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@article{188187,
        author = {Athappan V and Vaishnavi S and Aparna Renganayakhi N and Aatheeruban K B},
        title = {Nonlinear Dynamic Behaviour Analysis of Spherical Tank Level System},
        journal = {International Journal of Innovative Research in Technology},
        year = {2025},
        volume = {12},
        number = {7},
        pages = {963-968},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=188187},
        abstract = {Spherical tanks are widely used in industrial processes due to their structural strength and ability to withstand high pressure. However, their unique geometry introduces strong nonlinearities into the level–volume relationship, making the level control problem significantly more complex compared to linear tank structures. The objective of this study is to investigate and analyse the nonlinear dynamic behaviour of a spherical tank level system through experimental validation and mathematical characterization. An open-loop analysis was performed using a real-time setup consisting of a differential pressure transmitter, DAQ module, pump, and MATLAB/Simulink interface. The dynamic response was recorded for various inflow conditions to identify key parameters such as steady-state gain, time constant, and dynamic sensitivity across different level ranges. A conventional closed-loop PID controller was then implemented to observe its behaviour under nonlinear conditions. The experimental results show that the spherical tank has different dynamics depending on the region: faster level variation occurs in the bottom and top regions, and slower variation occurs in the mid-level region. This outcome points to the shortcoming of fixed-gain linear controllers in view of the necessity of advanced nonlinear or adaptive control methods for improved performance. In this respect, the comprehensive analysis presented herein constitutes a sound basis for future research work concerning the development of intelligent control strategies.},
        keywords = {Spherical tank, nonlinear system, PID control, dynamic modelling, liquid level system, real-time analysis},
        month = {December},
        }