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Calculation and experimental investigations were carried out to determine the parameters of the impulse air jet created by the pneumatic generator of the air-impact system of the cleaning of tubular heat exchangers in boilers. Two configurations (lengthwise and checkerboard) of the arrangement of tubular heat exchangers located at distances from 1.0 m to 2.5 m of nozzle exit were experimentally investigated and the forces acting on them were determined. Numerical modeling of the impulse jet impact on heat exchange tubes was carried out. It was shown that an increase in the pressure of the generated impulse jet to 2.35 MPa makes it possible to significantly increase the acting force from 78 N to 1881 N at a large distance from the exhaust nozzle. The results obtained can be used in the development of specific systems for air impact cleaning systems of boiler units with other sizes and configurations of the heat exchange tubes.

The slagging of heating surfaces by fly ash significantly complicates the long term operation of solid-fuel boilers. Gas pulse technologies offer a potentially convenient, inexpensive, yet efficient way for online slag deposits removal. The creation and application of real boiler cleaning systems using gas pulse technologies is a relatively new direction in the energy sector and requires scientific research on various aspects. In this work, the numerical investigation of the gas-dynamic flow arising when the package of heat-exchange tubes is blown with single air jet created by a pneumopulse cleaning system has been carried out. The forces acting on the heat-exchange tubes located at distances 1.0 m and 2.0 m from the exhaust nozzle with various configurations of tubes in the package have been determined. It is shown that an increase in the pressure of the generated air jet makes it possible to significantly increase the acting forces at large distances from the exhaust nozzle. The results of this study and similar calculations for real geometry will increase the validity of engineering solutions used in the development of pneumopulse cleaning systems for large power boilers.