Abstract

The increasing demand for thermal energy in residential and industrial sectors highlights the need for reliable and efficient thermal energy storage solutions. Phase-change material-based thermal energy storage systems offer high-density heat retention, but laboratory-scale setups often rely on expensive hardware, limiting customization for iterative experimental testing and validation. This work presents the design, fabrication, and validation of a cost-efficient, customizable, open-source phase-change material-based thermal energy storage unit based on parametric modeling and fused filament fabrication 3D printing. After developing the parametric 3D model, a customized module was fabricated to validate the approach through thermal, numerical, and economic analyses. The parametric model enables rapid iterative customization using low-cost 3D printers, commercially available materials, and off-the-shelf components. Experimental validation demonstrated its reliability under hydrostatic leakage tests and repeated thermal cycles, using circular finned tubes as heat transfer elements and n-octadecane as the storage material. Increasing the heat transfer fluid flow rate from 0.0033 kg·s⁻¹ to 0.0105 kg·s⁻¹ enhanced heat transfer performance and reduced melting and solidification times by approximately 36% and 39%, whereas thermal imaging confirmed uniform temperature propagation within the cavity. A calibrated numerical model reproduced melting and solidification behavior with 13% and 14% prediction error. The complete prototype costs 644.88 USD, with 3D-printed parts below 4% of the total and a cost per cycle of 6.45 USD over 100 cycles. The results demonstrate an accessible approach to experimental research on phase-change material-based thermal energy storage, addressing the need for affordable, customizable setups for sustainable and renewable energy applications. 1

Keywords

Additive manufacturing // Thermal energy storage (TES) // Fused Filament Fabrication (FFF) // Phase Change Material (PCM) // Open source hardware // Heat transfer // Thermal battery

Resources and links

• 📝 Full text (preprint version) 2
• 🛠️ OSF Repository (3D models and dataset) 3