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Mesh Used (mesh + used)
Selected AbstractsTowards automatic structured multiblock mesh generation using improved transfinite interpolationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2008C. B. AllenArticle first published online: 4 OCT 200 Abstract The quality of any numerical flowfield solution is inextricably linked to the quality of the mesh used. It is normally accepted that structured meshes are of higher quality than unstructured meshes, but are much more difficult to generate and, furthermore, for complex topologies a multiblock approach is required. This is the most resource-intensive approach to mesh generation, since block structures, mesh point distributions, etc., need to be defined before the generation process, and so is seldom used in an industrial design loop, particularly where a novice user may be involved. This paper considers and presents two significant advances in multiblock mesh generation: the development of a fast, robust, and improved quality interpolation-based generation scheme and a fully automatic multiblock optimization and generation method. A volume generation technique is presented based on a form of transfinite interpolation, but modified to include improved orthogonality and spacing control and, more significantly, an aspect ratio-based smoothing algorithm that removes grid crossover and results in smooth meshes even for discontinuous boundary distributions. A fully automatic multiblock generation scheme is also presented, which only requires surface patch(es) and a target number of mesh cells. Hence, all user input is removed from the process, and a novice user is able to obtain a high-quality mesh in a few minutes. It also means the code can be run in batch mode, or called as an external function, and so is ideal for incorporation into a design or optimization loop. To demonstrate the power and efficiency of the code, multiblock meshes of up to 256 million cells are presented for wings and rotors in hover and forward flight. Copyright © 2007 John Wiley & Sons, Ltd. [source] GradH-Correction: guaranteed sizing gradation in multi-patch parametric surface meshingINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2005Stefano Pippa Abstract In this paper a new method, called GradH-Correction, for the generation of multi-patch parametric surface meshes with controlled sizing gradation is presented. Such gradation is obtained performing a correction on the size values located on the vertices of the background mesh used to define the control space that governs the meshing process. In the presence of a multi-patch surface, like shells of BREP solids, the proposed algorithm manages the whole composite surface simultaneously and as a unique entity. Sizing information can spread from a patch to its adjacent ones and the resulting size gradation is independent from the surface partitioning. Theoretical considerations lead to the assertion that, given a parameter ,, after performing a GradH-Correction of level , over the control space, the unit mesh constructed using the corrected control space is a mesh of gradation , in the real space (target space). This means that the length ratio of any two adjacent edges of the mesh is bounded between 1/, and ,. Numerical results show that meshes generated from corrected control spaces are of high quality and good gradation also when the background mesh has poor quality. However, due to mesh generator imprecision and theoretical limitations, guaranteed gradation is achieved only for the sizing specifications and not for the generated mesh. Copyright © 2004 John Wiley & Sons, Ltd. [source] Surgical mesh used for an inguinal herniorrhaphy acting as a nidus for a bladder calculusINTERNATIONAL JOURNAL OF UROLOGY, Issue 9 2006TRU NGO Abstract, We describe an unusual case of surgical mesh used in laparoscopic inguinal herniorrhaphy acting as a nidus for a bladder calculus. [source] Polypropylene mesh used for adjuvant reconstructive surgical treatment of advanced pelvic organ prolapseJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2010Tzu-Yin Lin Abstract Aim:, To elucidate the outcome of transvaginal pelvic reconstructive surgery using polypropylene mesh (Gynemesh; Ethicon, Somerville, NJ, USA) for patients with pelvic organ prolapse (POP) stage III or IV. Methods:, Thirty-nine patients who underwent transvaginal pelvic reconstructive surgery from September 2004 through December 2005 were collected and analyzed. All patients underwent pelvic reconstructive surgery with anterior and posterior colporrhaphy with Gynemesh reinforcement. Results:, The average age of the patients was 64.1 years and average parity was 3.9. Thirty-four patients had Pelvic Organ Prolapse Quantification (POP-Q) stage 0, four patients had stage I, and one patient had stage II at a median follow-up time of 18 months postoperatively. The success rate was 97.4%. Only one patient (2.6%) had recurrent genital prolapse (stage II) postoperatively. Quality of life was evaluated before and after the operations. The mean scores on the Urinary Distress Inventory-6 (UDI-6) and Incontinence Impact Questionnaire-7 (IIQ-7) were 5.0 ± 4.6 and 8.7 ± 6.2 before the operation and 3.0 ± 4.7 and 3.2 ± 5.6 after the operation, respectively (P = 0.03 and 0.01). The complication rate was 10.3 %, including one vaginal mesh erosion (2.6%), one dyspareunia (2.6%) and two prolonged bladder drainage (longer than 14 days, 5.1%). The mean duration of postoperative bladder drainage was 2.4 days and mean postoperative hospital stay was 5.1 days. Neither long-term nor major complication was identified. Conclusion:, Transvaginal pelvic reconstructive surgery with polypropylene mesh reinforcement is a safe and effective procedure for POP on 1.5 years' follow- up. It also has positive influence on quality of life. [source] | ||||||||||