On the definition of fractional derivatives in rheology
On the definition of fractional derivatives in rheology作者机构:Department of Engineering Mechanics Tsinghua University Beijing 100084 ChinaDepartment of Physics the Chinese University of Hong Kong Hong Kong China
出 版 物:《Theoretical & Applied Mechanics Letters》 (力学快报(英文版))
年 卷 期:2011年第1卷第1期
页 面:62-65页
学科分类:07[理学] 070101[理学-基础数学] 0831[工学-生物医学工程(可授工学、理学、医学学位)] 0830[工学-环境科学与工程(可授工学、理学、农学学位)] 0707[理学-海洋科学] 0815[工学-水利工程] 0805[工学-材料科学与工程(可授工学、理学学位)] 0813[工学-建筑学] 0824[工学-船舶与海洋工程] 0802[工学-机械工程] 0836[工学-生物工程] 0814[工学-土木工程] 0825[工学-航空宇航科学与技术] 0701[理学-数学] 0801[工学-力学(可授工学、理学学位)] 0702[理学-物理学]
基 金:supported by NSFC under the grant number 10972117
主 题:fractional derivative Caputo definition Riemann-Liouville definition Scott-Blair model
摘 要:During the last two decades fractional calculus has been increasingly applied to physics, especially to *** is well known that there are obivious differences between Riemann-Liouville (R-L) definition and Caputo definition,which are the two most commonly used definitions of fractional *** multiple definitions of fractional derivatives have hindered the application of fractional calculus in *** this paper,we clarify that the R-L definition and Caputo definition are both Theologically unreasonable with the help of the mechanical analogues of the fractional element *** also find that to make them more reasonable Theologically,the lower terminals of both definitions should be put to—∞.We further prove that the R-L definition with lower terminal—∞and the Caputo definition with lower terminal—∞are equivalent in the differentiation of functions that are smooth enough and functions that have finite number of singular *** we can define the fractional derivatives in rheology as the R-L derivatives with lower terminal—∞(or,equivalently,the Caputo derivatives with lower terminal—∞) not only for steady-state processes,but also for transient processes.