Dynamic Modeling and Nyquist Stability Analysis of a Non-Interacting Two-Tank Series Thermal System
DOI:
https://doi.org/10.31004/jestm.v6i2.431Keywords:
Two-tank series system, Nyquist plot, Dynamic modeling, Process control, System stabilityAbstract
Series tank systems are vital in chemical industries but susceptible to mass and thermal disturbances, making stability analysis essential. This study models the level and temperature dynamics of a non-interacting two-tank system equipped with a heater in Tank-01, analyzing its stability via Nyquist plots. The methodology involves laboratory step-response experiments validated against mathematical models derived using Laplace Transforms and Explicit Euler methods. Results demonstrate the model closely matches experimental data; Tank-01 exhibits first-order characteristics, while Tank-02 functions as a second-order system. The physical system successfully handled +52% and -35% step disturbances within liquid height limits of 3–24 cm and feed flow rates of 40.33–136.5 cm³/s. Furthermore, Nyquist analysis confirms the open-loop thermal process is inherently stable across all tested capacities. Maximum level and thermal process gains were 0.3787 and 0.0062, respectively. Ultimately, this study confirms the non-interacting two-tank system possesses stable, self-regulating characteristics against load disturbances within operational limits.
References
Akkoç, M. T. (2025). Fuzzy-PID Controller for Coupled Tank Systems. Journal of Intelligent Decision Making and Granular Computing, 1(1), 256–265.
Ball, R. (1999). The origins and limits of thermal steady–state multiplicity in the continuous stirred tank reactor. Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 455(1981), 141–161.
Ballesteros-Moncada, H., Herrera-López, E. J., & Anzurez-Marín, J. (2015). Fuzzy model-based observers for fault detection in CSTR. ISA Transactions, 59, 325–333.
Borisov, M., Dimitrova, N., & Simeonov, I. (2020). Mathematical Modeling and Stability Analysis of a Two-Phase Biosystem. Processes, 8, 791. https://doi.org/10.3390/pr8070791
Chen, S., Cao, X., Liu, Y., Wang, Z., & Zhang, J. (2024). Multi-frequency oscillation characteristics and stability of the pumped storage power station based on a theoretical analytical method. Journal of Energy Storage, 102, 114016. https://doi.org/https://doi.org/10.1016/j.est.2024.114016
Hermawan, Y. D., Reningtyas, R., Kholisoh, S. D., & Setyoningrum, T. M. (2016). Design of Level Control in A 10 L Pure Capacitive Tank: Stability Analysis and Dynamic Simulation. International Journal of Science and Engineering, 10(1), 10–16.
Hermawan, Y. D., Yogi Suksmono, E. S., Cicilia, E., & Aisyiah, D. S. (2010). Dinamika Suhu pada Sistem Tangki-Seri-Tak-Berinteraksi dengan Arus Recycle. Prosiding Seminar Nasional Teknik Kimia “Kejuangan” ISSN, 1693, 4393.
Kim, V. A., & Parovik, R. I. (2022). Application of the explicit Euler method for numerical analysis of a nonlinear fractional oscillation equation. Fractal and Fractional, 6(5), 274.
Naik, R. B. B., & Kanagalakshmi, S. (2020). Mathematical modelling and controller design for interacting hybrid two tank system (IHTTS). 2020 Fourth International Conference on Inventive Systems and Control (ICISC), 297–303.
Nise, N. S. (2025). Control Systems Engineering. John Wiley & Sons, Limited. https://books.google.co.id/books?id=nFIrEQAAQBAJ
Ogata, K. (2020). Modern control engineering.
Seborg, D. E., Edgar, T. F., Mellichamp, D. A., & Doyle, F. J. (2016). Process Dynamics and Control. Wiley. https://books.google.co.id/books?id=ZZVFEAAAQBAJ
Suryatini, F., Salam, A., & Natasha, S. (2024). Water Level Control in Coupled Tank System with PLC and IoT-Based PID Method. The Indonesian Journal of Computer Science, 13(4).
Tunjung, D., Prajitno, P., & Handoko, D. (2021). Temperature and water level control system in water thermal mixing process using adaptive fuzzy PID controller. Journal of Physics: Conference Series, 1816(1), 12032.
Wang, Q., Chen, S., Chen, F., Zhang, J., Chen, L., Li, J., & Dou, Z. (2024). A dynamic assessment method for risk evolution in chemical processes based on MFM-HAZOP-FDBN. Chemical Engineering Research and Design, 204, 471–486. https://doi.org/https://doi.org/10.1016/j.cherd.2024.02.049
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