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Summary: This work presents and discusses a detailed thermal conductivity assessment of erythritol, xylitol, and their blends: 25 mol% erythritol and 80 mol% erythritol using the transient plane source (TPS) method with a Hot Disk Thermal Constants Analyzer TPS‐2500S. Thereby, the thermal conductivities of xylitol, 25 mol% erythritol, 80 mol% erythritol, and erythritol were here found for respectively in the solid state to be 0.373, 0.394, 0.535, and 0.589 W m−1 K−1 and in the liquid state to be 0.433, 0.402, 0.363, and 0.321 W m−1 K−1. These obtained results are comprehensively and critically analyzed as compared to available literature data on the same materials, in the phase change materials (PCMs) design context. This study clearly indicates that these thermal conductivity data in literature have considerable discrepancies between the literature sources and as compared to the data obtained in the present investigation. Primary reasons for these disparities are identified here as the lack of sufficiently transparent and repeatable data and procedure reporting, and relevant standards in this context. To exemplify the significance of such transparent and repeatable data reporting in thermal conductivity evaluations in the PCM design context, here focused on the TPS method, a comprehensive measurement validation is discussed along various residual plots obtained for varying input parameters (ie, the heating power and time). Clearly, the variations in the input parameters give rise to various thermal conductivity results, where choosing the most coherent result requires a sequence of efforts per material, because there are no universally valid conditions. Transparent and repeatable data and procedure reporting are the key to achieve comparable thermal conductivity results, which are essential for the correct design of thermal energy storage systems using PCMs. [ABSTRACT FROM AUTHOR]

• Properties of two n-alkanes, n-octadecane and n-eicosane are measured and benchmarked with literature values. • A µDSC with large sample mass is used to measure enthalpy and specific heat. • A novel methodology in terms of scanning rate in continuous mode is developed. • Thermal conductivity is measured via Transient Plane Source technique for both solid and liquid phases. • Viscosity of the liquid is measured via a rotational viscometer. Reliable knowledge of phase change materials (PCM) thermo-physical properties is essential to model and design latent thermal energy storage (LTES) systems. This study aims to conduct a methodological measurement of thermo-physical properties, including latent enthalpy, isobaric specific heat, thermal conductivity and dynamic viscosity, of two n-alkanes, n-octadecane and n-eicosane. The enthalpy and isobaric specific heat of the materials are measured via differential scanning calorimetry (DSC) technique, using a µDSC evo7 from Setaram Instrumentation with a sample mass of 628.4 mg. The influence of the scanning rates, varying from 0.5 K/min to 0.025 K/min, in dynamic continuous mode within temperature range of 10–65 °C is investigated. The thermal conductivity and the dynamic viscosity are measured via Hot Disk TPS-2500S instrument and Brookfield rotational viscometer, respectively, up to 70 °C. The thermal analysis results via the µDSC show that the isothermal condition can be approached at a very low scanning rate, however at the cost of a higher noise level. A trade-off is observed for n-octadecane, achieving the lowest deviation of 0.7% in latent heat measurement at 0.05 K/min, as compared to the American Petroleum Table values. For n-eicosane, the lowest deviation of 1.2% is seen at the lowest scanning rate of 0.025 K/min. The thermal conductivity measured values show good agreements with a number of documented literature studies in the solid phase, within deviations of 2%. Larger deviations of 5–16% are found for the measurement in the liquid phase. The viscosity values also show a good agreement with the literature values with maximum deviations of 2.9% and 6.3%, with respect to the values of American Petroleum Tables, for n-octadecane and n-eicosane, respectively. The good agreements achieved in measurements establish the reliable thermo-physical properties contributing to the future simulations and designs. [ABSTRACT FROM AUTHOR]

• The heat transfer characteristics of minichannel-based heat exchangers were studied. • Four prototypes were 3D printed in AlSi10Mg using direct metal laser sintering (DMLS). • 95% of the experimental data were within 10% of the simulation results. • For the channel embedded with the vortex generators, the simulations agreed with the experimental results. • The vortex generator can enhance the convective heat transfer up to three times. • Additive manufacturing can help develop more sophisticated minichannel HXs. Three-dimensional (3D) printing, known as additive manufacturing, provides new opportunities for the design and fabrication of highly efficient industrial components. Given the widespread use of this technique by industries, 3D printing is no longer limited to building prototypes. Instead, small-to-medium scale production units focus on reducing the cost associated with each part. Among the various industrial components that can be developed with this manufacturing technology are heat transfer components such as heat exchangers. To this end, this study investigated the heat transfer characteristics of minichannel-based heat exchangers embedded with longitudinal vortex generators, both experimentally and numerically. Three enhanced prototypes with different vortex generator design parameters and a smooth channel as a reference case were printed with an aluminum alloy (AlSi10Mg) using direct metal laser sintering (DMLS). The rectangular minichannel had a hydraulic diameter of 2.86 mm. Distilled water was used as the test fluid, and the Reynolds number varied from 170 to 1380 (i.e., laminar flow). Prototypes were tested under two different constant heat fluxes of 15 kW m−2 and 30 kW m−2. The experimental results were verified with a commercial simulation tool, Comsol Multiphysics®, using the 3D conjugate heat transfer model. In the case of the smooth channel, the experimental results were also compared with well-known correlations in the field. The results showed that 95% and 79% of the experimental data were within 10% of the numerical simulation results and the values from the existing correlations, respectively. For the channel enhanced with the vortex generators, the numerical predictions agreed well with the experimental results. It was determined that the vortex generators can enhance the convective heat transfer up to three times with the designed parameter. The findings from this research underline the potential of additive manufacturing in the development of more sophisticated minichannel heat exchangers. [ABSTRACT FROM AUTHOR]