Background. To calculate actual indicators of thermal efficiency in respect to gas turbine units, scalar and vector formulations of the problem of regularization of material flows are used. They are based on the concept of Tikhonov's regularization when solving ill-posed problems. Analytical and numerical solutions of the problem have been obtained. It allows us to take into account the limitations on the range of permissible values of coolant flow rates, due to the metrological characteristics of the measuring instruments used. However, in the cases mentioned, the coolants enthalpy, depending on their thermophysical parameters, in particular pressure and temperature, are considered to be given. Taking into account the uncertainty of the results of measuring thermophysical parameters will make it possible to further increase the degree of validity of the results of simultaneous equations of the material and energy balances of gas turbine units.
Materials and methods. The problem of simultaneous equations of material and energy balances of a gas turbine unit taking into account the uncertainty of the results of measuring the thermal and physical parameters of coolants is set within the framework of Tikhonov's regularization concept. The statistical programming method is used for the numerical solution of the problem. The results have been tested using operational data on the GTX-100 gas turbine unit.
Results. The solutions to the problem of simultaneous equations of material and energy balances of a gas turbine unit have been obtained, taking into account the limitations on the range of permissible values of flow rates and heat engineering parameters of coolants and electric power, determined by the metrological characteristics of the measuring instruments. The authors have studied various options for setting and solving the problem and their influence on the results of calculating the thermal efficiency indicators of gas turbine units.
Conclusions. The proposed simultaneous equations method allows us to further increase the degree of reliability of the results of calculating the actual indicators of thermal efficiency of gas turbine units in comparison with the scalar and vector formulation of the problem at constant values of the thermal physical parameters of coolants. The method is applicable both to develop output performance standards of equipment, including processing the results of thermal balance tests, and to monitor operating units.