شبيه‌سازي عددي تاثير ادغام چند روش بهبود انتقال حرارت بر عملكرد يك سيستم ذخيره‌سازي هيدروژن هيدريد‌ فلزي

In this study, the improvement of the process of hydrogen absorption in metal hydride tanks was studied by examining the effect of various methods of increased heat transfer rates an‎d operating parameters. Initially, the performance of the tank with an external cooling sheath, where the peak temperature of the bed was measured to 53 degrees Celsius an‎d the time to reach 90 % of about 182 seconds, was investigated as the base model. Then, by adding the internal cooling Channel, the peak temperature was reduced to 51 degrees Celsius an‎d the adsorption time was reduced to 118 seconds. Next, the addition of thermal fins to the tank structure reduced the absorption time to about 104 seconds. Finally, by using a combination of thermal fins, internal Channel, an‎d expan‎ded natural graphite (ENG) in the bed, the reservoirʹs thermal performance improved significantly, Such that the peak bed temperature decreased to 43°C an‎d the 90% absorption time reached 66. The results showed that the addition of new routes for heat transfer, especially graphite use, resulted in a significant decrease in bed temperature an‎d improved temperature distribution uniformity, resulting in an increase in hydrogen absorption rate. In addition to examining heat transfer improvements, the effect of hydrogen inlet pressure, velocity an‎d cooling water temperature on bed thermal behavior an‎d hydrogen absorption were analyzed. The results showed that the increase in hydrogen inlet pressure from 5 to 30 times increased the final absorption percentage from 87.97 % to 100%; But it resulted in an increase in peak temperature by about 63 degrees Celsius, which needed proper thermal management. Also, increasing cooling water flow rate from 0.05 to 0.2 m/s an‎d lowering temperatures from 25 degrees Celsius to 15 degrees Celsius had a positive effect on reducing bed temperature an‎d accelerating the absorption process. These findings suggest that the optimal combination of cooling methods an‎d precise adjustment of operating parameters can play an important role in improving the performance of metal hydrogen -based hydrogen storage tanks.

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