Prof. Józef Telega, PhD, DSc


Habilitation thesis
1991Metody wariacyjne i analiza wypukła w zagadnieniach kontaktowych i homogenizacji 
Professor
1999Title of professor
Recent publications
1.Telega J., Kaczynski P., Smiałek M., Pawłowski P., Szwaba R., Suitableness of SLM Manufactured Turbine Blade for Aerodynamical Tests, Materials, ISSN: 1996-1944, DOI: 10.3390/ma16072866, Vol.16, No.7, pp.1-11, 2023
Abstract:

This paper describes some insights on applicability of a Selective Laser Melting and Direct Metal Laser Sintering technology-manufactured turbine blade models for aerodynamic tests in a wind tunnel. The principal idea behind this research was to assess the possibilities of using ‘raw’ DLMS printed turbine blade models for gas-flow experiments. The actual blade, manufactured using the DLMS technology, is assessed in terms of surface quality (roughness), geometrical shape and size (outline), quality of counterbores and quality of small diameter holes. The results are evaluated for the experimental aerodynamics standpoint. This field of application imposes requirements that have not yet been described in the literature. The experimental outcomes prove the surface quality does not suffice to conduct quantitative experiments. The holes that are necessary for pressure measurements in wind tunnel experiments cannot be reduced below 1 mm in diameter. The dimensional discrepancies are on the level beyond acceptable. Additionally, the problem of ‘reversed tolerance’, with the material building up and distorting the design, is visible in elements printed with the DLMS technology. The results indicate the necessity of post-machining of the printed elements prior their experimental usage, as their features in the ‘as fabricated’ state significantly disturb the flow conditions.

Keywords:

additive manufacturing,compressor blade,Direct Metal Laser Sintering (DLMS) technology,experimental aerodynamics,rapid prototyping,Selective Laser Melting SLM

Affiliations:
Telega J.-other affiliation
Kaczynski P.-other affiliation
Smiałek M.-other affiliation
Pawłowski P.-IPPT PAN
Szwaba R.-other affiliation
2.Gilewicz J., Pindor M., Telega J.J., Tokarzewski S., N-point Padé approximants and two sided estimates of errors on the real axis for Stieltjes functions, JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN: 0377-0427, DOI: 10.1016/j.cam.2003.12.051, Vol.178, pp.247-253, 2005
Abstract:

Upper and lower estimates of Stieltjes function by N-point Padé approximants can be obtained using the new general inequality reported by Tokarzewski et al. (Arch. Mech. 54 (2002) 141–153) and rigorously proved in the present paper. In addition, we prove that the multipoint Padé approximants to Stieltjes function are symmetric with respect to the order of choice of the considered points.

Keywords:

N-point Padé approximants, Stieltjes functions

Affiliations:
Gilewicz J.-other affiliation
Pindor M.-other affiliation
Telega J.J.-IPPT PAN
Tokarzewski S.-IPPT PAN
3.Gambin B., Gałka A., Telega J.J., Tokarzewski S., Influence of anisotropy induced by microcracks on effective elastic properties, ENGINEERING TRANSACTIONS (ROZPRAWY INŻYNIERSKIE), ISSN: 0867-888X, Vol.53, No.4, pp.409-420, 2005
4.Figurska M., Święszkowski W., Telega J.J., Influence of wear debris on behaviour and biomechanical properties of bone-implant interface, Russian Journal of Biomechanics, ISSN: 1812-5123, Vol.9, No.2, pp.20-32, 2005
Abstract:

The aim of this paper is to describe the effects of wear particles, generated during articulation of the bearing surfaces of the total joint prosthesis on bone-implant interface. Submicron particles migrate into effective joint space and stimulate cells present in the fibrous tissue to release molecular signal. Cytokines activate the osteoclasts and in consequence bone loss may result. It weakens the bone-implant fixation and may cause aseptic loosening of the prosthesis.

Keywords:

wear debris, bone–implant interface, total joint replacemtnt

Affiliations:
Figurska M.-IPPT PAN
Święszkowski W.-other affiliation
Telega J.J.-IPPT PAN
5.Piekarski J., Maździarz M., Glinkowski W., Telega J.J., Modeling of bone fracture healing, ACTA OF BIOENGINEERING AND BIOMECHANICS, ISSN: 1509-409X, Vol.6, No.Suppl.1, pp.191-194, 2004
6.Bielski W., Kruglenko E., Telega J.J., Young measures and their applications in micromechanics and optimization. I. Mathematical principles., Mathematica Applicanda (Matematyka Stosowana), ISSN: 1730-2668, DOI: 10.14708/ma.v31i45/04.1914, Vol.31, No.45/04, pp.90-138, 2003
Abstract:

The paper is a review of modern mathematical methods for the analysis of continuous problems of nonlinear mechanics and magnetism. The bibliography contains 175 items. The second part of the paper deals with mechanical problems described by nonconvex density energy functions and with numerical methods to solve such problems.

Affiliations:
Bielski W.-Institute of Geophysics (PL)
Kruglenko E.-IPPT PAN
Telega J.J.-IPPT PAN
7.Gilewicz J., Pindor M., Telega J.J., Tokarzewski S., Continued fractions, two-point Padé approximants and errors in the Stieltjes case, JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN: 0377-0427, DOI: 10.1016/S0377-0427(01)00538-6, Vol.145, No.1, pp.99-112, 2002
Abstract:

A Stieltjes function is expanded in mixed T- and S-continued fraction. The relations between approximants of this continued fraction and two-point Padé approximants are established. The method used by Gilewicz and Magnus (J. Comput. Appl. Math. 49 (1993) 79; Integral Transforms Special Functions 1 (1993) 9) has been adapted to obtain the exact relations between the errors of the contiguous two-point Padé approximants in the whole cut complex plane.

Keywords:

Two-point Padé approximation, Stieltjes functions

Affiliations:
Gilewicz J.-other affiliation
Pindor M.-other affiliation
Telega J.J.-IPPT PAN
Tokarzewski S.-IPPT PAN
8.Telega J.J., Wojnar R., Piezoelectric effects in biological tissues, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, Vol.40, No.3, pp.723-759, 2002
Abstract:

The aim of this paper is to analyze different contributions and differents points of view concerning the meaning of the piezoelectric effect in the bone. It is now obvious that this effect is overhelming in dry bone. In wet bone more important are streaming potentials.

Keywords:

bone, piezoelectricity

Affiliations:
Telega J.J.-IPPT PAN
Wojnar R.-IPPT PAN
9.Rojek J., Telega J.J., Stupkiewicz S., Contact problems with friction, adhesion and wear in orthopaedic biomechanics. Part II - Numerical implementation and application to implanted knee joints, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, Vol.39, No.3, pp.679-706, 2001
Abstract:

The present paper is the second part of the contribution by Rojek and Telega (2001). An alternative adhesion law was used to the study of bone-implant interface. Numerical scheme was developed and applied to the knee joint after arthroplasty. Influence of wear debris on this interface and currently used wear models were investigated.

Keywords:

unilateral contact, adhesion, friction, wear, knee joint after arthroplasty, FEM

Affiliations:
Rojek J.-IPPT PAN
Telega J.J.-IPPT PAN
Stupkiewicz S.-other affiliation
10.Jemioło S., Telega J.J., Representations of Tensor Functions and Applications in Continuum Mechanics, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.3, pp.1-112, 1997
11.Tokarzewski S., Telega J.J., S-Continued Fraction Method for the Investigation of a Complex Dielectric Constant of Two-Components Composite, Acta Applicandae Mathematicae, ISSN: 0167-8019, DOI: 10.1023/A:1005861519473, Vol.49, No.1, pp.55-83, 1997
Abstract:

The aim of this contribution is to examine the S-continued fraction method of obtaining bounds on the effective dielectric constant εe of a two-phase composite for the case where the dielectric coefficients ε1and ε2 of both components are either complex or real. The starting point for our study is a power expansion of εe(z) at(z)=0 (z)=ε2/ε1-1. The obtained S-continued fraction bounds have an interesting mathematical structure convenient for theoretical and numerical investigations of εe. They also agree with the earlier estimations reported by Bergman and Milton. Specific examples of calculation of bounds on εe by theS-continued fraction method are also provided.

Keywords:

composite medium, bounds, dielectric constants, Stieltjes function

Affiliations:
Tokarzewski S.-IPPT PAN
Telega J.J.-IPPT PAN
12.Bielski W., Telega J.J., A non-linear elastic plate model of moderate thickness: Existence, uniquenness and duality, JOURNAL OF ELASTICITY, ISSN: 0374-3535, DOI: 10.1007/BF00041792, Vol.42, No.3, pp.243-273, 1996
Abstract:

Three problems are solved for a nonlinear model of elastic plates with transverse shear deformations. The material of the plate may be anisotropic. An existence theorem is formulated and proved for a class of boundary conditions. A uniqueness theorem is given for small loadings. The dual problem is derived and the minimax or Lagrangian approach is discussed.

Affiliations:
Bielski W.-Institute of Geophysics (PL)
Telega J.J.-IPPT PAN
13.Telega J.J., Wojnar R., Main Polish Historical and Modern Sources on Applied Mechanics, Applied Mechanics Reviews, ISSN: 0003-6900, DOI: 10.1115/1.3101933, Vol.49, No.8, pp.401-432, 1996
Abstract:

The aim of thikocvzeń article is to present the list of books by Polish scientists on applied mechanics in a rather broad sense. An effort was made to cover the last century. Previous Polish sources, until 1874, were collected by Kucharzewski (1894). A list of the main journals in applied mechanics is also given, essentially covering the period starting after the Second World War.

Affiliations:
Telega J.J.-IPPT PAN
Wojnar R.-IPPT PAN
14.Gałka A., Telega J.J., Wojnar R., Some computational aspects of homogenization of thermopiezoelectric composites, Computer Assisted Mechanics and Engineering Sciences, ISSN: 1232-308X, Vol.3, No.2, pp.133-154, 1996
Abstract:

On the basis of the paper [1] two topics are discussed. Firstly, exact formulae for the homogenized coeffi-cients of a layered thermopiezoelectric composite are derived. Secondly, by applying the Ritz method, the local problems are solved approximately. Specific cases are also examined and illustrated.

Affiliations:
Gałka A.-other affiliation
Telega J.J.-IPPT PAN
Wojnar R.-IPPT PAN
15.Tokarzewski S., Telega J.J., S-continued Fraction Representation for Effective Transport Coefficients of Two-phase Media, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.16, pp.1-58, 1995
16.Telega J.J., Epi-limit on HB and homogenization of heterogeneous plastic plates, Nonlinear Analysis: Theory, Methods & Applications, ISSN: 0362-546X, DOI: 10.1016/0362-546X(93)E0017-W, Vol.25, No.5, pp.499-529, 1995
Keywords:

Epi-convergence in the strong topology of W11(Ω), space HB(Ω), homogenization of perfectly plastic plates, limit analysis and homogenization, periodically inhomogeneous material, relaxation of boundary conditions

Affiliations:
Telega J.J.-IPPT PAN
17.Bielski W., Telega J.J., Tarcie na uskokach geologicznych: modelowanie i wariacyjne sformułowanie zagadnień brzegowo-początkowych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.31, pp.1-30, 1994
18.Gałka A., Telega J.J., Wojnar R., Thermodiffusion in Heterogeneous Elastic Solids and Homogenization, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.14, pp.1-76, 1993
19.Gałka A., Telega J.J., Wojnar R., Homogenization and thermopiezoelectricity, Mechanics Research Communications, ISSN: 0093-6413, DOI: 10.1016/0093-6413(92)90050-K, Vol.19, No.4, pp.315-324, 1992
Abstract:

In [9] the formulae were derived for the effective moduli of a piezoelectric composite exhibiting fine periodic structure. The static case considered was studied by the method of F-convergence, cf.[l]. Next, in [10] these results were extended by investigating the dynamic behaviour. The same formulae for the effective moduli were obtained by using the method of Bloch expansions. The aim of this contribution is to present our preliminary results concerning homogenization of the equations of the linear thermopiezoelectricity. To such a problem the method of F-convergence is not applicable. Therefore the relevant analysis was performed by using the method of two-scale asymptotic developments. Our analysis leads to interesting conclusions related to the effective moduli and to the change of the initial condition for the temperature of the homogenized body.

Affiliations:
Gałka A.-other affiliation
Telega J.J.-IPPT PAN
Wojnar R.-IPPT PAN
20.Jemioło S., Telega J.J., Some Aspects of Invariant Theory in Plasticity, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.19, pp.1-31, 1992
21.Bielski W., Telega J.J., On Existence of Solutions and Duality for a Model of Non-linear Elastic Plates with Transverse Shear Deformations, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.35, pp.1-26, 1992
22.Telega J.J., Metody wariacyjne i analiza wypukła w zagadnieniach kontaktowych i homogenizacji (Praca habilitacyjna), Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.38, pp.1-209, 1990
23.Telega J.J., On Variational Formulations for Non-Linear, Non-Potential Operators, IMA Journal of Applied Mathematics, ISSN: 0272-4960, DOI: 10.1093/imamat/24.2.175, Vol.24, No.2, pp.175-195, 1979
Abstract:

This paper consists of two parts. In the first part the method for the choice of a bilinear form rendering a non-linear operator potential has been developed. The method constitutes an extension of Magri's approach, the last being valid for linear operators only.

The second part of the paper is concerned with the method of adding the adjoint operator. It has been proved that a system of two coupled operator equations consisting of a given non-linear operator equation and the equation determined by the adjoint of its Frechet derivative is described by a potential operator. The variational functional has been derived. Some particular cases have been discussed.

Affiliations:
Telega J.J.-IPPT PAN
24.Telega J.J., On Plane Plastic Flow of Compressible Solids, ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK, ISSN: 0044-2267, DOI: 10.1002/zamm.19780580303, Vol.58, No.3, pp.133-142, 1978
Abstract:

Equations of plane compressible flow of perfectly-plastic solids are derived from a three-dimensional, tensorially nonlinear theory of Sawczuk and Stutz. In plane flow the flow rule reduces to a linear relation. The flow law is, in general, not associated with the yield condition. The system of stress and velocity equations may be hyperbolic, parabolic or elliptic depending upon the material constants and dilatancy. The second order effects manifest in the expressions describing the stress and velocity fields, the yield condition and the power of dissipation.

Affiliations:
Telega J.J.-IPPT PAN
25.Sawczuk A., Telega J.J., A remark on plane plastic motion, Mechanics Research Communications, ISSN: 0093-6413, DOI: 10.1016/0093-6413(75)90010-5, Vol.2, No.4, pp.209-214, 1975
26.Telega J.J., Metoda elementów skończonych w mechanice ciał odkształcalnych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.55, pp.1-107, 1975
27.Telega J.J., O warunkach plastyczności i równaniach konstytutywnych dla izotropowego ośrodka sztywno-plastycznego, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.22, pp.1-23, 1974
28.Telega J.J., Metoda elementów skończonych w mechanice ciał odkształcalnych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.46, pp.1-87, 1973

List of recent monographs
1.
30
Shillor M., Sofonea M., Telega J.J., Models and Analysis of Quasistatic Contact, Variational Methods, Springer-Verlag Berlin Heidelberg, Series: Lecture Notes in Physics, 655, pp.1-239, 2004
List of chapters in recent monographs
1.
174
Telega J.J., Stańczyk M., Modelling in biomechanics (OBM'02), AMAS Lecture Notes 19, rozdział: Modelling of soft tissues beahaviour, IPPT PAN, AMAS, ABIOMED (Warszawa), Telega J.J. (Ed.), 19, pp.191-454, 2005
2.
209
Telega J.J., Stańczyk M., Tissue remodelling, ABIOMED Lecture Notes 3, rozdział: Residual stresses and strains and remodelling of tissues, IPPT PAN, ABIOMED (Warszawa), Piekarski J. (Ed.), 3, pp.319-391, 2005