Aerogel is a lightweight, low-density material made from silica gel, which has no liquid in it and is eventually replaced by gas. This low thermal conductivity, as well as high insulation capacity, can be attributed to the presence of small, air-filled nanopores (97% of the material), as well as small, dispersed silica solid blobs (the remaining 3%). Aerogel itself is extremely fragile, but it is a flexible, high-tech insulating material that can be used for many purposes, such as aerospace, construction, clothing and plumbing.

Aerogel felt is a new kind of thermal insulation material, which is composed of nano-silica aerogel and glass fiber wool or pre-oxidized fiber felt by special process. Aerogel felt combines the low thermal conductivity of aerogel with the flexibility of the fiber, so will the thermal conductivity of aerogel felt change?
1, how to measure the thermal conductivity of aerogel felt
In this experiment, we will use the heat flux meter (HFM) to measure the thermal conductivity of the aerogel felt. The purpose of this experiment was to confirm the accuracy and precision of the reported thermal tests while discovering the tremendous thermal properties of aerogel felt. HFM has a reporting accuracy of 0.5% and a reported measurement accuracy of 3%.
2. Heat conduction test of aerogel felt
To test the thermal conductivity of the aerogel felt, the aerogel felt was placed inside the HFM housing. Then set the parallel plate to automatically adjust the height of the specimen. When four digital encoders, one for each upper plate Angle, automatically adjust the method for sample thickness measurement at their respective positions. The average of these thicknesses is then calculated and the upper plate is pressed to the calculated thickness of the specimen. Parallel plates on both sides of the sample are then used to establish a steady unidirectional heat flow through an aerogel blanket at constant but different temperatures (measured at 10 ° C and 30 ° C). This temperature plate difference is set up to simulate heat loss from a warm internal environment to a colder external environment and vice versa.
Prior to testing the aerogel thermal conductivity, a preliminary test was performed on a selected standard to calibrate the heat flow sensor. To calculate the thermal conductivity (VOT), the calibration values of the heat flow sensor, plate temperature records, and plate separation measurements are entered into Fourier's law of thermal conductivity: λ=j·d/ΔT.

3. Thermal conductivity of aerogel felt
Aerogel felt displays a thermal conductivity reading of 0.024W/MK at 20 ° C. Since the thermal conductivity of aerogels is very low, it is possible to isolate sensitive environments from harsh environments, such as low or high temperatures. At present, the main use of aerogel felt is for building insulation applications in industrial and commercial buildings. Aerogel felt can not only improve the energy efficiency of buildings, but also, due to their thin and flexible nature, they can greatly reduce the thickness of the building envelope.
Aerogel felt has the characteristics of low thermal conductivity, tensile strength and compressive strength, which is a flexible thermal insulation felt, mainly used in industrial pipelines, storage tanks, industrial furnace bodies, power plants, buildings and other fields of thermal insulation.