patient’s pulmonary artery main artery, left and right branches before and after the operation. The three-dimensional model of the patient’s pulmonary artery flow field and pressure distribution before and after surgery is obtained through grid processing using computational fluid dynamics software. After data calculation and post-processing, the patient’s pulmonary artery flow field and pressure distribution cloud map before and after surgery are obtained and analyzed. Results: The pulmonary artery flow field and pressure distribution cloud diagram before and after left upper lobectomy were simulated, and the distribution of flow velocity and pressure before and after surgery were analyzed. Conclusion: After surgery, the overall flow velocity of the pulmonary artery significantly decreased, and compared with the left and right branches of the pulmonary artery, the flow velocity of the left branch decreased more significantly. The wall pressure increased in general, and the number of areas reaching the peak value increased. The pressure of the left branch of the pulmonary artery increased, but the change of pressure in the right branch was not