ANALYSIS OF THE WAVE PROCESS IN THE COMPRESSED NATURAL GAS FLOW, WHICH OCCURS IN CASE OF A RAPID INCREASE IN GAS TURBINE LOAD
Alexander F. Maksimenko – Dr.Tech.Sci., professor, the Gubkin State University of Oil and Gas, maf@gubkin.ru maf@gubkin.ru

УДК 538.95, 544.272, 519.6
Key words: trunk gas pipeline, compressor unit, compressor station (CS), gas turbine unit (GTU), compressed natural gas, shock wave, expansion wave, thermodynamic parameters, sound velocity in natural gas, Mach number.
Seasonal variations in trunk gas pipeline throughput (typical of the Central Russia) affect the use of compressor station capacity. This, in particular, suggests that compressor stations should operate in a different mode. This is due to the changes in the operating parameters of individual compressors and compressor groups. The paper provides one-dimensional schematics of the gas dynamic process and analysis of shock wave and expansion wave propagation through the flow of compressed gas from gas compressors with a centrifugal injector of the gas turbine unit due to the increase shaft speed. It is shown that rapid increase in compressor load, increase in shaft speed and gas compression degree will cause the formation and downstream propagation of a shock wave and formation of an expansion wave in gas flowing into the gas compressor. The paper provides a solution to the problem of determining shock wave intensity and gas dynamics parameters of gas flow in front of and behind the expansion wave.

ANALYSIS OF THE WAVE PROCESS IN THE COMPRESSED NATURAL GAS FLOW, WHICH OCCURS IN CASE OF A RAPID INCREASE IN GAS TURBINE LOAD.
Alexander F. Maksimenko – Dr.Tech.Sci., professor, the Gubkin State University of Oil and Gas, maf@gubkin.ru

Key words: trunk gas pipeline, compressor unit, compressor station (CS), gas turbine unit (GTU), compressed natural gas, shock wave, expansion wave, thermodynamic parameters, sound velocity in natural gas, Mach number.
Seasonal variations in trunk gas pipeline throughput (typical of the Central Russia) affect the use of compressor station capacity. This, in particular, suggests that compressor stations should operate in a different mode. This is due to the changes in the operating parameters of individual compressors and compressor groups. The paper provides one-dimensional schematics of the gas dynamic process and analysis of shock wave and expansion wave propagation through the flow of compressed gas from gas compressors with a centrifugal injector of the gas turbine unit due to the increase shaft speed. It is shown that rapid increase in compressor load, increase in shaft speed and gas compression degree will cause the formation and downstream propagation of a shock wave and formation of an expansion wave in gas flowing into the gas compressor. The paper provides a solution to the problem of determining shock wave intensity and gas dynamics parameters of gas flow in front of and behind the expansion wave.