The thermal diffusivity of evacuated and liquid-saturated borosilicate glass sieves (frits) of porosities between 20 % and 48 % is presented as measured at room temperature. The saturants cover a range in thermal diffusivity from 0.091 mm²·s⁻¹ to 0.143 mm²·s⁻¹. The runs were carried out using a transient hot bridge (THB) measuring instrument of an expanded uncertainty of 5 % to 10 %. The experimental results are successfully fitted to a novel transient parallel-serial (TPSC) conduction model for the time-dependent composite heat transfer in porous media. The TPSC-model is an extension of the steady-state parallel-serial conduction (PSC) model to predict the thermal conductivity. The TPSC model confirms the so-called thermal porosity of the frits under test, a term that has been introduced in a former report on the thermal conductivity of the matrices (Hammerschmidt and Abid, Int J Thermophys 42:40, 2021). The experimental findings on the conductive transport of heat by glass sieves and their accurate mathematical description in the framework of the PSC and TPSC models might effectively support improving the thermal management of electronic devices and lithium-ion batteries.

抽真空和液体饱和的硼硅酸盐玻璃筛（玻璃料）的孔隙率在室温下测量为20％至48％。饱和剂的热扩散率范围为0.091 mm ² ·s ^-1至0.143 mm ² ·s ^-1。运行使用瞬态热桥（THB）测量仪器进行，不确定性范围为5％到10％。实验结果成功地拟合了一种新颖的瞬态并行串行（TPSC）传导模型，用于多孔介质中随时间变化的复合材料传热。TPSC模型是稳态并行串行传导（PSC）模型的扩展，用于预测导热系数。TPSC模型确定了被测玻璃料的所谓热孔隙率，该术语已在先前有关基质热导率的报告中引入（Hammerschmidt和Abid，Int J Thermophys 42：40，2021）。