The Review of Some Commonly Used Methods and Techniques to Measure the Thermal Conductivity of Insulation Materials

Abstract

The use of insulation materials is considered as one of the most effective means of conserving energy in various fields. Thermal insulation materials enable systems to achieve energy efficiency. Many different thermal insulation materials have been developed to reduce heat flow by limiting conduction, convection, and/or radiation while performing one or more functions. These functions may vary in the context of thermal design, numerical simulations, and a wide range of engineering problems, such as determining the heat loss, temperature field, isolation, and cooling conservation, and in a variety of other technologies. One of the most effective ways to identify and determine performance is effective thermal conductivity. The thermal measurement performance is usually evaluated in a temperature and signal gradient for single or combined homogeneous/heterogenous materials. The two main categories of thermal conductivity measurement techniques are steady-state methods and transient methods. The aim of this chapter is to present various measurement methods and to investigate their suitability for method purposes. This chapter presents new and accurate experimental techniques and methods for measuring the thermal conductivity of several most commonly used insulation materials. Some of these methods are commonly used in the field for measuring the thermal property of insulation materials. On the other hand, different insulation measurement practices are presented depending upon the overall structures. The analysis predicting the thermal conductivities of insulation materials is also discussed.

Polystyrene nanofibers for nonwoven porous building insulation materials

“…To highlight the advantage of the fibrous morphology of electrospun waste‐PS materials for applications such as building insulation, we investigated their thermal transport properties as freestanding materials and in the sandwich structures between different building materials. Several experimental techniques have been used to evaluate the thermal conductivity in insulation materials . However, evaluation of the insulation potential in the electrospun nanofiber sheets is a great challenge, due to their sensitivity to pressure, which modifies the porosity and packaging nanofibers in the material.…”

“…Several experimental techniques have been used to evaluate the thermal conductivity in insulation materials. 60,61 However, evaluation of the insulation potential in the electrospun nanofiber sheets is a great challenge, due to their sensitivity to pressure, which modifies the porosity and packaging nanofibers in the material. In general, researchers mainly focus on the thermal conductivity measurements along the individual fiber length, showing extremely high thermal conductivity when compared to bulk materials.…”

Comparison of Ablation Resistance and Thermal Conductivity of C-Ph and Cnt Composite Laminates

“…[5] G. Sravanthi and team had conducted an investigation on ablative properties of C-Ph and C-Ph coated with zirconia. [7] EXPERIMENTAL INVESTIGATIONS TO DETERMINE THERMAL…”

Temperature Diffusivity Measurement and Nondestructive Testing Requiring No Extensive Sample Preparation and Using Stepwise Point Heating and IR Thermography

“…Modern thermographic methods employing mathematical models and thermogram analysis techniques developed in recent years allow extracting a lot of useful information about the state of various objects-from small components of microelectronics [10,11] to large products [12][13][14][15], artworks [16,17], and engineering structures [14,18,19]. They can also be used to conduct nondestructive testing of materials [20][21][22][23][24][25][26][27], determine their thermal physical characteristics (TPC) [28][29][30][31], and determine the degree of corrosive damage [32]. Thermography is also used successfully for monitoring natural objects in the environment [33], biomedical research and noninvasive diagnosis of various human diseases [9,34,35], and in sports science [36].…”

“…For active nondestructive testing (NDT) and TPC measuring, two measurement methodologies are used: steady and transient [3-9, 23, 27-30, 37]. The old steadystate methods (in particular, guarded hot plate (GHP) and heat-flow meter (HFM) [28]) are still used in practice, though they have several disadvantages because the distribution of heat flux should be sufficiently close to the planned asymptotics without significant uncontrolled heat leakage from the measuring cell. These methods require preparation of samples of specific geometry and a long time to achieve steady state.…”