Work

Integrated RSM-evolutionary framework for multi-objective thermo-hydraulic optimization of solar-assisted doubly coiled tube heat exchanger for sustainable thermal systems

Year: 2026

Type: article

Abstract: In this study, the thermo-hydraulic performance of a doubly coiled tube heat exchanger (DCTHE) is investigated corresponding to four input parameters, that is, helical tube diameter, hot-water inlet temperature, hot-water flow rate, and air velocity. The heat transfer effectiveness, JF factor, and depletion number are determined as thermo-hydraulic and sustainability measures for the proposed DCTHE for efficient air-heating applications. 27 experimental runs are conducted to assess the performance of the DCTHE using Response Surface Methodology (RSM) models, confirming the experimental design produced by the Box-Behnken design. The developed RSM models are validated with real data, showing excellent agreement, with R² values of about 0.99 for effectiveness, 0.97 for the JF factor, and 0.99 for the depletion number. Subsequently, four evolutionary algorithm techniques are used and compared using the RSM model data to predict the optimized performance of the DCTHE. The Sequential Least Squares Programming (SLSQP) approach produced a quick single-objective optimum, while Differential Evolution (DE) and a modified Genetic Algorithm (GA) produced a similar solution with an efficacy of around 0.49 and substantial pressure drop and depletion. The Non-Dominated Sorting Genetic Algorithm II (NSGA-II) with a balanced trade-off solution provides optimal performance for DCTHE, with a maximum effectiveness of 0.686, a JF factor of 0.021, and a minimum depletion number of 0.332. The suggested doubly coil tube heat exchanger exhibits superior thermo-hydraulic performance and exergy utilization under similar operating conditions, with 13.3% higher effectiveness, 8.49% higher JF factor, and 11.98% lower depletion number, compared to the single helical coil configuration.

Source: Results in Engineering

DOI: 10.1016/j.rineng.2026.112709

Authors: Pradeep Kumar Nayak, Taraprasad Mohapatra, Sudhansu S. Mishra, Mukesh Bathre, Pankaj Shrivastava, Velaphi Msomi

Institutions: C.V. Raman Global University, Government College of Engineering, Keonjhar, University of South Africa

Language: English

Topic: Heat Transfer and Optimization

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Affordable and clean energy, Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $1,940