Variable-SDR Geothermal Probe Pipe for Deep Pressure Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Geothermal probe pipes face challenges in withstanding pressure loads at deep locations due to geological conditions, leading to potential cavity formation and reduced operational safety, while reducing the Standard Dimension Ratio (SDR) is not feasible as it increases flow resistance and decreases heat transfer.
Innovation Solution
The geothermal probe design features a constant SDR value in the first longitudinal section and a decreasing SDR value in the second longitudinal section, allowing the pipe to adapt to increasing hydrostatic pressure with depth, ensuring operational safety and maintaining heat transfer efficiency by limiting wall thickness to the minimum required for stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the SDR value is reduced to withstand higher pressure at deep locations, then pressure resistance is improved, but flow resistance increases and heat transfer decreases
Solution Approach 1:
The pipe is divided into two longitudinal sections with different SDR values. The first section (upper part) has a constant SDR value of approximately 11 optimized for heat transfer and flow, while the second section (lower part) has a reduced SDR value to withstand higher hydrostatic pressure at depth. This local differentiation allows each section to be optimized for its specific functional requirements without compromising the other.
Solution Approach 2:
The geothermal probe pipe is segmented into two distinct longitudinal sections along its length. The first longitudinal section extends from the first end to a first distance, and the second longitudinal section extends from the first end to a second distance greater than the first distance. This segmentation enables the pipe to have different wall thickness characteristics in different regions, allowing it to withstand varying pressure conditions at different depths while maintaining optimal flow and heat transfer properties in the upper section.
2Strength
If the SDR value is reduced to withstand higher pressure at deep locations, then pressure resistance is improved, but heat transfer decreases
Solution Approach 1:
The pipe is divided into two longitudinal sections with different SDR values. The first section (upper part) has a constant SDR value of approximately 11 optimized for heat transfer and flow, while the second section (lower part) has a reduced SDR value to withstand higher hydrostatic pressure at depth. This local differentiation allows each section to be optimized for its specific functional requirements without compromising the other.
3Strength
If the wall thickness is increased to withstand higher pressure, then pressure resistance is improved, but flow resistance increases
Solution Approach 1:
The pipe is divided into two longitudinal sections with different SDR values. The first section (upper part) has a constant SDR value of approximately 11 optimized for heat transfer and flow, while the second section (lower part) has a reduced SDR value to withstand higher hydrostatic pressure at depth. This local differentiation allows each section to be optimized for its specific functional requirements without compromising the other.
Solution Approach 2:
The geothermal probe pipe is segmented into two distinct longitudinal sections along its length. The first longitudinal section extends from the first end to a first distance, and the second longitudinal section extends from the first end to a second distance greater than the first distance. This segmentation enables the pipe to have different wall thickness characteristics in different regions, allowing it to withstand varying pressure conditions at different depths while maintaining optimal flow and heat transfer properties in the upper section.
4Strength
If the wall thickness is increased to withstand higher pressure, then pressure resistance is improved, but heat transfer decreases
Solution Approach 1:
The pipe is divided into two longitudinal sections with different SDR values. The first section (upper part) has a constant SDR value of approximately 11 optimized for heat transfer and flow, while the second section (lower part) has a reduced SDR value to withstand higher hydrostatic pressure at depth. This local differentiation allows each section to be optimized for its specific functional requirements without compromising the other.
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 design enables safe operation of geothermal probe systems down to 320 m depth with improved energy balance and minimal impairment to flow resistance and heat transfer properties, ensuring high operational reliability even without counteracting external pressure.
Implementation Method 1
the heat carrier is heated by the geothermal heat conducted through the pipe wall
Implementation Method 2
the hydrostatic pressure of the heat carrier acting on the pipe wall increases with increasing depth
Data Source
Figure 1
AI summary
The tube (2) has an end (4), and another end (6) arranged at a distance from the former end around the length of the tube. The latter end is lowered into soil. A longitudinal section (8) is turned towards the former end, and another longitudinal section (10) is connected to the former longitudinal section. Standard dimension ratio value of the tube is calculated based on equation relating to tube outer diameter (da) and tube wall thickness, where the value is constant over the length of the former longitudinal section and decreases towards the latter end.