INSTRUMENTATION AND CONTROL OF EXPERIMENT
STAND
An experimental stand used for experimental part of the
research is based on commonly used small-scale boiler
intended for domestic heating. The boiler has nominal heat
output of 25 kW and the fuel are wooden pellets of diameter
6 ¬ 8 mm.
Fig. 1 depicts an overview of the boiler with extended
instrumentation and control. The fuel is fed from the pellet
hopper by the screw feeder onto the grate in the combustion
chamber. The fuel is combusted on the steel grate with
primary air flowing from inlet beneath the grate and
secondary air flowing through the holes in the side walls of
the combustion chamber. The primary/secondary ratio is
adjustable by a manual knob. The grate moves reciprocally
once every time period and thus shifting the burning pellet
towards the end of the grate to the ash bin where is collected
until manual disposal. Hot flue gas passes the heat exchanger
section to heat up water