Compressor Rotor Cooling via Inducer Flow Direction

Solution Overview

Problem

Higher overall pressure ratios in modern gas turbines result in increased compressor discharge temperatures, which challenge the creep and fatigue capability of the aft stages of compressors.

Innovation Solution

A compressor cooling apparatus that channels cooling air from a downstream diffuser to the final stage of the compressor, utilizing a stationary diffuser and an inducer to direct flow towards the blade row, thereby reducing peak temperatures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If higher overall pressure ratios are used in the gas turbine, then specific fuel consumption is improved, but compressor discharge temperature increases which challenges the creep and fatigue capability of the aft stages

Engineering Contradiction:

Improvespecific fuel consumptionVSAvoidcompressor discharge temperature

Core Design Contradiction:

Use of energy by moving objectVSTemperature

Solution Approach 1:

Cooling air is extracted from the diffuser downstream of the compressor and directed through the inducer to the final stage blade row in advance of the hot compressed air reaching it. This preliminary cooling action reduces the peak temperature of the air entering the combustor, allowing higher overall pressure ratios to be used without exceeding material temperature limits, thereby improving specific fuel consumption

Inventive Principle:

Principle #10Preliminary action

2Use of energy by moving object

If higher overall pressure ratios are used in the gas turbine, then specific fuel consumption is improved, but the creep and fatigue capability of the aft stages is challenged

Engineering Contradiction:

Improvespecific fuel consumptionVSAvoidcreep and fatigue capability

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

Cooling air is extracted from the diffuser downstream of the compressor and directed through the inducer to the final stage blade row in advance of the hot compressed air reaching it. This preliminary cooling action reduces the peak temperature of the air entering the combustor, allowing higher overall pressure ratios to be used without exceeding material temperature limits, thereby improving specific fuel consumption

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Significantly reduces transient peak temperatures, enabling the aft rim of the compressor to meet creep and cyclic life requirements while allowing for high overall pressure ratios that improve specific fuel consumption.

Implementation Method 1

an inducer disposed between the diffuser and the blade row, the inducer having an inlet in flow communication with the diffuser, and having an outlet oriented to direct flow towards the blade row

Methodology Applied

Scientific EffectFluid flow:

Data Source

PatentUS10746098B2Compressor rotor cooling apparatus

Publication Date: 2020.08.18 GENERAL ELECTRIC CO

AI summary

A compressor cooling apparatus includes: a blade row mounted for rotation about a centerline axis; a stationary diffuser located downstream of, and in flow communication with, the blade row; an inducer disposed between the diffuser and the blade row, the inducer having an inlet in flow communication with the diffuser, and having an outlet oriented to direct flow towards the blade row.