Probes for measuring heat transfer parameters and fouling intensity in boilers

Some constructions of probes used in Tallinn Technical University for investigation of fouling intensity and heat transfer in solid fuel boilers are presented. The strong separation must be done between the operation conditions of probes for measuring the incident and resultant heat fluxes. For measuring resultant fluxes the idea of heat conductivity in thick metal wall mainly is used. Some results of measuring the thermal efficiency dynamic in boilers for Siberian brown coal, Donetsk coal and black liquor are presented. These results are compared with the data on laboratory investigation of the emissivity of ash deposits.