TY - JOUR
TI - Variational principle for one-dimensional inviscid flow
AU - Liu Xian-Yong
AU - Liu Yan-Ping
AU - Wu Zeng-Wen
JN - Thermal Science
PY - 2022
VL - 26
IS - 3
SP - 2465
EP - 2469
PT - Article
AB - A family of variational principles is obtained for the 1-D inviscid flow by  Ji-Huan He's semi-inverse method. The invalidy of the Lagrange multiplier  method, e. g., the Lagrange crisis, is also discussed to eliminate  constraints of a constrained variational principle. Two approaches to the  elimination of the crisis are elucidated.