Numerical and Experimental Investigation of Flow, Heat Transfer, and Structural Behavior of EPDM- and PA12-Based Automotive Cooling Hoses

Abstract

In this study, the flow, heat transfer, structural integrity, and dynamic behavior of EPDM- and PA12-based automotive cooling hoses were comparatively investigated using a combined numerical and experimental approach. Three-dimensional CFD analyses were performed to evaluate internal velocity fields, temperature distributions, and pressure losses under identical operating conditions. Structural and modal analyses based on the finite element method were conducted to assess deformation levels, stress distributions, and natural frequencies. The numerical results were validated through experimental burst pressure tests. The results demonstrate that PA12 hoses exhibit significantly lower deformation, higher natural frequencies, and superior pressure resistance compared to EPDM hoses. Experimentally, EPDM hoses failed at approximately 16.2 bar, whereas PA12 hoses withstood pressures exceeding 59 bar, corresponding to about a +264% improvement in burst pressure capacity. For a representative geometry, the maximum deformation was reduced from approximately 8.2 mm (EPDM) to 4.83 mm (PA12) under identical loading conditions. While EPDM provides higher flexibility and vibration damping, PA12 demonstrates enhanced dimensional stability and structural robustness under high temperature and pressure conditions. The findings highlight the critical role of material selection in achieving safe, durable, and efficient automotive cooling line designs.

Keywords

• Automotive cooling systems
• EPDM
• PA12
• computational fluid dynamics (CFD)
• heat transfer
• structural analysis
• burst test
• modal analysis

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