Sensitivity of tissue freezing process on changes of time-dependent cryoprobe tip cooling rate

• Autorzy: Mochnacki B. , Siedlecki J.
• Języki publikacji: EN

Abstrakty

EN

In the paper, the problems of thermal interactions between skin tissue and a cylindrical cryoprobe tip are discussed. The cryoprobe tip temperature is time-dependent and its changes from the initial temperature to the final one and back are assumed in the form of a broken line (successive sectors correspond to cooling and heating processes or cooling and heating ones divided by a horizontal sector (a constant freezing temperature)). The aim of the considerations resolves itself in the analysis of dependences between the tip cooling (heating) rate and the course of the freezing process. To solve the problem, the direct approach of sensitivity analysis is used. The mathematical model of freezing is based on the energy equation corresponding to the 'fixed domain method' in which a parameter called 'the substitute thermal capacity' appears. The sensitivity model results from the differentiation of energy equation and boundary-initial conditions with respect to the cooling (heating) rate. At the stage of computations, the finite differences method (FDM) is used. In the final part of paper, examples of computations are presented.

Słowa kluczowe

EN

biological tissue; freezing process; tissue freezing

PL

tkanka biologiczna; proces zamrażania; zamrażanie tkanki

• Wydawca: Wydawnictwo Politechniki Częstochowskiej
• Czasopismo: Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
• Rocznik: 2011
• Tom: Vol. 10, nr 2
• Strony: 191--197
• Opis fizyczny: Bibliogr. 7 poz., rys.

Twórcy

autor

Mochnacki B.

autor

Siedlecki J.

• Czestochowa University of Technology, Poland,

Bibliografia

• [1] Majchrzak E., Mochnacki B., Sensitivity analysis and inverse problems in bio-heat transfer, Computer Assisted Mechanics and Engineering Sciences 2006, 13, 85-108.
• [2] Mochnacki B., Dziewoński M., Numerical analysis of cyclic freezing, Acta of Bioengineering and Biomechanics 2004, 6, 1, 476-479.
• [3] Mochnacki B., Suchy J.S., Numerical methods in computations of foundry processes, PFTA, Cracow 1995.
• [4] Majchrzak E., Modelowanie i analiza zjawisk termicznych, Biomechanika, ed. R. Będziński, IPPT PAN, 2011, 223-362.
• [5] Majchrzak E., Jasiński M., Janisz D., Identification of thermal parameters of biological tissue, Acta of Bioengineering and Biomechanics 2004, 6, 1, 467-470.
• [6] Kleiber M., Parametric Sensitivity in Nonlinear Mechanics, Theory and Finite Element Computations, J. Wiley and Sons 1997.
• [7] Majchrzak E., Mochnacki B., Numerical Methods. Theory, Practical Aspects, algorithms, Publ. of the Silesian University of Technology, Gliwice 2004 (in Polish).