Numerical Simulation and Thermal Optimization of Multi-Layer Insulation (MLI) Systems for Cryogenic Liquid Hydrogen Storage Tanks

                  The present project, titled “Numerical Simulation and Thermal Optimization of Multi-Layer Insulation (MLI) Systems for Cryogenic Liquid Hydrogen Storage Tanks,” focused on studying the thermal behaviour of MLI used to minimize heat transfer into cryogenic liquid hydrogen storage systems. Since liquid hydrogen must be maintained at an extremely low temperature, effective thermal insulation is essential to reduce heat leakage and minimize evaporation or boil-off losses. The study considered the important MLI parameters such as number of insulation layers, layer density, surface emissivity, insulation thickness and vacuum conditions.               The numerical simulation approach provides an effective method for predicting the temperature distribution, heat flux and heat leakage through the insulation system. By varying the important design parameters, the influence of each parameter on the thermal performance of the storage tank can be evaluated. The analysis shows that increasing the number of reflective layers can reduce radiation heat transfer; however, excessive layer density may increase solid conduction. Therefore, an optimum number of layers and suitable layer spacing are required to achieve improved insulation performance.               The study also highlights the importance of maintaining a sufficiently high vacuum around the MLI system. A good vacuum reduces gas conduction between the insulation layers and improves the overall thermal resistance. Similarly, the use of low-emissivity reflective materials helps reduce radiation heat transfer. Proper control of layer density, vacuum pressure and material properties is therefore essential for achieving minimum heat leak and lower liquid hydrogen boil-off.              The optimized MLI system can provide several benefits, including reduced heat leakage, lower hydrogen boil-off rate, improved storage efficiency, reduced refrigeration requirements and better thermal stability. The use of numerical simulation also reduces the need for repeated physical prototypes because different insulation configurations can be evaluated before fabrication. This makes the design and optimization process more economical and time-efficient.                             Overall, MLI is a highly effective insulation technique for cryogenic liquid hydrogen storage applications when it is properly designed, installed and maintained under suitable vacuum conditions. The numerical and optimization approach presented in this project provides a useful foundation for developing efficient cryogenic storage systems. Further experimental validation, advanced material selection, coupled thermal-structural analysis and AI-based optimization can improve the accuracy and practical applicability of the proposed system in future work.

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