Simulation Research on the Spray Humidifier of the Hydrogen Fuel Cell Testing System

Introduction: This patent focuses on the humidification module in the air supply system of a fuel cell test platform. Based on the principles of droplet evaporation and spray humidification, the structure of the humidifier was designed, and a spray humidifier model meeting the requirements of test conditions was developed. To study the output characteristics of the humidifier, a threedimensional simulation was conducted, and the droplet evaporation process was simulated using the Discrete Phase Model (DPM). Parametric analyses were conducted on the outlet air moisture content by systematically varying the air inlet velocity, humidification water temperature, and air inlet temperature. Methods: The structure of the humidifier was designed based on the principles of droplet evaporation and spray humidification, and a spray humidifier model meeting the test conditions was established. A three-dimensional simulation was performed using the DPM model to analyze the parameters of humid air at the outlet. Experimental tests were conducted to evaluate the humidifier's performance, including droplet atomization efficiency and pressure drop, in order to validate the numerical model. Results: The results show that when the humidification water temperature increases from approximately 50°C to 80°C, the moisture content of the air at the outlet nearly doubles. Meanwhile, an increase in gas flow rate leads to a decline in the humidification performance of the humidifier. Experimental tests confirmed the accuracy of the numerical model, droplet atomization performance, and pressure drop parameters consistent with the simulation results. Discussion: The temperature-dependent moisture enhancement aligns with evaporation kinetics, while reduced performance at higher flow rates suggests shortened droplet contact time. Experimental measurements of atomization and pressure drop verified the numerical model’s accuracy without quantifying deviation ranges. Conclusion: Through structural design and three-dimensional simulation analysis, a spray humidifier model meeting the test conditions was successfully developed. The results demonstrate that humidification water temperature significantly affects performance, while an increase in gas flow rate reduces humidification efficiency. Experimental validation confirmed the accuracy of the numerical model, providing a theoretical basis for the optimized design of the humidifier.