GB/T 45362-2025 Textiles - Determination of thermal effusivity of fabrics - Modified transient plane source method
1 Scope
This document describes a method for testing the thermal effusivity of fabrics using the modified transient plane source.
This document is applicable to woven fabrics, knitted fabrics, and non-woven fabrics, and may serve as a reference for fabrics containing fillers.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3820 Determination of thickness of textiles and textile products
GB/T 6529 Textiles - Standard atmospheres for conditioning and testing
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
modified transient plane source; MTPS
device which has a single-sided plane heat source and a heating protection ring mounted perpendicular to the plane heat source and can cause an instantaneous heat pulse to enter a specimen by contacting one side of the specimen
3.2
thermal effusivity
parameter used to characterize the capacity of one material to exchange heat when in contact with another material
Note: The equation of definition of thermal effusivity is shown in Equation (1):
(1)
where,
e——the thermal effusivity of a material, W/(m2K);
λ——the thermal conductivity of the material, W/(mK);
cp——the specific heat capacity of the material, J/(kgK);
ρ——the density of the material, kg/m3.
4 Principle
A constant current is applied to the heating element of a sensor so that a small amount of heat is provided and transferred to the specimen unidirectionally. The temperature increase of the contact surface between the specimen and the sensor causes the voltage change of the sensor. The heating rate is determined by the relationship curve between the voltage change of the sensor and the test time, and used to calculate the thermal effusivity of the specimen.
Contents Foreword 1 Scope 2 Normative references 3 Terms and definitions 4 Principle 5 Apparatus 6 Specimen preparation 7 Standard atmospheres for conditioning and testing 8 Test procedures 9 Result calculations 10 Test report
