You wish to perform a thermal effusivity measurement on your materials
Characterize a material's ability to absorb and release heat
Thermal effusivity is a thermophysical property that describes a material's ability to quickly absorb or release heat when exposed to a hot or cold source.
It depends on three fundamental quantities:
- thermal conductivity,
- specific heat capacity,
- the material's density.
The higher the effusivity, the more efficiently the material can exchange heat with its environment. Conversely, low effusivity characterizes insulating materials or materials with low thermal inertia.
Effusivity is therefore a key parameter for evaluating thermal comfort, a material's thermal responsiveness, and its heat dissipation performance.
Our technical resources for thermal effusivity measurement
Hot Disk Method
Obtain simultaneously the effusivity, thermal conductivity and heat capacity.
Hot Wire Method
The temperature variation allows us to calculate the effusivity.
Specific contact-thermal methods
To characterize thermal comfort or the sensation to the touch
The FILAB laboratory performs thermal effusivity measurements
In what context should a thermal effusivity measurement be performed?
Thermal effusivity measurement enables:
- optimization of tactile comfort (cosmetics, technical textiles),
- validation of insulating materials or heat sinks,
- qualification of materials for embedded electronics or heating systems,
- analysis of thermal behavior in medical devices,
- quality control of a modified formulation or a batch of material,
- study of the impact of ageing or environmental exposure,
- comparison of suppliers in a certification process.
Our laboratory thermal analysis services
From analysis to R&D, the FILAB laboratory offers multi-sector services to meet a wide range of thermal analysis requirements, including :
FAQ
Thermal effusivity represents a material's ability to rapidly absorb or release heat when in contact with a hot or cold source. It depends on conductivity, heat capacity, and density.
- Effusivity: a material's ability to exchange heat with its environment (contact).
- Diffusivity: the rate at which heat spreads within the material.
- Conductivity: the material's intrinsic ability to conduct heat. These properties are complementary and can be measured together for a complete understanding of thermal behavior.
Thermal effusivity is generally measured using transient methods that apply a thermal pulse to the material. The thermal response is then analyzed to determine the rate and magnitude of heat transfer.
Depending on the nature of the material, different techniques can be used:
Hot Disk Method (Transient Plane Source – TPS)
- A flat-plane probe generates a thermal pulse and records the material's response.
- This method allows for the simultaneous measurement of effusivity, thermal conductivity, and heat capacity.
- This method is well-suited for polymers, textiles, composites, foams, and porous or anisotropic materials.
Hot Strip or Hot Wire Method
- A linear heat source heats the material; the temperature change allows for the calculation of effusivity.
- This method is recommended for pastes, liquids, gels, or powders.
Specific Contact-Thermal Methods
- These methods are used to characterize thermal comfort or tactile sensation (cosmetics, textiles, and consumer goods industries).
The choice of method depends on the geometry, the nature of the material, and the target temperature range.
Yes, effusivity measurements can be complemented by:
- thermal conductivity,
- thermal diffusivity,
- specific heat capacity (DSC),
- TGA,
- chemical and microstructural characterization.
These combinations allow for a complete thermal understanding of the material.
