TÍTULO: Modelling of Bioheat Problems within Newborn Brain Cooling Processes
PALESTRANTE: Andrzej J. Nowak
Institute of Thermal Technology, Silesian University of Technology, Poland
LOCAL: Centro de Tecnologia, Bloco G, Sala 219
DATA: 12/07/2013
HORÁRIO: 13:30h
ABSTRACT:
The perinatal hypoxic-ischemic encephalopathy is a fairly frequent problem which the neonatologists have to cope with. In order to perform the treatment in a proper way a distribution of the temperature inside the neonatal body (especially inside the brain) during the whole therapy should be known. It has been already proved that temperature level of 34-34.5oC is secure during brain cooling, and at the beginning of the therapy the deep body temperature is decreased to that level. In the case of neonate suffering from the hypoxia his temperature is usually decreasing spontaneously and at certain moment neonatologists can start therapy. If not, his temperature has to be reduced utilising cooling helmet or other device. Next, during the therapy, the deep body temperature is maintained at the constant level. Since the most vulnerable organ is the brain, the temperature of the scalp is kept by cooling helmet at the lowered level equal to about 24oC. Simultaneously, in order to maintain the deep body temperature at the secure level, the skin of the rest of the neonatal body has to be heated by the radiant warmer. The therapy is carried out for 72 hours and then the deep body temperature is gradually increased to the normal level (about 37oC). It is very important to guarantee that temperature augments not faster than 0.5 K per hour, what entails many enormous difficulties.
In this work the attempt was made to simulate numerically the heat transfer in the neonatal body during the brain cooling process. The main aim of the analysis was to find the proper parameters of the process. At the beginning the simplified geometric model of the newborn’s body was built by use of the Design Modeler. As the shape of the head an ellipsoid was used. The forms of neck and trunk were simplified to elliptic cylinders. The limbs were modelled as cylinders. Inside the head the scalp, scull and brain were separated. The brain was surrounded by the brain cerebrospinal fluid. The remaining part of the head was modelled as a space occupied by the air. The neck consisted of the spine, muscle and skin. The spine was lengthened to the torso. Interior of the trunk was divided into lungs and viscera, which were surrounded by bone and skin. Limbs were split into three tissues: bone, muscle and skin. Position of the legs was similar to the arrangement of the sleeping neonate’s legs. The heating mattress, the cooling helmet and the surrounding air were also considered in the model.
Subsequently, by use of Ansys Fluent and its UDF (User Defined Function) capability, the mathematical model of the bioheat transfer in the neonatal body was created. This model utilises the Pennes bioheat equation and its coupling to the blood circulation model. All thermal and flow parameters occurring within developed model are determined through the inverse analysis. The results of the numerical computations were also compared with the data obtained from neonatologists. Despite adopted simplifications the performed analysis resulted in the proper parameters of the cooling process of the neonatal brain.
BIOGRAPHICAL INFORMATION:
Prof. Andrzej J. Nowak
Vice Director of the Institute of Thermal Technology (Education)
room C-210
Konarskiego 22
44-100 Gliwice
tel.: +48 32 237 10 25
fax: +48 32 237 28 72
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
personal website: www.itc.polsl.pl/nowak
Degrees
•Professor (Polish - profesor tytularny), 2005
•DSc (Polish - dr habilitowany), Silesian University of Technology, Faculty of Power and Mechanical Engineering, 1993
•PhD (Polish - dr nauk technicznych), Silesian University of Technology, Faculty of Power and Mechanical Engineering, 1978
•MEng chemical engineering (Polish - mgr inż. konstrukcja aparatury chemicznej), Silesian University of Technology, Faculty of Chemical Technology and Engineering, 1974
Employment record
•Full Professor (Polish - profesor zwyczajny), Silesian University of Technology, since October 2007
•Vice Chair for Education - (Polish - Z-ca Dyrektora d/s Dydaktyki), Silesian University of Technology, since September 2006
•Professor (Polish - profesor nadzwyczajny z tytułem naukowym), Silesian University of Technology, since May 2005
•Professor (Polish - profesor nadzwyczajny), Silesian University of Technology, since May 1, 2003 till April 4, 2005
•Associate Professor (Polish - adiunkt ze stopniem dr hab.), Silesian University of Technology, February 15, 2003 - May 1, 2003
•Professor (Polish - profesor nadzwyczajny), Silesian University of Technology, since 1995 till February 15, 2003
•Professor (Polish - profesor nadzwyczajny), Silesian School of Economics and Languages, Katowice, 2001-2004, part-time
•Visiting professor, Wessex Institute of Technology, UK, 15 months between 1986-1992
•Visiting research fellow, Wessex Institute of Technology, UK, 3 month in 1991
•Associate Professor (Polish - adiunkt ze stopniem dr hab.), Silesian University of Technology, 1993-1995
•Assistant Professor (Polish - adiunkt), Silesian University of Technology, 1978-1993
•Assistant Professor (Polish - adiunkt) Łódź University of Technology, 1978-1981, part-time
•PhD student, Institute of Thermal Technology, Silesian University of Technology, 1975-1978
•Trainee, Institute of Thermal Technology, Silesian University of Technology, 1974-1975
•Trainee, Design Office of Fire Resistant Materials PIPROMOG, Gliwice, 1974
Member of journal and book series Scientific Editorial Boards
•Engineering Analysis with Boundary Elements
•International Journal of Numerical Methods for Heat and Fluid Flows
•International Editorial Board of International Series on Computational Engineering
Reviewer for scientific journals
•Mathematical Problems in Engineering
•Computer Methods in Applied Mechanics and Engineering
•The Journal of Applied Physiology
•Engineering Analysis with Boundary Elements
•International Journal of Heat and Mass Transfer
•International Journal for Numerical Methods in Engineering
•International Journal Numerical Methods for Heat and Fluid Flows
•Numerical Heat Transfer
•Journal of The Royal Society, Interface
•Electronic Journal for Boundary Elements
•Energy - The International Journal
•Journal of Mechanical Engineering
•Transaction of IFFM
•Institute of Physics - Inverse Problems
•Institute of Physics - Applied Physics
•Archives of Thermodynamics
Reviewer of PhD theses, DSc dissertations and reviewer in promotion to the professor position
•reviewer of 17 PhD theses (Dr Nehad A. Hussen Al-Khalidy - Silesian University of Technology, Dr Damian Słota - Silesian University of Technology, Dr Leszek Pająk - AGH University of Science and Technology, Dr Leszek Hożejowski - Kielce University of Technology, Dr Aleksander Nawrat - Silesian University of Technology, Dr Marek Bartoszek - Silesian University of Technology, Dr Małgorzata Król - Silesian University of Technology, Dr Jacek Jamborski - Silesian University of Technology, Dr Krzysztof Sikora - University of Bielsko-Biała, Dr Piotr Krawczyk - Warsaw University of Technology, Dr Mirosław Seredyński - Warsaw University of Technology, Dr Maciej Woś - West Pomeranian University of Technology, Dr Arkadiusz Ryfa - Silesian University of Technology, Dr Witold Wróbel - AGH University of Science and Technology, Dr Agnieszka Cebo-Rudnicka - AGH University of Science and Technology, Dr Piotr Warzecha - Częstochowa University of Technology, Dr Łukasz Pyrda - AGH University of Science and Technology)
•reviews of 4 DSc dissertations (Dr hab. Irena Wilkosz - Silesian University of Technology, Dr hab. Ryszard Korycki - Technical University of Łódź, Dr hab. Dorota Bzowska - Institute of Fundamental Technological Problems in Warsaw, Dr hab. Marcin Janicki - Technical University of Łódź)
•reviewer in 4 promotions to professor (Dr. Ted A. Conway - promotion to the rank of Professor, University of Central Florida, USA, Dr. Daniel Lesnic - application for a Readership in Applied Mathematics, Leeds University, UK, Prof. Krzesztof Grysa - promotion to the rank of Full-time Professor, Kielce University of Technology, Poland, Prof. Norbert Sczygiol - promotion to the rank of Full-time Professor, Częstochowa University of Technology)