{"title":"Lie symmetry and variational analysis of a blood flow model with body forces","authors":"Debendra Prasad Panda, Manoj Pandey","doi":"10.1016/j.ijnonlinmec.2025.105191","DOIUrl":null,"url":null,"abstract":"<div><div>This work presents a comprehensive analysis of a one-dimensional nonlinear blood flow model that incorporates a body force term, using both Eulerian and Lagrangian descriptions. By introducing Lagrangian coordinates, the system is reformulated as a single second-order partial differential equation derived from a variational principle. Lie symmetry analysis is performed in both coordinate systems, leading to the construction of one-dimensional optimal systems and exact invariant solutions. Variational symmetries satisfying Noether’s criterion are identified, and the associated conservation laws are obtained using Noether’s theorem. Finally, the evolution of weak discontinuity waves is investigated using an exact solution, revealing important nonlinear effects such as wave steepening and shock formation. The results highlight the role of symmetries and conservation laws in understanding wave behavior in physiological flow models.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105191"},"PeriodicalIF":2.8000,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Non-Linear Mechanics","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0020746225001799","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
This work presents a comprehensive analysis of a one-dimensional nonlinear blood flow model that incorporates a body force term, using both Eulerian and Lagrangian descriptions. By introducing Lagrangian coordinates, the system is reformulated as a single second-order partial differential equation derived from a variational principle. Lie symmetry analysis is performed in both coordinate systems, leading to the construction of one-dimensional optimal systems and exact invariant solutions. Variational symmetries satisfying Noether’s criterion are identified, and the associated conservation laws are obtained using Noether’s theorem. Finally, the evolution of weak discontinuity waves is investigated using an exact solution, revealing important nonlinear effects such as wave steepening and shock formation. The results highlight the role of symmetries and conservation laws in understanding wave behavior in physiological flow models.
期刊介绍:
The International Journal of Non-Linear Mechanics provides a specific medium for dissemination of high-quality research results in the various areas of theoretical, applied, and experimental mechanics of solids, fluids, structures, and systems where the phenomena are inherently non-linear.
The journal brings together original results in non-linear problems in elasticity, plasticity, dynamics, vibrations, wave-propagation, rheology, fluid-structure interaction systems, stability, biomechanics, micro- and nano-structures, materials, metamaterials, and in other diverse areas.
Papers may be analytical, computational or experimental in nature. Treatments of non-linear differential equations wherein solutions and properties of solutions are emphasized but physical aspects are not adequately relevant, will not be considered for possible publication. Both deterministic and stochastic approaches are fostered. Contributions pertaining to both established and emerging fields are encouraged.