NUMERICAL METHOD FOR DETERMINING ALLOWABLE MEDIUM TEMPERATURE DURING OPERATION OF STEAM GATE VALVE

Authors

  • Piotr Duda Cracov University of Technology
  • Dawid Rząsa Cracov University of Technology

Keywords:

thermal stresses, steam boilers, heat transfer, optimization

Abstract

Construction elements of power blocks such as collectors, separators or steam valves work in hazardous environment. During start-up and shut-down operations they are exposed to sudden temperature and pressure changes, that cause high stresses at certain points. Additionally, the cyclic character of loading causes material fatigue, known as low-cyclic fatigue, which may lead to the formation of fracture. Manufacturers of steam boilers provide instructions for heating and cooling processes in order to operate safely. It is important to find the optimum parameters for heating and cooling operations, i.e. parameters that enable to conduct heating and cooling in the shortest time and keep the maximum stresses in the construction within allowable limits. Efforts are made to develop an appropriate method for determining optimum operating parameters during start-up and shut-down phase of the power units. In this paper two optimum parameters will be found. Based on these parameters heating and cooling processes will be carried out and compared with heating and cooling operations processed according to the German boiler regulations Technische Regeln für Dampfkessel 301 (TRD).

Downloads

Download data is not yet available.

References

Duda P., Dwornicka R. 2008, Optimization of heating and cooling operations of steam gate valve. Proc. International Conference on Engineering Optimization EngOpt 2008, Rio de Janeiro, Brazil, June 2008, Jose Herskovits - Editor, p. 52 (on CD 8 pages).

Duda P., Taler J. 2009, A new methodfor identification of thermal boundary conditions in water-wall tubes of boiler furnaces. International Journal of Heat and Mass Transfer, vol. 52, pp. 1517-1524.

Press W.H., Teukolsky S.A., Vetterling W.T., Flannery B.P. 2007, Numerical Recipes: The Art of Scientific Computing, 3rd ed., Cambridge University Press, Cambridge, ISBN-10: 0521880688.

Richter F. 1983, Physikalische Eigenschaften von Stählen und ihre Temperaturabhängigkeit. Mannesmann Forschungberichte 930, Düsseldorf.

Rusin A., Banaszkiewicz M., Lipka M., Lukowicz H., Radulski W. 2005, Continuous control and optimization of thermal stresses in the process of turbine start-up. Congress of Thermal Stresses, Wienna, Austria, May 2005, pp. 425-428.

Seber G.A.F., Wild C.J. 1989, Nonlinear Regression. John Wiley&Sons, New York, ISBN-10: 0471617601.

Taler J., Duda P. 2006, Solving direct and inverse heat conduction problems, Springer-Verlag, Berlin-Heidelberg, ISBN-10: 354033470X.

Taler J., Dzierwa P. 2007, A new method for determining allowable medium temperature during heating and cooling of thick-walled boiler components. Proc. 7th International Congress on Thermal Stresses, Taipei, Taiwan, June 2007, vol. 2, pp. 437-440.

Taler D., Taler J. 2009, Optimum heating of thick plate. International Journal of Heat and Mass Transfer, vol. 52, pp. 2335-2342.

TRD 301 (1986) Technische Regeln für Dampfkessel, Carl Heymans Verlag, Köln und Beuth-Verlag, Berlin, ISBN-10: 3452254216, pp. 98-138

Downloads

Published

2010-10-17

Issue

Section

Articles