Experimental investigation of fluid-dependent thermal performance in helical-grooved tube spiral wound heat exchangers: Optimization strategies for high-viscosity applications

Abstract This study conducts a systematic experimental comparison of spiral wound heat exchanger (SWHE) prototypes featuring helical-grooved tubes (HT) versus plain tubes (PT), evaluating thermal-hydraulic performance through three critical metrics: heat transfer coefficient ( K ), pressure drop (Δ P ), and performance evaluation criterion (PEC). Key findings reveal a decisive fluid-property dependence: for water flow in tubes, HT-SWHE exhibits 8.5~26.4% lower PEC than PT-SWHE due to dominant friction penalties outweighing marginal heat transfer gains; for oil flow in tubes, HT-SWHE achieves 15.8~32.3% higher PEC than PT-SWHE, leveraging groove-induced turbulence to enhance heat transfer with moderate pressure drop increases; for shell-side water flow, PEC differences between HT/PT configurations remain negligible (