Single-Needle Sap Flow Sensing With Minimal Xylem Damage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sap flow measurement technologies cause excessive damage to xylem tissues and are costly due to the need for multiple sampling points and layers of temperature sensors, making them inaccurate and inefficient.
Innovation Solution
A single needle sap flow sensor with a heat source and thermal sensor is used, providing heat energy to create steady-state temperature rises under both no-flow and flow conditions, allowing for the determination of sap flow rate based on the total heat energy and time required to achieve these rises, thereby minimizing tissue damage and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple layers of temperature sensors are used, then measurement precision is improved, but device complexity and thickness increase
Solution Approach 1:
The patent combines heating elements and temperature sensors into a single integrated needle structure, eliminating the need for multiple separate sensor layers. This merging approach maintains measurement capability while significantly reducing structural complexity and thickness.
Solution Approach 2:
The single needle structure serves multiple functions: it acts as both the heating element and the sensing probe. By making the needle itself multi-functional, the patent eliminates the need for separate temperature sensor layers, thereby reducing device complexity while maintaining measurement precision.
2Measurement precision
If multiple sampling points are used, then measurement precision is improved, but damage to xylem tissues increases
Solution Approach 1:
The patent merges multiple sampling functions into a single needle insertion point. By integrating all measurement capabilities into one probe, the system achieves accurate sap flow measurement while requiring only one puncture in the tree trunk, thereby minimizing damage to xylem tissues.
Solution Approach 2:
The patent transitions from a multi-point spatial sampling approach to a single-point multi-parameter measurement approach. By measuring temperature at multiple positions along the single needle rather than using multiple needles, the system achieves the same measurement precision with minimal tissue damage.
3Measurement precision
If multiple layers of temperature sensors are used, then measurement precision is improved, but manufacturing cost increases
Solution Approach 1:
The patent combines heating and sensing functions into a single needle structure, eliminating the need to manufacture and assemble multiple separate sensor layers. This integration simplifies the manufacturing process and reduces material costs while maintaining measurement precision.
Solution Approach 2:
The single needle structure performs both heating and temperature sensing functions, eliminating the need for separate temperature sensor layers. This multi-functionality approach reduces component count and manufacturing complexity, thereby lowering production costs while maintaining measurement accuracy.
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 approach enables accurate and efficient measurement of sap flow velocity without causing significant damage to trees, reducing costs and improving measurement accuracy, as demonstrated by correlations with continuous gravimetric and lysimeter measurements.
Implementation Method 1
provide first heat energy by the heating elements to produce a first pre-determined temperature rise thereby producing a no-flow thermal plume
Implementation Method 2
a needle, comprising a plurality of heating elements and a temperature sensor disposed on a single plane
Data Source
AI summary
A method for determining sap flow velocity, constituted of: providing a heat source and a thermal sensor on a single needle: at a no-flow condition, providing first heat energy to produce a steady state first pre-determined temperature rise: determining a total amount of first heat energy provided to produce the first pre-determined temperature rise: at a flow condition: providing second heat energy to produce a steady state second pre-determined temperature rise: determining a total amount of second heat energy provided to produce the second pre-determined temperature rise: and determining a sap flow rate responsive to the determined total amount of first heat energy and the determined total amount of second heat energy.