Study of porous media usage in the performance of tubular heat exchanger in Continuous hydrothermal flow synthesis method

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Abstract

Continuous hydrothermal flow synthesis processes are implemented for the manufacture of nanoparticle metal oxide. In this processes, metal oxides temperature should be reduced with a convenient rate to avoid forming of larger crystals, which may affect the quality of the products. Using a high-efficiency heat exchanger can help us to gain this purpose. In this study, the first step is to model the heat exchanger in CHFS (Continuous hydrothermal flow synthesis) system numerically, in order to reduce the temperature of the nano-metal oxides. The numerical results are also validated with available experimental data. Then, in the next step, further reduction of product’s temperature is obtained by using a porous media, which eventually leads to an improvement in the products quality. Using the porous media increases the reduction rate of temperature for about 40%, that means 20 oC/s more than the typical heat exchenger and also decreases the required length of the heat exchanger about 35%.

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