Abstract
The purpose of this study is development of water tube boiler in tubular flame. The single water tube is inserted into the center of the tubular flame for using as a boiler. The flow field was measured by flow visualization in the water. The flow patterns were classified into three patterns; the forward flow, the stable reverse flow and the disturbed reverse flow. The axial velocity distribution with the water tube has the same distribution without the water tube. The combustion tests were carried out. The tubular flame was formed in the combustion chamber with the water tube, however, the flame became unstable due to the excess cooling by the water tube.
