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Fibers are widely used in construction because they have mechanical and thermal properties that improve the properties of structures added to them. This paper addresses the improvements made to the compressed earth block (CEB) when palm fibers and glass are added. This block is made up of soil and cement. The fiber ratio varies between 0% and 0.4%, and a compressive force of 2.5 MPa is applied to the samples. The physical, mechanical, and thermal properties of the CEB are studied according to systematic criteria using a numerical simulation program to find out how heat is transferred inside the samples. Preliminary results showed that the addition of fibers reduces the bulk density value between 1.88% and 11%, increases the compressive strength between 14.28% and 28.85%, decreases the thermal conductivity value between 1.38% and 22.22%, and decreases specific heat observed by 19.34% and 25.77%. These results give a clear view of the changes in the CEB when fibers are added and how to improve some properties.

The investigation of fluid flow and forced convective heat transfer in microchannels with square barriers is the focus of this study. The positioning of obstacles was varied in three cases: at the top wall, bottom wall, and symmetrically distributed on both sides of the microchannel wall. The thermal Lattice Boltzmann Method in conjunction with the Double Distribution Function and Bhatnagar–Gross–Krook approach was used for simulation through computer code in Python. Slip velocity and temperature jump were considered in the boundary conditions for the walls of the microchannel and obstacles. The results demonstrate that the rarefaction effect, placement of barriers, and choice of square obstacles significantly impact fluid flow and heat transfer. An increase in Knudsen numbers (Kn) leads to a decrease in temperature and velocity. The presence of obstructions on both sides of the microchannel walls reduces the fluid's velocity and cools the fluid at the microchannel's exit. The third case, with obstacles on both sides, presents a practical approach for reducing the fluid's temperature at the exit, resulting in the lowest level of skin friction (Cf) and a reduction in the Nusselt number (Nu). The proposed configurations can be utilized to enhance the geometry of microchannels and for cooling purposes in small-scale devices and systems with miniature mechanical and electrical components. The study's findings suggest that the placement of obstacles at the bottom or on both sides, depending on the need for best cooling on both sides or only at the top to reduce material consumption, can achieve low temperature at the exit of a rectangular microchannel. [ABSTRACT FROM AUTHOR]

A reheat Organic Rankine Cycle (ORC) is investigated to recuperate a low-grade heat source using six different organic working fluids (WFs). The results indicate that wet fluids produce more power output compared to dry and isentropic fluids. The reheat pressures of the selected WFs were optimised to maximise the exergy efficiency and minimise the total UA. Reheat pressure ranges of 27–48% and 45–54% of the evaporation pressure were obtained, for ORCs with and without IHE, respectively. A maximum of 49.1% exergetic efficiency is achieved by the addition of IHE: a 13.6% improvement compared to the ORC without IHE. Finally, the results indicate that R236ea and propyne are the best WFs for the ORC with and without IHE, respectively. [ABSTRACT FROM AUTHOR]