Test chamber
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing test chambers face challenges in achieving low temperatures below −80°C while being environmentally friendly and safe, as they require refrigerants that do not contribute to ozone depletion or global warming, and are non-flammable, which complicates design and operation, and carbon dioxide is unsuitable due to its triple point temperature.
Innovation Solution
A test chamber using a nearly azeotropic or zeotropic refrigerant mixture of carbon dioxide with components like ethane, ethene, hexafluoroethane, pentafluoroethane, and propane, which has a low CO2 equivalent and allows for a temperature range of −80°C to +180°C, avoiding flammability issues and enabling cost-effective design without additional safety precautions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If carbon dioxide is used as refrigerant, then environmental friendliness is improved, but temperature range below −55°C cannot be achieved
Solution Approach 1:
The patent uses composite refrigerant mixtures combining carbon dioxide with other substances (such as hydrocarbons or fluorinated compounds) to achieve both environmental friendliness and the required temperature range below −80°C. This composite approach allows the refrigerant to overcome the limitations of pure carbon dioxide while maintaining low GWP.
2Temperature
If flammable refrigerants are used, then temperature control performance is improved, but safety measures and production costs increase
Solution Approach 1:
The patent changes the chemical composition parameters of the refrigerant to achieve non-flammable properties while maintaining effective temperature control performance. By selecting specific refrigerant mixtures with appropriate flammability ratings, the system avoids the need for additional safety measures and associated costs.
3Temperature
If dinitrogen monoxide is used in carbon dioxide mixture, then temperature below −70°C is achieved, but ozone layer damage occurs
Solution Approach 1:
The patent extracts and removes dinitrogen monoxide from the refrigerant mixture due to its ozone-depleting properties. Instead, it uses alternative substances that do not harm the ozone layer, thereby eliminating the harmful effect while preserving the low-temperature capability through proper refrigerant formulation.
4Ease of operation
If mobile test chamber design is used, then flexibility and mobility are improved, but all temperature control modules must be integrated into the unit
Solution Approach 1:
The patent merges all temperature control modules including compressor, condenser, expansion device, and evaporator into a single integrated mobile unit. This consolidation enables the test chamber to be transported and deployed flexibly while maintaining complete temperature control functionality within the mobile structure.
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
The refrigerant mixture allows for efficient temperature control within the specified range with minimal environmental impact, simplifying shipping, operation, and design, and maintaining temperature constancy during tests, while avoiding the need for flammability sensors and safety measures.
Implementation Method 1
a heat exchanger disposed in the test space
Implementation Method 2
a compressor
Implementation Method 3
a condenser
Implementation Method 4
an expansion element
Implementation Method 5
which is temperature-insulated
Data Source
AI summary
A test chamber (10) for conditioning air has a test space (12), and a temperature control device (11) for controlling the temperature of the test space and allowing a temperature in a range of −80° C. to +180° C., preferably −100° C. to +200° C., to be established within the test space, the temperature control device having a cooling device (16) with a cooling circuit (17), a heat exchanger (18), a compressor (19), a condenser (20), and an expansion element (21), wherein the refrigerant is a nearly azeotropic and/or zeotropic refrigerant mixture of a mass percentage of carbon dioxide and a mass percentage of at least one of the components ethane, ethene, hexafluoroethane, pentafluoroethane, monofluoro-ethane, 1,1-difluoroethene, fluoromethane and/or propane and/or xenon, the refrigerant having a relative CO2 equivalent of <3000, preferably <500, in particular preferably <10, with respect to 20 years.