Advances in coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery

Abstract

Marine, industrial, turboprop and turboshaft gas turbine engines use nonaxisymmetric exhaust volutes for flow diffusion and pressure recovery. These processes result in a three-dimensional complex turbulent flow in the exhaust volute. The flows in the axial turbine and nonaxisymmetric exhaust volute are closely coupled and inherently unsteady, and they have a great influence on the turbine and exhaust aerodynamic characteristics. Therefore, it is very necessary to carry out research on coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics, so as to provide reference for the high-efficiency turbine-volute designs. This paper summarizes and analyzes the recent advances in the field of coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery. This review covers the following topics that are important for turbine and volute coupled designs: (1) flow and loss characteristics of nonaxisymmetric exhaust volutes, (2) flow interactions between axial turbine and nonaxisymmetric exhaust volute, (3) improvement of turbine and volute performance within spatial limitations and (4) research methods of coupled turbine and exhaust volute aerodynamics. The emphasis is placed on the turbine-volute interactions and performance improvement. We also present our own insights regarding the current research trends and the prospects for future developments.

Advances in aerodynamics of power turbines for marine and aviation applications

“…The recent research advances in coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery have been reviewed, and readers can refer to reference. 65…”

“…The recent research advances in coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery have been reviewed, and readers can refer to reference. 65 In addition, the variable geometry turbine is one of the effective means to importantly improve the performance of marine gas turbines and turboshaft/turboprop aeroengines under variable working conditions. In western developed countries, such as the United States and United Kingdom, in the aerodynamic design of the gas turbine power turbine, due to the adoption of variable geometry turbine technology, the matching relationship between the various components of the gas turbine has been effectively adjusted and optimized, thereby improving the acceleration and deceleration characteristics of the entire unit and the wide range of variable operating conditions performance.…”

Flow characteristics of last‐segment axial turbine adopted in compressed air energy storage system under low load and windage conditions

“…With the effects of complex flow under low load conditions, the maximum temperature occurred at the rotor blade tip and rotor blade operated in an over-temperature environment, 22,23 and the alternating stress and vibration were more likely to lead to the fatigue fracture of the turbine blade. 24,25 Therefore, the investigation of flow characteristics under low load and windage conditions can provide an aerodynamic theoretical basis for avoiding LAST blade damage.…”