Summary
We have considered the optimal conditions for the determinations of relaxation spectra. The numerical process should be based on a well-posted method and should be free of artificial stability conditions. Such artificial conditions are those which restrict or prescribe the shape of the spectra. From the practical point of view we found that simple numerical processes which do not contain matrix inversion are convenient.
Similar content being viewed by others
Abbreviations
- a ij :
-
elements of matrixt
- b ij :
-
elements of matrixβ
- k ij :
-
elements of matrix ϰ
- m ij :
-
elements of matrixℳ
- s :
-
variable in eq. [1]
- v i :
-
elements of matrixV
- x :
-
variable in eq. [1]
- γ :
-
smoothing factor
- λ :
-
matrix eigenvalue
- v :
-
defined by eq. [6]
- ϕ(x) :
-
experimental measured function, defined by eq. [1]
- F(s) :
-
defined by eq. [1]
- F * (s) :
-
defined by eq. [13]
- G′(x) :
-
real part of dynamic modulus
- H 3 (x) :
-
thirdSchwarzl-Staverman approximation of relaxation spectrum
- J(x) :
-
creep compliance
- K(x, s) :
-
kernel of integral in eq. [1]
- \(\bar L(x)\) :
-
secondSchwarzl-Staverman approximation of retardation spectrum
- R 1 :
-
cumulative relative error of approximation of relaxation spectrum; defined by eq. [3]
- R 2 :
-
cumulative relative error of spectral relaxation function; defined by eq. [4]
References
Alfrey, T. andP. Doty, J. Applied Phys.16, 700 (1945).
Andrews, R. D., Ind. Eng. Chem.44, 707 (1952).
Ferry, J. D. andM. L. Williams, J. Colloid Sci.14, 347 (1952).
Schwarzl, F. andA. J. Staverman, Appl. Sci. Res.A4, 127 (1953).
Okano, M., Busseiron Kenkyu3, 493 (1958).
Fujita, H., J. Applied Phys.29, 943 (1958).
Ninomiya, K. andJ. D. Ferry, J. Colloid Sci.14, 36 (1959).
Tschoegel, N. W., Rheol. Acta10, 582–600 (1971).
Tobolsky, A. V. andK. Murakami, J. Polym. Sci.40, 443 (1959).
Gradowczyk, M. H. andF. Moavenzadeh, Trans. Soc. Rheol.13, 173 (1969).
Clauser, J. F. andW. G. Knauss, Trans. Soc. Rheol.10, 191 (1966).
Twomey, S., J. Assn. Computing Machinery10 (January 1963).
Phillips, D. L., J. Assn. Computing Machinery9 (January 1962).
Tanner, R. I. andG. Williams, Trans. Soc. Rheol.14, 19 (1970).
Burger, H. C. andP. H. Van Cittert, Physik79, 722 (1932).
Hopkins, J. L., J. Polymer Sci.50, 59 (1961).
Roesler, F. C. andW. A. Twyman, Proc. Phys. Soc.B68, 97 (1955).
Hlaváček, B. andV. Kotrba, Rheol. Acta6, 288 (1967).
Hlaváček, B., Rheol. Acta,7, 225 (1968).
Hlaváček, B. andV. Sinevič, Rheol. Acta9, 312 (1970).
Hlaváček, B. andF. A. Seyer, J. Appl. Polym. Sci.16, 423 (1972).
Todd, J. Quart. J. Mech. Appl. Math.2, 469 (1949).
Von Neumann, J. andH. H. Goldstine, Bull. Amer. Math. Soc.53, 1021 (1947).
Stanislav, J. andB. Hlaváček (to be published).
Author information
Authors and Affiliations
Additional information
With 2 figures and 3 tables
Rights and permissions
About this article
Cite this article
Stanislav, J., Seyer, F.A. & Hlaváček, B. Numerical determination of retardation and relaxation spectra optimalization of numerical process. Rheol Acta 13, 602–607 (1974). https://doi.org/10.1007/BF01521762
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01521762