• 作者： 許文翰; 黃大洲
• 作者服務機構： 國立台灣大學造船工程所; 仲琦科技股份有限公司
• 中文摘要： 本文利用以能量觀點的變分方法分析三維可壓縮無黏性的穩定流場。利用變分原理可以導出克式速度轉換式和以熵及拉氏乘子為主要變數的變分方程組。該偏微分方程組和以原始變數為主要變數的尤拉運動方程式是全等的，並可用來分析勢流和尤拉流場。利用有限元素方式將變分方程組離散。利用具有鬆性的計算程序解析流經一三維物體的低馬赫的周圍流場。
• 英文摘要： A variational method is employed for analyzing a steady three-dimensional inviscid compressibleflow-field starting with the energy formulation. The Clebsch transformation of velocity vectors and a setof governing equations using Lagrangian multipliers and entropy are derived. The resulting set of equationsis equivalent to the classic Euler equations in terms of primitive variables. This formulation provides a solu-tion scheme for solving potential and Euler equations. The resulting set of variational equations is approxi-mated by an isoparametric finite element method. The three dimensional inviscid flow over a rectangularmodel car has been analyzed by the present finite element computer code.
• 中文關鍵字： variationa; method; clebsch transformation; three-dimensional
• 英文關鍵字： --