Guided Wave Radar Probe Retaining Elements for LNG Tank Level Gauging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radar level gauge systems face challenges in accurately measuring the filling level of low-reflectivity liquids like LNG and LPG due to signal loss and mechanical forces in large tanks, particularly in marine applications, where traditional still pipes are costly, complex, and prone to damage.
Innovation Solution
A guided wave radar level gauge system using a single conductor transmission line probe with mechanical retaining elements that allow vertical movement while restricting horizontal movement, reducing the risk of mechanical damage and signal interference, and eliminating the need for a still pipe.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a still pipe is used to focus electromagnetic signal energy for measuring low-reflectivity liquids, then measurement precision is improved, but device complexity and material usage increase
Solution Approach 1:
The patent extracts the essential function of signal focusing from the complex still pipe structure and implements it through a simple rod-shaped probe. The probe directly guides electromagnetic waves without requiring the additional components of a still pipe, thereby achieving signal focusing while reducing device complexity and material usage.
Solution Approach 2:
The patent replaces the mechanical still pipe structure with an electromagnetic field-based rod probe that performs the same signal guiding function. This substitution eliminates the need for complex mechanical support structures while maintaining the ability to focus electromagnetic energy on low-reflectivity liquid surfaces.
2Measurement precision
If a still pipe is used to enable measurement over large distances, then measurement capability is improved, but loss of substance and material cost increase
Solution Approach 1:
The patent employs a simple rod probe that uses minimal material compared to traditional still pipes. The probe is designed to be cost-effective and can be easily replaced if needed, reducing material costs while maintaining measurement capability over large distances through efficient electromagnetic wave guidance.
Solution Approach 2:
The patent changes the operational parameters of the probe by allowing it to move vertically within the tank. This movement capability enables the probe to maintain optimal positioning for signal transmission over varying liquid levels and distances, improving measurement capability without requiring additional materials or complex structures.
3Reliability
If the probe is allowed to move vertically to accommodate thermal expansion, then reliability is improved, but movement control becomes more difficult
Solution Approach 1:
The patent makes the probe dynamically movable along the rod-shaped support structure, allowing it to adjust its position vertically. This dynamic capability accommodates thermal expansion and contraction while maintaining reliable electrical connection through the flexible contact design, ensuring continuous operation under varying temperature conditions.
Solution Approach 2:
The probe automatically adjusts its vertical position in response to thermal expansion and contraction of the rod structure. The flexible electrical contact and movable design allow the probe to self-adjust without external intervention, maintaining reliable signal transmission while accommodating dimensional changes caused by temperature variations.
4Reliability
If retaining elements restrict horizontal movement of the probe, then reliability is improved, but the probe design becomes more complex
Solution Approach 1:
The patent segments the support structure into a vertical rod with multiple retaining elements spaced along its length. Each retaining element provides localized horizontal constraint at specific positions, allowing the probe to be stabilized at multiple points without requiring a complex continuous support structure. This segmentation approach improves reliability while maintaining simple probe design.
Solution Approach 2:
The retaining elements act as intermediary components between the rod structure and the probe. These elements provide the necessary horizontal constraint to the probe without requiring direct integration into the probe itself, thereby improving reliability while keeping the probe design simple and modular.
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 measurement accuracy and reliability by minimizing signal loss and mechanical stress on the probe, reducing material usage, and simplifying the support structure, while allowing for flexible probe configurations and easy installation.
Implementation Method 1
a surface waveguide comprising a single conductor transmission line probe, connected to the transceiver, arranged extending vertically into the tank and configured to guide the electromagnetic transmission signals towards the surface and to guide the reflected electromagnetic signals back to the transceiver
Implementation Method 2
a plurality of retaining elements arranged in fixed positions in relation to an inside of the tank and spaced apart along the probe, wherein each of the retaining elements circumscribes the probe, and is configured to allow movement of the probe in a vertical direction relative the retaining element, and to restrict movement of the probe in a horizontal direction relative the retaining element
Implementation Method 3
Determination of the distance can for example be based on time of flight of the received reflected signals
Implementation Method 4
The transmitted electromagnetic signals are reflected at the surface of the product, and the reflected signals are received by a receiver or transceiver comprised in the radar level gauge system
Data Source
Figure 1
Figure 2~3
Figure 4A~4B
AI summary
A GWR level gauge system for determining a filling level in a tank. The system comprises a tank, a transceiver, a surface waveguide comprising a single conductor transmission line probe, connected to the transceiver, arranged extending vertically into the tank and configured to guide the electromagnetic transmission signals towards the surface and to guide the reflected electromagnetic signals back to the transceiver; processing circuitry connected to the transceiver and configured to determine the filing level based on received reflected electromagnetic signals; a plurality of retaining elements arranged in fixed positions in relation to an inside of the tank and spaced apart along the probe, wherein each of the retaining elements circumscribes the probe, and is configured to allow movement of the probe in a vertical direction relative the retaining element, and to restrict movement of the probe in a horizontal direction relative the retaining element.