The investigation of the impact of basic operational parameters on the dynamics of water jacket in a biomass boiler using numerical and experimental methods

AGH University of Science and Technology, Faculty of Energy and Fuels, 30 Mickiewicza Av. 30-059 Krakow, Poland

^a Corresponding author: mszubel@agh.edu.pl

Published online: 6 May 2015

Abstract

Biomass boiler application, despite its many advantages, is dependent upon many technical aspects, which require tests and optimization. Because of practical constraints, one of the most problematic areas of research is the analysis of phenomena occurring inside the water jacket of the boiler during the combustion process. The issue referred to above is significant due to its direct impact on the heating up of the operating medium for current power of the device and the total efficiency. The paper presents the analytical possibilities of the operating medium in a biomass boiler water jacket. The experimental works conducted as a part of the study were performed using an actual device – EKOPAL RM 40 straw boiler. They were aimed at defining the values of significant boundary conditions. Resistance thermometers and K-type thermocouples connected to a data acquisition system were placed in selected points of the water jacket and the combustion chambers to allow the monitoring of the conditions of the water heating process during biomass combustion. A measurement of inlet water mass flow rate was performed. To develop a numerical model of heat transfer into the water jacket, ANSYS CFX software was applied. The results of the experiments and simulations were compared and discussed. The paper describes the methodology and instruments used to perform the experimental studies, as well as some optimization solutions developed based on the results of the numeric alanalysis.