Analytical design and computational fluid dynamics analysis for optimizing fixed ventilation systems for power transformer: Numerical study and experimental validation

Abstract

Despite the recognized fact that power transformers (PT) are highly efficient technology, part of their electrical energy is counted as heat losses. Therefore, the cooling system is a critical factor in the life span and performance of the PTs, and hence the adopted thermal energy design can be strongly effective. This study revolves around the innovative development of a novel generation of fixed ventilation fans for PTs, achieved through Computational Fluid Dynamics (CFD) simulations and practical experiments. The proposed CFD model was developed adopting ANSYS FLUENT 19.2. The proposed CFD model was verified by comparing the numerical and experimental results of the cooling air temperature and velocity. A standard k-ε model was used to simulate the airflow of the investigated cooling system numerically. A thermal analysis of a four-sided power transformer was performed, and an analysis of the optimum position to install the cooling fan on the radiator was presented. The most effective number of used fans was also determined. The main results showed that two fans were found to be the best performance among the tested candidate alternatives. The two cooling fans’ size, material, and cover shape were also studied and added to the proposed model. Besides, the utilization of a thermoelectric generator was considered in this study in order to recycle some of the lost heat into output power. An experimental prototype mimicking the actual cooling system for the power transformer was designed and fabricated. Results showed that the selected material has achieved a high Calculated Factor of Safety (FoS) equal to 237, indicating that the utilization of the designed parts is of high safety.

Keywords:

• Experimental validation
• numerical study
• power transformers
• thermal CFD analysis
• thermoelectric generator

Authors’ contributions

All authors contributed to the study conception and design. Nizar F.O. Al-Muhsen, Firas Basim Ismail, and Thabit Sultan Mohammed: data curation, conceptualization, supervision, methodology, writing- original draft preparation. Hussein A. Kazem, Ammar Al-Bazi: investigation and writing- reviewing and editing; Navin Raaj Pillai Mahathavan: investigation, writing- reviewing and editing, methodology.

Disclosure statement

We the authors declare no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

Data availability statement

The research data is available upon request. To request the data, contact the first author of the article.