Thermodynamic Engine Using Multi-Boiling Point Fluid Mixture

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing thermodynamic engines, such as Organic Rankine Cycle engines, face inefficiencies in converting thermal energy to mechanical work due to the limitations of single-component working fluids, particularly in the phase changes and heat transfer mechanisms.

Innovation Solution

Employing a mixture of miscible fluids with different boiling points in a closed working-fluid circuit, where one fluid fully vaporizes and the other transfers heat energy through latent condensation, enhancing work production in the expander.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single-component working fluid is used in Organic Rankine Cycle engines, then the system structure is simple, but the efficiency of converting thermal energy to mechanical work is limited

Engineering Contradiction:
Improvesystem structureVSAvoidefficiency of converting thermal energy to mechanical work
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The patent employs a composite working fluid consisting of multiple components with different boiling points (e.g., refrigerant 123 and refrigerant 114) to replace single-component working fluids. This composite approach enables the fluid to utilize both vaporization heat and condensation heat of different components, thereby improving thermal energy conversion efficiency while maintaining relatively simple system structure.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent exploits phase transitions of multiple components with different boiling points within the working fluid mixture. During the expansion process, components with lower boiling points vaporize first, releasing vaporization heat, while components with higher boiling points condense later, releasing condensation heat. This multi-stage phase transition mechanism significantly enhances the conversion of thermal energy to mechanical work.

Inventive Principle:
Principle #36Phase transitions

2Device complexity

If conventional single-phase working fluids are used, then the heat transfer mechanism is simple, but the work output in the expander is limited

Engineering Contradiction:
Improveheat transfer mechanismVSAvoidwork output in the expander
Core Design Contradiction:
Device complexityVSPower

Solution Approach 1:

The patent implements a two-phase working fluid system where both vaporization and condensation phase transitions occur within the expander. The mixture of components with different boiling points enables simultaneous or sequential phase changes, allowing the system to capture both vaporization heat (endothermic) and condensation heat (exothermic), thereby significantly increasing the work output compared to single-phase fluids.

Inventive Principle:
Principle #36Phase transitions

Solution Approach 2:

By using a composite working fluid with multiple components having different thermodynamic properties, the patent creates a system that can perform multiple heat transfer functions within a single phase change process. This composite approach enables enhanced heat transfer mechanisms that directly translate to higher work output in the expander.

Inventive Principle:
Principle #40Composite materials

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 significantly improves efficiency by maintaining the vapor phase of one fluid and utilizing latent heat transfer from the other, thereby increasing the overall work output.

Implementation Method 1

a heater for vaporising working fluid pumped to it from the pump means and feeding the vaporised working fluid to the expander

Methodology Applied
Scientific EffectVaporization: Evaporation

Implementation Method 2

a condenser downstream of the expander for condensing expanded vaporised working fluid exhausting from the expander

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 3

vapour and/or liquid of the higher boiling point fluid releases heat energy in the expander to vapour of the lower boiling point constituent fluid for production of work in the expander

Methodology Applied
Scientific EffectLatent heat transfer: Latent Heat

Data Source

PatentEP3911844B1engine
Publication Date: 2025.07.09 GAS EXPANSION MOTORS LTD
  • EP3911844B1 patent drawingFigure 1
  • EP3911844B1 patent drawingFigure 2
  • EP3911844B1 patent drawingFigure 3

AI summary

An externally heated thermodynamic engine has a closed working-fluid circuit. The engine has a thermodynamic expander (21) for extracting work from a vaporised working fluid (22) that is fed to a feed for it. There is also a condenser (26) downstream of the expander for condensing expanded vaporised working fluid that is exhausting from the expander. A liquid tank (28) is downstream from the condenser, and pump means (29) is located downstream from the liquid tank for pumping out condensed working fluid (38). Further, there is a means for heating (50) and at least partially vaporising working fluid pumped to it from the pump and feeding the heated working fluid to the expander. The heating means itself has at least one inlet for the working fluid pumped to it, and at least one output from which the working fluid is fed to the expander. The engine is adapted and arranged for operation with a working fluid, with the working fluid itself including at least two different boiling point constituent fluids. The pump means is adapted to pump, from the liquid tank to the heating means, both the different boiling point constituent fluids in a determined ratio as liquids, whereby, in use, on feeding of the working fluid to the expander in at least partially vaporised state the vapour and/or liquid of the higher boiling point liquid releases energy in the expander to the vapour of the lower boiling point constituent fluid for production of work in the expander.