Non-Parabolicity Correction for Fifty-Nine Solvents and a Retention Study for Strongly Distorted Flow-Profiles in Thermal Field-Flow Fractionation

Abstract The non-parabolicity correction of the laminar flow profiles was numerically calculated for fifty-nine solvents. The exact flow profiles were simulated based on sophisticated experimental literature data of dynamic viscosity and thermal conductivity and their dependency on the temperature in between cold wall temperatures of –10 °C up to 120 °C and temperature gradients up to ΔT = 120 K. Based on this computation the polynomial coefficients for the calculation of the non-parabolicity parameter ν is tabulated for each solvent. For this calculation a third-degree polynomial velocity profile was applied, which approximates in a good agreement the exact profile for moderately distorted flow profiles. Instead, for strongly distorted flow profiles a more exact solution with keeping ν as only adjustable parameter is proposed. Additionally, an empirically derived solution is presented to calculate the dimensionless retention parameter λ in fair accuracy directly from retention data.