Modeling heat transfer to non-Newtonian fluids in a double tube heat exchanger

The temperature distribution of non-Newtonian fluids in laminar flow heated in a double tube heat exchanger was compared to predictions by analytical and numerical methods. Temperature-dependent rheological properties were incorporated into the appropriate models and correlations for heat transfer coefficients were developed in dimensionless from for guar gum and sodium carboxymethyl cellulose (CMC) solutions. The laminar forced convection model was found to best correlate with the data. A good agreement between measured and predicted centerline temperature was obtained using an analytical method. Numerical results led to underprediction of centerline and bulk temperatures.