Temperature-controlled transport container and a method for controlling conditions in such container
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refrigeration systems for temperature-controlled transport containers face challenges in preventing frost formation, especially when maintaining temperatures close to or below zero degrees Celsius, which can lead to reduced cooling capacity and efficiency.
Innovation Solution
A refrigeration system with a closed air circuit separate from the cargo space, located outside and contiguous with at least one wall, and a pressurizing unit to establish a pressure difference between the closed air circuit and the ambient environment, minimizing the risk of frost formation without requiring a completely airtight or moisture-proof design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the refrigeration system maintains temperature close to or below zero degrees Celsius to cool the cargo space, then the cooling capacity is improved, but frost formation occurs on the heat exchanger surfaces
Solution Approach 1:
The patent divides the air circulation system into two separate circuits: a first air circuit for the cargo space and a second air circuit for the refrigeration unit. This segmentation prevents moisture-laden cargo space air from contacting the cold heat exchanger surfaces, eliminating frost formation while maintaining effective cooling of the cargo.
Solution Approach 2:
The patent extracts the refrigeration unit's air handling function from the cargo space environment by placing it in a separate enclosed space with its own dedicated air circuit. This isolation removes the source of moisture (cargo space air) from the frost-prone area (heat exchanger surfaces), resolving the contradiction between cooling effectiveness and frost prevention.
2Reliability
If the refrigeration system uses a separate airtight and moisture-proof cooling unit outside the cargo bay to prevent dehydration, then cargo space humidity is maintained, but frost build-up still occurs and the design becomes difficult and expensive
Solution Approach 1:
The patent uses pressurization of the second air circuit (refrigeration unit air circuit) relative to the first air circuit (cargo space) to create a pressure differential that prevents moisture migration. This pneumatic control mechanism stops humid air from entering the refrigeration unit where it could condense and freeze, eliminating frost build-up without requiring completely airtight construction.
Solution Approach 2:
The patent changes the pressure parameter of the second air circuit by introducing a pressurization device that maintains positive pressure relative to the cargo space. This pressure differential serves as a driving force to prevent moisture-laden air from migrating into the refrigeration unit, thereby preventing frost formation while allowing for practical, non-hermetic design.
3Object-affected harmful factors
If the refrigeration system lowers the temperature difference between air and heat exchanger to prevent frost, then frost formation is reduced, but cooling efficiency decreases
Solution Approach 1:
The patent extracts the air streams serving different functions into separate circuits: one for cargo space ventilation and one for heat exchange. This allows the heat exchanger to operate with optimal temperature difference for efficient cooling without concern for frost formation from cargo space humidity, while the cargo space air remains separate and does not contribute moisture to the heat exchange process.
4Productivity
If the refrigeration system increases the interaction area between air and heat exchanger to improve cooling, then cooling capacity is improved, but frost formation risk increases
Solution Approach 1:
The patent segments the air handling into separate circuits, allowing the second air circuit to provide extensive heat exchanger interaction area for maximum cooling capacity while using pressurization to prevent moisture-laden air from the cargo space from contaminating this large heat exchange surface, thereby eliminating frost formation risk.
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 solution effectively reduces the risk of frost formation, minimizes the need for defrosting, and maintains efficiency, even when operating on battery power, by controlling humidity and air pressure within the closed air circuit.
Implementation Method 1
a pressurizing unit for establishing a pressure difference between the closed air circuit and an ambient environment outside of, but in a vicinity of, the temperature-controlled transport container, wherein the pressure difference corresponds to a higher pressure in the closed air circuit than in the ambient environment
Implementation Method 2
at least one refrigeration unit configured to cool air in the closed air circuit
Implementation Method 3
The air inside a cargo space is heated by infiltration through the wall insulation if the ambient air outside the container is warmer
Data Source
AI summary
A temperature-controlled transport container (10) has a cargo space (1) for accommodating temperature-sensitive goods and a refrigeration system. The refrigeration system comprises a closed air circuit (2), separate from the cargo space and located outside of and contiguous with at least one wall (9) of the cargo space. The refrigeration system further comprises at least one refrigeration unit (5) configured to cool air in the closed air circuit. The refrigeration system also comprises a pressurizing unit (8) for establishing a pressure difference between the closed air circuit and the ambient environment (20) outside of, but in a vicinity of, the temperature-controlled transport container.