Centrifugal Compressor Inlet Member Geometry for Surge Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Centrifugal compressors experience a decrease in efficiency due to insufficient blocking of strong backflow of air by the movable member, leading to surging.
Innovation Solution
The centrifugal compressor design includes a movable member with a specific curvature radius and fillet portion, extending portion, and radial distance configuration to effectively block backflow and maintain efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the movable member protrudes into the intake flow path to block backflow, then surging is suppressed, but strong backflow of air may not be sufficiently blocked and efficiency decreases
Solution Approach 1:
The movable member features a curved inner surface with a specific curvature radius relationship (second end curvature radius > first end curvature radius). This curvature design optimizes the flow characteristics of air passing through the movable member, reducing flow separation and turbulence while maintaining effective backflow blocking capability, thereby preventing efficiency loss even when blocking strong backflow
Solution Approach 2:
The patent specifies precise geometric parameters including curvature radii ratios and radial distances (e.g., radial distance between inner circumferential edge and extending portion is 20-80% of thickness). By optimizing these parameters, the movable member achieves optimal balance between backflow blocking effectiveness and flow resistance, maintaining compressor efficiency while suppressing surge
2Reliability
If the movable member blocks the intake flow path to prevent backflow, then surging is suppressed, but pressure loss increases
Solution Approach 1:
The curved inner surface design with increasing curvature radius from first end to second end creates a gradual flow transition zone. This reduces flow separation and turbulence when air passes through the movable member, minimizing pressure loss while maintaining backflow blocking capability
Solution Approach 2:
The movable member has different geometric characteristics at different locations: the first end region (facing compressor impeller) has smaller curvature radius for effective backflow blocking, while the second end region (facing intake port) has larger curvature radius for smooth flow transition. This local differentiation optimizes both surge suppression and pressure loss reduction
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
The design effectively suppresses backflow and maintains efficiency by blocking air backflow, expanding the operating region and reducing pressure loss.
Implementation Method 1
a compressor impeller disposed in the intake flow path
Implementation Method 2
The movable member is movable to a protruding position protruding into the intake flow path and a retracted position retracting from the intake flow path. When the movable member protrudes into the intake flow path, the air flowing backward in the intake flow path is blocked by the movable member.
Data Source
AI summary
A centrifugal compressor includes: an intake flow path connected to an intake port; a compressor impeller disposed in the intake flow path; a movable member provided on the intake port side with respect to the compressor impeller in the intake flow path, the movable member movable to a protruding position protruding into the intake flow path and a retracted position retracting from the intake flow path; a first end that is an end, on the compressor impeller side, of an inner curved surface of the movable member; a second end that is an end, on the intake port side, of the inner curved surface of the movable member; and an extending portion between the first end and the second end, the extending portion extending in a direction corresponding to a rotation axis direction of the compressor impeller.