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The logarithmic mean temperature difference of a plate heat exchanger refers to the average of the temperature differences between the fluids on both sides of the plates, and it is an important indicator for evaluating the heat transfer performance of plate heat exchangers. Next, the editor will introduce to you the methods for increasing the logarithmic mean temperature difference of plate heat exchangers: 1. The common flow patterns in heat exchangers are counterflow, co-flow, and mixed flow. For heat exchangers with various flow patterns, under the same inlet and outlet temperature conditions, the logarithmic mean temperature difference is larger for counterflow, smaller for co-flow, and intermediate for mixed flow. Therefore, when designing and selecting heat exchangers, a counterflow or mixed flow pattern close to counterflow should be adopted as much as possible. 2. Increase the temperature of the hot-side fluid or decrease the temperature of the cold-side fluid as much as possible. Increase the temperature difference between the cold and hot fluids to thereby increase the average temperature difference. 3. For plate heat exchangers with a single-flow arrangement, to facilitate maintenance, the fluid inlet and outlet pipes should be located as close as possible on the side of the fixed end plate of the heat exchanger. The arrangement of multiple processes has a significant impact on the average temperature difference. The greater the temperature difference in the medium, the stronger the natural convection of the fluid, and the greater the impact of the resulting stagnation zone. Therefore, the inlet and outlet positions of the medium should be arranged such that hot fluids enter from above and exit from below, while cold fluids enter from below and exit from above, in order to reduce the impact of the residence time zone and improve heat transfer efficiency.