Fig. 2: Design and characterization of wearable flow sensing devices.
From: A soft thermal sensor for the continuous assessment of flow in vascular access
a FEA simulations of temperature profiles comparing an epidermally mounted thermal (top, previous design) and anemometric (bottom, current design) based sensor, with fixed heater areas of 450 mm2. Simulations and experiments are performed under patent-flow conditions at heater PD of 1 mW/mm2. b FEA simulations of heater sensitivity with respect to heater length and width modulation. c Block diagram of instrumentation, thermal flow sensor, and benchtop vascular flow model in experiments. d IR thermography of heater actuation under no-flow and patent-flow conditions. Selected images show net cooling at 250 s (patent-flow) as compared to 180 s (no-flow). e Time course analysis of heater temperature under no-flow conditions at 0.25, 0.4, 0.55, 1, and 2 mW/mm2 PD (n = 3 technical replicates). f Corresponding steady-state heater ΔT after 400 s as a function of PD. Dotted lines indicate pain receptor activation and clinical dosing limits. Data are presented as mean values ± SEM. Source data are provided as a Source Data file.
