Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 07, 2019 - November 08, 2019
Urinary stones are calcium oxalate stones in the urinary tract. According to the 2005 national survey, the lifetime prevalence of urinary stones is 15.1% for Japanese men and 6.8% for women. In addition, 96% of the whole are upper urinary tract stones such as kidney stones. Small stones are excreted in the urine without feeling great pain in the process of excreting, but when they become large, natural excretory becomes difficult and it causes severe pain when it descends into a narrow ureter. Therefore, it is desirable to establish a treatment that can be discharged before growing. However, the mechanism of the flow around kidney stones from the upper urinary tract has not been fully investigated, and confirmation by follow-up observation is also difficult. Furthermore, the natural excretion can be difficult from the lower kidney calix because of the gravity. We analyzed flows around a stone by numerical simulation using immersed boundary method. First, the numerical results and the actual experiment were compared with the free fall sphere. As a result, accuracy of the numerical simulation was confirmed. Furthermore, the lower kidney calix model was created based on medical computed tomography images, and the flow of stones was analyzed by numerical simulation.