Figure 7: Study of thermal processes in a reactive hyperaemia test.

(a) Line graphs of temperatures along the horizontal dashed red line in Fig. 6b, at various times. (b) Line graphs of temperatures along the vertical dashed red line in Fig. 6b, at various times. (c) Rate of blood flow through the ulnar artery determined by comparison of thermal models with experimental results. The key parameters include: the occlusion time (t_occ)=160 s; time-to-peak-flow (t_dw)=15 s; the baseline flow rate (ω₀)=30 ml min⁻¹; the occluded flow rate (ω_s)=1.5 ml min⁻¹; and the peak flow rate (ω_max)=90 ml min⁻¹. (d) Measured temperature rise at the surface of the skin above the ulnar artery during the occlusion along with results from finite element analyses (FEA) using the blood flow rate in frame c. The eight sub-frames correspond to the temperature histories of different points at the horizontal dashed red line in Fig. 6b.