Heavy Duty Gas Turbine Performance and Endurance Testing: The NovaLT™16 Experience

Abstract

The NovaLT™16 gas turbine recently developed in Baker Hughes, a GE company (BHGE), is part of a larger class of gas turbines (LT class) aiming at covering a wide space in the small power range segment and at introducing in the market a state of the art technology engine for what concerns performance, emissions, operability, durability and maintainability. The main purpose of this paper is to describe the entire validation campaign that was performed at BHGE facilities. This campaign can be divided into 3 different phases. The first phase focused on measuring engine performance in a new, clean and unaltered configuration. The second phase focused on emissions, vibration, thermal distribution, auxiliary system performances and the like, in order to validate the design assumption and calculation results across the full operational range. In this phase, more than 2000 sensors were installed across the entire engine, covering all modules, and all functional tests were performed (inside and outside of design space) to guarantee reliable engine behavior. At the end of this test phase, a full engine teardown was performed to allow a detailed parts inspection that confirmed the achievement of the design intent. The standard maintenance plan of the engine requires 35Kh continuous running. Therefore, the third part of the test aimed at validating engine durability with a full endurance test that allowed the identification and correction of any possible remaining operation problem. In this phase, the engine was still equipped with more than 1000 sensors, and was operated continuously following a well-defined operating profile in order to simulate both mechanical drive and power generation modes. This campaign successfully allowed to fine tune several engine control logic details, to monitor emissions behavior across a wide range of ambient temperature and load condition (the test spans from hot to cold day), to analyze trends of standard engine parameters and special instrumentation and, through planned borescope inspection, to evaluate individual component status versus selected operating profile. Data reported in this paper represent a summary of all the data acquired and post processing results, and illustrate how an endurance test can help tuning machine performance predictions in a wide operating range.

Advances in aerodynamic, structural design and test technology of variable geometry turbines

“…The variable geometry turbine is also used in industrial gas turbines and vehicle gas turbines to adapt to load changes and to improve multi-condition overall performance; the variable geometry technology has been also applied to the radial inflow turbines for turbochargers, etc. For GE NovaLT16 simple cycle industrial gas turbines, 6 the power turbine adopts variable geometry turbine technology to achieve wide-condition high efficiency, low emissions and fast response requirements of peak regulation. Using variable geometry turbines can also expand the freedom of selecting the working point of gas generator to ensure that the gas turbine has sufficient surge margin under all working conditions (Figure 4).…”