Kanygin A. Raising the level of gas-fired firetube hot–water boilers effectiveness.

This study deals with enhancing of control techniques in gas-fired hot–water boilers. The grounded configuration of new watertube–firetube boiler based on radial watertube bank installation in the room of a cylindrical fire tube had been worked out and has been approved. Efficiency of a 630 KWt watertube–firetube boiler is determined by numerical computer simulation and experiment. The findings allowes to carry out the comparative analysis on efficiency of the watertube–firetube boiler with the firetube boilers of standart design at diffusive burning of natural gas. Thermophysical performance of the fire tubes had been examined and the suggestions in relation to correction of Nondimensional Temperature method in calculation of firetube boilers furnaces and watertube–firetube boiler furnace have been presented. The method of estimation of thermal mechanical stresses occurring in heating surfaces of shell boilers had been developed, on the basis the reliability of watertube–firetube boiler furnace has been considered. Results of the study are applied in industry at working out, erection and operation of the production prototype of KVVD-0.63 Gn (630 KWt watertube–firetube gas-fired boiler).