No abstract

No abstract

This study investigates the single-phase heat transfer, pressure drop, and temperature distribution of water in an industrial plate and shell heat exchanger (PSHE) under high-temperature conditions. In this experiment, the hot fluid flows downward on the plate side, while the cold fluid flows upward on the shell side. In the single-phase heat transfer experiment on water, the Nu is in the range of 7.85–15.2 with a Re from 1200 to 3200, which is substantially lower than that on the plate heat exchanger (PHE) studied previously. The decrease in the Nu is attributed to the reduced cross-sectional heat transfer area from the flow imbalance in the PSHE. As the Re increases, the pressure drop on the plate side increases more rapidly than that on the shell side because of the difference in the port pressure drop, flow direction, and flow position on the plate. When the Re is 2620, the pressure drops on the plate and shell sides are 52.5 kPa and 25.5 kPa, respectively, a difference of 51.4%. The temperature deviation on the circular plate increases as the Re decreases, especially between the edge and bottom of the plate because of uneven flow distribution on the plate.

Solar air thermal collectors are one of the technologies used to improve the efficiency of fresh air heating system in building spaces. Solar air collectors have the advantage of preventing freezing and overheating problems when compared with solar water collectors. However, thus far, there have been no harmonized thermal performance test facilities or round robin tests (RRT) based on the international standard ISO 9806 in Korea. In this study, an ISO 9806 thermal performance test facility was introduced and designed. In addition, an RRT was conducted based on ISO 9806 and compared to RRT sample Exova performance test results to verify the consistency of the thermal performance. The thermal efficiency ranged 36.06% ~ 72.02% depending on a change flow rate change of 36.6 ~ 182.9 m 3 /(hr•m 2 ), respectively. The RRT was successfully conducted to compare the results of the Exova thermal performance test. A comparison between the Exova and KIER tests showed a relative error of 5.51% and 6.42% for ambient wind velocities of 1.0 and 1.8 m/s, respectively.