Photodetector Array Interface Detection in Centrifugal Separators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fluid processing systems, particularly in centrifuges, rely on time-based optical signal measurements for detecting and controlling the interface between separated fluid components, which can be inefficient due to dependencies on photodetector surface area, laser spot size, and signal amplification, leading to suboptimal collection of separated components.
Innovation Solution
An interface monitoring assembly is introduced, comprising a light source, a photodetector array, and a collimator, which emits and receives collimated light through the centrifugal separation chamber, allowing for precise detection of the interface between fluid components and enabling the controller to adjust the separation process for optimal component collection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If time-based optical signal measurements are used for interface detection, then the system can detect the interface between separated fluid components, but the measurement resolution is limited by photodetector surface area and laser spot size
Solution Approach 1:
The photodetector is divided into multiple discrete segments or elements arranged in an array, where each segment corresponds to a specific spatial position. This segmentation allows the system to detect interface position across multiple locations simultaneously, improving measurement resolution without requiring complex signal amplification for a single large photodetector.
Solution Approach 2:
The invention transitions from time-based optical signal measurements to spatial-based measurements by using an array of photodetectors positioned at different locations. This dimensional change from temporal to spatial domain allows direct determination of interface position based on which photodetector elements are activated, eliminating the need for complex time-based signal analysis and amplification circuitry.
2Use of energy by moving object
If larger photodetector surface area is used to improve signal detection, then more light can be detected, but the measurement resolution decreases
Solution Approach 1:
The photodetector surface is segmented into multiple smaller detection elements arranged in an array. Each element captures light independently, and the collective activation pattern of these elements provides both sufficient total light detection capability and high spatial resolution for precise interface position determination.
Solution Approach 2:
Instead of increasing the surface area of a single photodetector, the invention uses multiple smaller photodetectors arranged spatially. This transforms the problem from one requiring large surface area to one solved by spatial distribution, maintaining high light detection capability while achieving superior measurement resolution.
3Reliability
If signal amplification is increased to improve detection sensitivity, then weak optical signals can be detected, but the circuitry time constants increase affecting rise and fall time
Solution Approach 1:
The use of multiple segmented photodetector elements allows the system to detect interface position by identifying which segments are activated, rather than relying on amplifying weak signals from a single photodetector. This approach maintains high detection sensitivity while using simpler, faster electronic circuits with shorter time constants.
Solution Approach 2:
The invention shifts from temporal signal analysis requiring amplification to spatial pattern recognition. By determining interface position based on which photodetector elements are activated rather than analyzing signal amplitude over time, the system achieves high sensitivity without the speed penalties associated with signal amplification circuitry.
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
This solution enhances the accuracy and efficiency of interface detection, allowing for real-time adjustments to maintain the interface at a target location, thereby improving the quality and efficiency of fluid separation and collection.
Implementation Method 1
a collimator positioned between the light source and the light detector, wherein the collimator is configured to receive at least a portion of the light emitted by the light source and direct collimated light through a channel defined by a centrifugal separation chamber
Implementation Method 2
a light detector configured as a photodetector array... the light detector is configured to receive at least a portion of the collimated light exiting the channel of the centrifugal separation chamber... and the light detector is configured to emit a signal indicative of a location of an interface between separated fluid components
Implementation Method 3
a centrifugal separator configured to rotate a centrifugal separation chamber about a rotational axis... rotating the centrifugal separation chamber about a rotational axis so as separate at least a portion of the fluid in the channel of the centrifugal separation chamber
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Systems and methods are provided for determining and controlling the location of an interface between separated fluid components within a channel of a centrifugal separation chamber being rotated about a rotational axis. Light from a light source is received by a collimator, which directs collimated light through the channel in a direction substantially parallel to the rotational axis. At least a portion of the collimated light exiting the channel is received by a light detector configured as a photodetector array. A signal emitted by the light detector is received by a controller, which determines the location of an interface between separated fluid components within the channel based at least in part on the signal. When the controller determines that the interface is not at a target location within the channel, the controller controls a centrifugal separator and/or a pump system to move the interface to the target location.