Cryogenic Engine Coupled Refrigeration for Reduced Energy Consumption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current vehicle transport refrigeration systems are inefficient, leading to high greenhouse gas emissions and excessive hydrocarbon fuel consumption, due to over-specification and the need for continuous cooling, which results in low coefficients of performance and significant energy wastage.
Innovation Solution
A cryogenic engine system is thermally coupled with a refrigeration system via a heat exchange system, where the cryogenic engine acts as a heat sink, using the refrigeration system's heat to expand the working fluid and enhance efficiency, allowing for downsizing of the refrigeration system and direct use of cryogenic fluids for fast temperature control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a standard closed loop refrigeration system is used with over-specified power, then the cooling capacity is sufficient to meet the heat transfer requirements, but the coefficient of performance is low and energy consumption is high
Solution Approach 1:
The patent combines the refrigeration system with a cryogenic engine system, merging two separate systems into one integrated unit. The heat rejected by the refrigeration system is used to warm the cryogenic working fluid before expansion, and the cryogenic engine's cooling capacity supplements the refrigeration system. This merging allows the systems to support each other, reducing the need for over-specification and improving overall energy efficiency.
Solution Approach 2:
The integrated system performs multiple functions: the refrigeration system provides cooling, the cryogenic engine provides additional cooling capacity, the cryogenic engine generates power through expansion, and the heat exchange system transfers thermal energy between components. This multi-functionality reduces the need for separate systems and improves overall efficiency by utilizing waste heat and reducing over-specification.
2Reliability
If the refrigeration unit is over-specified to handle peak cooling demands, then the cooling requirement is met, but the unit runs at inefficient points during normal operation
Solution Approach 1:
The system dynamically adjusts the contribution of each cooling source based on demand. The cryogenic engine's cooling capacity can be modulated by controlling the expansion rate of the working fluid, and the heat exchange system dynamically transfers heat between the refrigeration system and cryogenic engine. This dynamic operation allows the system to meet peak demands reliably while operating efficiently during normal conditions.
Solution Approach 2:
The cryogenic engine uses the heat rejected by the refrigeration system to warm its working fluid before expansion, converting waste heat into useful work and additional cooling capacity. This self-service mechanism allows the system to improve its own efficiency without external input, reducing the need for over-specification while maintaining reliability.
3Speed
If cryogenic fluid is used directly for cooling, then fast temperature control is achieved, but asphyxiation hazards and inefficiency occur
Solution Approach 1:
The patent uses a heat exchange system as an intermediary between the cryogenic engine and the refrigeration system. Instead of directly spraying cryogenic fluid into the compartment (which creates asphyxiation hazards), the cryogenic engine's cooling effect is transferred through controlled heat exchange. This intermediary approach maintains the fast temperature control benefits of cryogenic systems while eliminating the direct contact hazards.
4Power
If existing cryogenic systems use independent power sources, then cooling is provided, but the system complexity and cost increase
Solution Approach 1:
The patent merges the power generation function with the cooling function by integrating the cryogenic engine into the refrigeration system. The cryogenic engine generates power through the expansion of its working fluid, and this power can be used to drive the refrigeration system's compressor or other components. This eliminates the need for independent power sources, reducing system complexity and cost while maintaining cooling power.
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 configuration reduces energy consumption, emissions, and weight penalties, while providing efficient and safe cooling by leveraging the cryogenic fluid's benefits, achieving improved refrigeration performance and reduced fuel usage.
Implementation Method 1
heat generated by the refrigeration system is used to expand working fluid in the cryogenic engine system
Implementation Method 2
working fluid in the cryogenic engine system acts as a heat sink for removing heat from the refrigeration system
Data Source
AI summary
A system comprising a cryogenic engine system and a refrigeration system, wherein the cryogenic engine system and the refrigeration system are mechanically and/or thermally coupled with each other. The refrigeration system is driven by the cryogenic engine system and the cryogenic engine system enhances cooling of the refrigeration system.