Air Conditioning Reheat Loop for Dehumidification Without Overcooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional air conditioning systems often cool indoor air below the target temperature during dehumidification, leading to inefficient energy use and the need for costly electric heaters to reheat the air.
Innovation Solution
An air conditioning system with an outdoor heat exchanger, an indoor heat exchanger, and a reheat heat exchanger, where the speed of an outdoor fan is adjusted to control the thermal energy extracted from the refrigerant, allowing dehumidified air to be reheated to a target temperature without excessive cooling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional dehumidification process is used with indoor heat exchanger, then moisture is removed from air, but air temperature drops below target temperature
Solution Approach 1:
The system divides the heat exchange process into separate stages: first dehumidification in the indoor heat exchanger, then reheat in the reheat heat exchanger. This segmentation allows independent optimization of each function - moisture removal without excessive cooling, followed by precise temperature restoration.
Solution Approach 2:
The reheat heat exchanger acts as an intermediary component between the indoor heat exchanger and the indoor space. It receives the over-cooled dehumidified air and restores it to the target temperature using refrigerant heat, preventing the harmful effect of excessive cooling while maintaining the dehumidification benefit.
2Temperature
If electric heaters are used to reheat air downstream of indoor heat exchanger, then air temperature is restored, but energy efficiency decreases and costs increase
Solution Approach 1:
The system uses the refrigerant's thermal energy - a resource already present in the closed loop - to provide the reheat function. Instead of importing external energy via electric heaters, the refrigerant itself serves the dual purpose of cooling (in the indoor heat exchanger) and reheating (in the reheat heat exchanger), making the system self-sufficient and energy-efficient.
Solution Approach 2:
The system recovers thermal energy from the refrigerant that would otherwise be wasted or require external input. The refrigerant absorbs heat during evaporation in the indoor heat exchanger and then releases this heat in the reheat heat exchanger, effectively recycling thermal energy within the system rather than discarding it or requiring additional energy input.
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 dehumidifies indoor air without lowering the temperature below the target level, improving energy efficiency and reducing the need for electric heating.
Implementation Method 1
an outdoor fan urges a flow of air through the outdoor heat exchanger to extract thermal energy from a refrigerant
Implementation Method 2
the coils pull moisture from the air by lowering the temperature of the air and causing moisture in the air to condense on the coils
Implementation Method 3
dehumidified air is reheated using thermal energy from a refrigerant in the reheat heat exchanger
Data Source
AI summary
An air conditioning system and a method of operating the same to dehumidify air from an indoor space without overly cooling that air is provided. The air conditioning system includes an outdoor heat exchanger, an indoor heat exchanger, and a reheat heat exchanger. Indoor air passes through the indoor heat exchanger where it is dehumidified before passing through the reheat heat exchanger where it is reheated using thermal energy from a refrigerant. An outdoor fan urges a flow of ambient air through the outdoor heat exchanger to extract thermal energy from the refrigerant before it passes to the reheat heat exchanger. The speed of the outdoor fan is adjusted to control an amount of thermal energy extracted from a refrigerant passing through the outdoor heat exchanger and thus the thermal energy supplied to the reheat heat exchanger for reheating the dehumidified air to a target temperature.