BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI
Publicat de
Universitatea Tehnică „Gheorghe Asachi” din Iaşi
Tomul LVI (LX), Fasc. 2, 2010
Secţia
CONSTRUCŢII DE MAŞINI
CONTRIBUTIONS REGARDING DURABILITY EVALUATION
OF HORIZONTAL AXIAL HYDRAULIC TURBINES SHAFTS
BY
ILARE BORDEASU 1 , MIRCEA OCTAVIAN POPOVICIU 1 , DRAGOS
NOVAC 2 , LIVIU MARSAVINA 1 , RADU NEGRU 1 , MIRCEA VODA 1 ,
VICTOR BALASOIU 1 and MARIAN BĂRAN 1
Abstract. Using previous researches regarding cracks initiation, the present
paper analyzes the durability of horizontal bulb turbines shaft, especially in the
joining zone between the shaft main body and the runner flange. For
exemplifying, there were used the data of the turbines running in the Power Plants
Iron Gates II and Gogosu. The obtained conclusions can be used to avoid serious
failures of horizontal hydraulic turbines. The abstract of the paper is to be written
here. It contains the main ideas and original contributions and conclusions of the
authors’ research.
Key words: axial hydraulic turbines, cracks, stress alternation cycles, fracture
mechanics characteristics
1. Introduction
It is a well-known fact that during of the turbine running (rotational
motion), under the effect of: hydraulic forces and moments developed on the
blades, runner masses (with or without oil) and vibration, the turbine shaft is
submitted to specific variable stresses (tension, bending and torsion). Taking
into account the results obtained in [1], in the present work, the durability of the
horizontal axial hydraulic turbines shaft was evaluated using the professional
programs ANSYS and AFGROW. In order to obtain also numerical examples
were used the bulb turbines in function at the Power Plants Iron Gates II and
Gogosu, for which we know the necessary data. The obtained conclusions allow
avoiding dangerous troubles during the turbine operation.