36 Phase transitions
Use phenomena occurring during phase transitions (e.g. volume changes, loss or absorption of heat, etc.).
• Water expands when frozen, unlike most other liquids. Hannibal is reputed to have used this when marching on Rome a few thousand years ago. Large rocks blocked passages in the Alps. He poured water on them at night. The overnight cold froze the water, and the expansion split the rocks into small pieces which could be pushed aside.
• Heat pumps use the heat of vaporization and heat of condensation of a closed thermodynamic cycle to do useful work.
• Water expands when frozen, unlike most other liquids. Hannibal is reputed to have used this when marching on Rome a few thousand years ago. Large rocks blocked passages in the Alps. He poured water on them at night. The overnight cold froze the water, and the expansion split the rocks into small pieces which could be pushed aside.
• Heat pumps use the heat of vaporization and heat of condensation of a closed thermodynamic cycle to do useful work.
Is this principle frequently used?
This principle is rarely used with 60 instances in the matrix.This principle is proposed to solve the following contradictions:
Click on a contradiction to explore it
1/11 1/21 1/32 1/36 5/11 5/37 6/10 6/11 6/29 6/36 7/10 7/11 7/23 9/17 10/3 10/6 10/8 10/20 10/25 10/26 10/29 10/31 10/37 11/1 11/3 11/5 11/6 11/9 11/10 11/22 11/23 11/25 11/26 11/37 12/26 16/17 17/1 17/9 17/16 17/23 20/10 20/27 21/1 21/10 22/10 23/7 23/11 23/17 25/10 25/11 26/11 27/20 29/6 29/10 29/30 32/2 36/1 36/6 37/11 39/10
The colour indicates the ranking of the proposed principle to solve the contradiction:
1st,
2nd,
3rd,
4th.
This ranking reflects the frequency of occurrence of the principle in the analysed patents for this type of contradiction.
When a principle appears in first position, it means that it is statistically the most used in the patents studied for this type of problem.