Centrifugal Compressor Throttle Strut Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing centrifugal compressor systems face challenges in improving efficiency at low flow rate operating points due to backflow issues and lack of a simplified configuration for transmitting driving force to throttle mechanisms.
Innovation Solution
A centrifugal compressor design featuring a throttle mechanism with an annular portion and a strut that moves between positions to reduce the intake passage area, incorporating inclined surfaces and a reduced strut length to minimize pressure loss and system complexity, while using available spaces for actuators to prevent enlargement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the flow passage area of the intake passage is reduced by the throttle mechanism, then the efficiency at low flow rate operating point is improved, but the peak efficiency is reduced due to the reduced area
Solution Approach 1:
The patent applies a variable throttle mechanism that dynamically adjusts the flow passage area of the intake passage based on operating conditions. The throttle mechanism moves between a first position (reducing flow area) and a second position (increasing flow area), allowing the system to optimize efficiency at low flow rate operating points while maintaining peak efficiency at high flow rates. This dynamic adjustment resolves the contradiction by making the flow passage area adaptive rather than fixed.
2Ease of operation
If the strut extends upstream in the axial direction from the annular portion, then the driving force can be transmitted to move the annular portion, but the length of the strut increases and the configuration becomes complex
Solution Approach 1:
The patent changes the orientation of the strut from extending in the axial direction to extending in the radial direction from the annular portion. This dimensional change allows the driving force to be transmitted effectively while significantly reducing the strut length and simplifying the overall configuration. The radial extension enables the actuator to be positioned more compactly within the compressor structure.
3Ease of operation
If the strut length is increased to transmit driving force, then the annular portion can be moved between positions, but the pressure loss in the intake passage increases
Solution Approach 1:
The patent reduces pressure loss by reorienting the strut to extend radially rather than axially. This dimensional change shortens the strut length, minimizing its intrusion into the intake passage flow path and thereby reducing pressure loss while still enabling effective transmission of driving force to move the annular portion between positions.
4Extent of automation
If the actuator is installed in the centrifugal compressor to move the annular portion, then the throttle mechanism can be operated, but the centrifugal compressor size increases
Solution Approach 1:
The patent positions the actuator within the space between the inclined surface of the inlet pipe portion and the diffuser portion, effectively nesting the actuator within existing structural voids of the compressor. This nesting approach allows the throttle mechanism to be automated without significantly increasing the overall compressor size, as the actuator utilizes otherwise unused space within the compressor housing.
Data Source
AI summary
A centrifugal compressor includes: an impeller; an inlet pipe portion forming an intake passage to introduce air to the impeller; and a throttle mechanism capable of reducing a flow passage area of the intake passage upstream of the impeller. The throttle mechanism includes an annular portion configured to move between a first position and a second position upstream of the first position in an axial direction of the impeller, and a strut supporting the annular portion. The strut extends toward at least one of an outer side in a radial direction of the impeller or a downstream side in the axial direction of the impeller with an increase in distance from the annular portion.