Thermochromic Window with Hydrogel Layer for Dynamic Emissivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current intelligent windows lack the ability to dynamically adjust intermediate infrared emissivity, leading to increased heating energy consumption in winter and inefficient energy savings, as most radiative cooling materials have low transmittance and fixed emissivity properties.
Innovation Solution
A thermochromic intelligent window with a metal oxide coating and a hydroxypropyl cellulose hydrogel layer, where the hydroxypropyl cellulose hydrogel layer is wrapped between two polyethylene layers, allowing for adjustable solar transmittance and intermediate infrared emissivity based on temperature changes, enabling reversible operation for summer and winter conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If radiative cooling materials are used to reduce intermediate infrared emissivity, then cooling effect is improved, but transmittance decreases and heating energy consumption increases in winter
Solution Approach 1:
The patent applies thermochromic materials that dynamically change their optical properties in response to temperature changes. When temperature rises above a transition point, the material changes from high-transmittance/low-emissivity state to low-transmittance/high-emissivity state, enabling automatic adaptation to seasonal changes without external control
Solution Approach 2:
The patent changes the physical and chemical parameters of the window material by using thermochromic substances that alter their transmittance and emissivity characteristics based on temperature. This allows the window to transform from a static component to a dynamic system that optimizes energy performance across different thermal conditions
2Use of energy by moving object
If thermochromic materials are used to adjust solar transmittance, then solar modulation capability is improved, but intermediate infrared emissivity switching capacity is insufficient
Solution Approach 1:
The patent combines thermochromic materials with specific polymer matrices and additives to create a composite material system. This composite structure enables simultaneous control of both solar transmittance and intermediate infrared emissivity, overcoming the limitations of single-material approaches
3Loss of energy
If window transmittance is reduced to prevent heating, then cooling energy consumption is reduced, but natural lighting and visibility are compromised
Solution Approach 1:
The patent applies different functional layers with specialized properties at different locations within the window structure. The thermochromic layer is positioned to selectively modulate solar radiation while maintaining visibility, creating local optical quality variations that simultaneously achieve cooling reduction and lighting preservation
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 window effectively reduces indoor temperature, saves energy consumption, and minimizes cooling and heating loads by dynamically adjusting heat radiation and sunlight transmittance according to seasonal changes, achieving a temperature drop of up to 30°C in summer and maintaining warmth in winter.
Implementation Method 1
the hydroxypropyl cellulose hydrogel layer has a good solar modulation capability. The hydroxypropyl cellulose hydrogel layer below its transformation temperature is very high in transparency and sunlight can penetrate the window smoothly. Once the temperature exceeds its transformation temperature, the hydroxypropyl cellulose hydrogel layer becomes non-transparent and blocks the sunlight.
Implementation Method 2
the metal oxide coating has a low-emission function in the intermediate infrared region
Implementation Method 3
a first rotating shaft is assembled on an upper portion of the window frame, a second rotating shaft is assembled on a lower portion of the window frame, and the window frame can rotate positively and negatively about the first rotating shaft and the second rotating shaft.
Data Source
AI summary
Disclosed is a thermochromic intelligent window with an adjustable emissivity. The thermochromic intelligent window includes a window frame. A glass assembly is assembled in the window frame and includes a glass substrate. One side of the glass substrate is deposited with a metal oxide coating for adjusting the glass substrate, the metal oxide coating has a low-emission function, and the metal oxide coating is a layer of transparent indium tin oxide film. A solar-adjusted high-emission portion is assembled on the other side of the glass substrate and includes a first polyethylene layer. A hydroxypropyl cellulose hydrogel layer is assembled on an upper portion of the first polyethylene layer. A second polyethylene layer is further assembled on the hydroxypropyl cellulose hydrogel layer. The hydroxypropyl cellulose hydrogel layer is wrapped between the first polyethylene layer and the second polyethylene layer.