Centrifugal Separator Support for Axial Stability Under Negative Pressure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Centrifugal separators operating with negative pressure in the space surrounding the centrifuge bowl face challenges due to pressure differences affecting rotor dynamics, leading to potential axial displacement of the centrifuge bowl and compromising the operation of the separator.

Innovation Solution

A centrifugal separator design that includes a rotatable assembly suspended to permit radial movement relative to the casing, connected to a fixed structure via a nonelastic elongated element aligned with the rotational axis, ensuring the centrifuge bowl maintains its axial position despite negative pressure, thereby managing rotor dynamics without disrupting operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the rotatable assembly is suspended to permit radial movement relative to the casing, then rotor dynamics effects are accommodated, but the centrifuge bowl may experience axial displacement due to pressure difference

Engineering Contradiction:
Improveradial movement capabilityVSAvoidaxial position stability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The support structure is segmented into radial support elements that allow radial movement and axial constraint elements that prevent axial displacement. This segmentation enables independent handling of radial adaptability and axial stability requirements.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

An intermediary constraint mechanism is introduced between the rotatable assembly and casing that selectively permits radial movement while constraining axial displacement. This intermediary structure mediates between the conflicting requirements of radial flexibility and axial stability.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Temperature

If a pressure difference is maintained between the space and ambient environment, then heat generation from friction is reduced, but elements delimiting the space are subjected to resulting forces

Engineering Contradiction:
Improveheat generationVSAvoidforce on delimiting elements
Core Design Contradiction:
TemperatureVSForce

Solution Approach 1:

The support structure is designed to counterbalance the force resulting from the pressure difference. The axial constraint elements are positioned and dimensioned to provide counteracting support forces that neutralize the effect of pressure differential on the rotatable assembly.

Inventive Principle:
Principle #8Anti-weight (Counterweight)

Solution Approach 2:

The support structure is pre-designed to accommodate and cushion the forces that will result from the pressure difference during operation. The structure is prepared in advance to handle these forces without causing axial displacement.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Reliability

If seals are provided between stationary and rotating parts, then fluid containment is improved, but the complexity of the device increases

Engineering Contradiction:
Improvefluid containmentVSAvoidsealing arrangement complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The support structure serves multiple functions: it provides axial constraint, radial movement capability, and fluid containment through integrated sealing. This multi-functionality reduces the need for separate sealing components and simplifies the overall device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 maintains the axial position of the centrifuge bowl, ensuring reliable operation by balancing forces caused by pressure differences and rotor dynamics, allowing for efficient fluid separation without axial displacement.

Implementation Method 1

a pump arrangement connected to the space, wherein the pump arrangement is configured to remove gas from the space to provide a negative pressure within the space during operation of the centrifugal separator

Methodology Applied
Scientific EffectNegative pressure: Vacuum

Implementation Method 2

the centrifuge bowl forms a separation space which is sealed or isolated from the space, and in which separation space centrifugal separation of a higher density and a lower density component from a fluid takes place

Methodology Applied
Scientific EffectCentrifugal separation: Centrifugal Separation

Data Source

PatentEP4450165B1Centrifugal separator
Publication Date: 2025.10.15 ALFA LAVAL CORP AB
  • EP4450165B1 patent drawingFigure 1
  • EP4450165B1 patent drawingFigure 2
  • EP4450165B1 patent drawingFigure 3a~3b

AI summary

The disclosure concerns a centrifugal separator (2) comprising a rotatable assembly (4) configured to rotate about a rotational axis (6), a casing (8, 8') which delimits at least part of a space (10), and a pump arrangement (12) connected to the space (10). The space (10) is sealed, and the pump arrangement (12) is configured to remove gas from the space (10) to provide a negative pressure within the space (10). The rotatable assembly (4) comprises a centrifuge bowl (18) arranged within the space (10). The rotatable assembly (4) is connected to a fixed structure (28) via a securing structure (30) that is rigid in at least one direction along the rotational axis (6) such that the centrifuge bowl (18) is maintainable in an axial position along the rotational axis (6) when the space (10) is subjected to the negative pressure. The securing structure (30) comprises an elongated element (32).