Borosilicate nozzles manufactured by reproducible fire shaping

A new fire shaping approach to produce highly axisymmetric and reproducible nozzles

“…Table 2 shows the shaping conditions for each series and the average geometrical results for the corresponding nozzles. The diameter reproducibility is good, similar to that obtained with the SVF approach, and much higher than the corresponding for TVF (Muñoz-Sánchez and Cabezas, 2018). The nozzle symmetry is also very good, with a misalignment angle α of the neck and capillary axes typically below 1°and a offset distance e of both axes at the neck section below 20 μm.…”

“…At the visible limit of the blue cone, which corresponds approximately to z = 30 mm, the temperature drop at the center is very limited. When we move away from the burner, there is a small increase of the maximum temperature for the profile, remaining in all cases below the corresponding values measured at the side of the vertical flame (Muñoz-Sánchez and Cabezas, 2018). The change in the slope of the temperature profile is more significant.…”

“…The heating temperature and the temperature profile affect, not only the heating time to produce a particular diameter nozzle, but also the nozzle shape. Our experiments with the previous fire shaping approaches showed that a smoother temperature variation in the heating region, such as in TVF, results in longer nozzles (Muñoz-Sánchez and Cabezas, 2018). As the flame used in the TLF approach is different, the temperature profile is also different.…”

“…The experimental setup is very similar to, and the procedure is exactly the same as, the corresponding for the previous approaches (Muñoz-Sánchez and Cabezas, 2018). The former (Fig.…”

“…However, the SVF approach seems to produce the shortest. Recently, we built an experimental setup for these two approaches and carried on a systematic study to evaluate their performance (Muñoz-Sánchez and Cabezas, 2018). We focused on the nozzle diameter and shape reproducibilities, and on its symmetry.…”