Performance of a novel-type of heat flue in a coke oven based on high-temperature and low-oxygen diffusion combustion technology

A new type of two-supply, one-return, triple pipe-structured heat loss model based on a low temperature district heating system

Cooling performance of a portable box integrating with phase change material (PCM)-based cold thermal energy storage (TES) modules was studied and reported in this paper. The effects of locations of the PCM modules, melting point of the PCM, and insulation materials on the cooling duration of the box were numerically investigated with an experimentally validated model. Five configurations of PCM modules inside the box were examined: Case 1 - 100 % of the PCM located at the top; Case 2 - 20 % at the top and 20 % on each of side walls; Case 3 - 25 % on each of the side walls; Case 4 - 20 % on each of the side walls and 20 % at the bottom; and Case 5 - 100 % at the bottom. Five different PCMs with melting points at 2 °C, 3 °C, 4 °C, 5 °C and 8 °C were considered. A comparison was made between two different insulation materials (polyurethane, vacuum insulated panels) on the cooling performance. It was found that the configuration of PCM modules, the PCM melting point, and the type of insulation material all affected the cooling durations. The configuration of PCM with 20 % located at the top and 20 % on each of the side walls, with the melting point at 2 °C and the vacuum insulated panel (VIP) gave the longest duration time. The maximum cooling time was up to 46.5 h with the maximum discharging efficiency at 90.7 % and the highest discharging depth at 99.4 %, offering a great potnetial for cold chain applications.

Cooling performance of a thermal energy storage-based portable box for cold chain applications

Hybrid or mono nanofluids for convective heat transfer applications. A critical review of experimental research

Nanofluids have been widely used as working fluids in thermal systems on account of their enhanced aptitudes on heat transfer. In this paper, an aqueous hybrid nanofluid suspension including Fe and CuO nanoparticles (50:50) was prepared at 2 % mass concentration and utilized as working fluid inside a plain heat pipe under miscellaneous working conditions implemented on both evaporator and condenser regions. As a non-ionic surfactant, Triton X-100 was doped into the hybrid suspension at 0.2 % mass concentration for providing stability and extending the hanging time of the nanoparticles. So as to determine the influence of hybrid nanoparticle inclusion in the base fluid on thermal characteristics, a set of experiments for both distilled water and hybrid nanofluid were executed by considering the same operating conditions. Temperature distributions were measured and recorded. These records were used while calculating the heat pipe’s thermal efficiency and thermal resistance, and improvement rates in both were determined. Experimental findings illustrated that hybrid nanofluid utilization decreased the overall wall temperatures and advanced the thermal efficiency of the plain heat pipe up to 72.63 %. Similarly, the heat pipe’s thermal resistance values were able to be declined up to 0.0070 K·W−1 by hybrid nanofluid usage in lieu of distilled water, which also corresponded to a maximum increment rate of 16.91 %.

Lihong Qiao

Papers

A comparative investigation on the effect of different nanofluids on the thermal performance of two-phase closed thermosyphon