Volume 3: Innovative Solutions for Energy Transitions: Part II

Experimental Validation of An Algorithm for Determining Transient Stresses within Pressure Components by Means of the Tensometric Method Marcin Pilarczyk, Bohdan Węglowski, Lars O. Nord

Abstract

The article presents an experimental validation of an algorithm for determining transient stresses within pressure components which are extensively employed in industry. The algorithm is based on the solution of the Inverse Heat Conduction Problem (IHCP) and incorporates temperature measurements on the outer surface of the analysed components. For validation purposes, a laboratory stand was modernised and 19 new dedicated strain gauges (SG) were installed. The novelty of this work is the validation of calculated transient stresses on the component’s outer surface by means of tensometric methods. A crucial aspect is the appropriate correction of the measured values of strains because the measure properties of SGs vary with temperature. The scope of the article covers an analysis of the stresses on the cylinder’s inner surface as well. The calculated and measured values were compared to values obtained from a generalized theory of quasi-state heating, which incorporates a thermocouple located in the component wall. The agreement between all methods was satisfactory. This broadly validated inhouse algorithm is suitable for comprehensive monitoring of working conditions of critical components in various industrial installations.

Keywords power unit, thermal stress, thick-walled header, strain gauge, transient state, temperature field