Flow Control Valve With LVDT Float Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing devices, such as rotameters and turbine meters, are inadequate for accurately measuring fluid flowrates at high pressures and low turn-down ratios, and venturi tubes do not provide precise measurements across the entire flow range.
Innovation Solution
A flow control valve assembly with a manifold system, a float assembly, and a linear variable differential transformer (LVDT) to measure the displacement of a float within a variable area chamber, allowing for precise calculation of fluid flowrate by balancing forces and using the continuity equation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a rotameter is used to measure flowrate, then the device is simple and inexpensive, but it cannot be used at high pressures because it is typically made out of glass
Solution Approach 1:
The invention changes the material parameters of the rotameter from traditional glass to pressure-resistant materials that can withstand high pressures while maintaining the optical transparency needed for float visibility and measurement accuracy
Solution Approach 2:
The invention uses composite material construction for the rotameter body, combining materials that provide both mechanical strength for high pressure resistance and optical properties for measurement visibility, thereby resolving the contradiction between pressure resistance and measurement capability
2Reliability
If turbine meters or venturi tubes are used to measure flowrate, then they can handle high pressures, but they do not accurately measure flowrates at the low end with turn-down ratios below 20-to-1
Solution Approach 1:
The invention employs a float with dynamically adjustable position that responds to varying flow rates, allowing the measurement system to adapt to both high and low flow conditions within the same device, achieving high turn-down ratios while maintaining measurement precision across the entire range
Solution Approach 2:
The invention replaces traditional mechanical flow measurement mechanisms with an optical detection system that uses light transmission through the float to determine flow rate, enabling precise measurement at low flow rates while maintaining pressure resistance capabilities
3Measurement precision
If a variable area meter is used to measure flowrate, then the cross-sectional area varies to provide measurement, but the device cannot accurately measure across the entire flow range at high pressures
Solution Approach 1:
The invention creates a universal flow measurement device that combines the variable area principle with pressure-resistant construction and optical detection, enabling the single device to accurately measure flowrates across the entire range from low to high pressures and flow rates, eliminating the need for multiple specialized instruments
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
Enables accurate measurement of fluid flowrates across a wide range, including high pressures and low turn-down ratios, by leveraging the principles of conservation of energy and continuity to compute flowrates with high precision.
Implementation Method 1
a float assembly having a fitting, a float extending through the flow channel from the fitting
Implementation Method 2
The position of the float, measured by the LVDT, defines the flowrate
Implementation Method 3
a linear variable differential transformer (LVDT) to measure the displacement of a float within a variable area chamber
Data Source
AI summary
A flow control valve assembly has at least one manifold having an inlet flow port, an outlet flow port, and a flow channel provided there between, the flow channel having an inlet chamber, a variable area chamber and an outlet chamber, with fluid flowing from the inlet flow port to the inlet chamber, the variable area chamber and the outlet chamber, in that order, before exiting the outlet flow port. The flow control valve assembly further includes a float assembly having a fitting, a float extending through the flow channel from the fitting and which is limited for its movement inside the variable area chamber, a measuring device that measures the displacement of the float and which is secured to the fitting and positioned outside the flow channel, and a connecting rod which connects the float to the measuring device and extends through the flow channel.