A Non-Dimensional Consideration in Combustor Axial Stress Computations

Ebene Ufot, Barinaadaa Thaddeus Lebele-Alawa, Ibiba Emmanuel Douglas, Kelvin D. H. Bob-Manuel

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DOI: 10.4236/eng.2010.29095                

Abstract

Thermal stresses in the combustor of gas-turbines are computed using non-dimensional parameters. Buckingham pi theorem was used to arrange the listed relevant parameters into non-dimensional groups. In testing the validity of the functional relation of the non-dimensional independent parameters, use is made of the prevailing temperatures of the combustor in operation. A computer program was used to enhance computations. The results showed an interesting way of influencing the axial stresses. To reduce stresses in gas-turbine combustors, a method of varying the independent parameter that is of radius ratio oriented and thickness dependent was adopted. This showed a reduction of the axial stresses to minimal levels using the parameters. Plots were made and a point of inflection that manifested itself in the presentation of the axial stress function was further investigated upon. It turned out to be a point of abnormal stress level and out-of-trend temperature profile. The use of non-dimensional consideration proved adequate in the computation of axial stresses. The results showed a 2 percent difference from existing values of stresses got from a transient thermal loading of a combustor.

Keywords

Thermal, Stresses, Combustor, Gas-Turbine

Conflicts of Interest

The authors declare no conflicts of interest.

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