Statistical method to calculate local interfacial variables in two-phase bubbly flows using intrusive crossing probes

Local parameters of air–water two-phase flow at a vertical T-junction

“…The existing literature for needle probe sensors (Kataoka et al, 1986;Kataoka and Serizawa, 1990;Revankar and Ishii, 1992;Kalkach-Navarro et al, 1993;Cartellier, 1999;Dias et al, 2000;Fu, 2001;Wu et al, 2001;Kim et al, 2001;Euh et al, 2001;Shen et al, 2005;Pradhan et al, 2013) is employed to measure the local two-phase flow parameters in the present work. The four-sensor conductivity probe design used in the present experiments is based in the previous work of (Kim et al, 2001) and consisted of 4 enamelled copper wires (0.2 mm outer diameter).…”

The phase distribution of upward co-current bubbly flows in a vertical square channel

“…As the channel had square cross-section, the mean bubble diameter was taken, sampling a number of bubbles from various frozen images of the channel lateral view, by comparison with the channel side. A fully description of the conductive probe used to measure the void fraction, including the electronics and the data acquisition can be found in Dias et al (2000) and Matos et al (1999).…”

“…Details of the data processing technique can be found in Dias et al (2000). It is worthwhile to mention that using the above-described procedure the number of digitally acquired points used to calculate the void fraction distribution over the channel section amounted to 4.2 x 10 7 .…”

Characteristic lengths and maximum entropy estimation from probe signals in the ellipsoidal bubble regime

“…Dias et al (2000) proposed a non-aprioristic statistical method for spherical bubbles to describe the influence of the angle of attack on the apparent (measured) and actual (real) distribution and they applied the model to their experiments, carried out in an air/water bubbly flow regime. Furthermore, Clark and Turton (1988) and Turton and Clark (1989) proposed a non-parametric numerical method, which was shown to be numerically unstable for small sampling records.…”

“…Although it is not the purpose of the present paper to discuss the measurement errors in chord-length determination from probe readings due to bubble probe interaction (Julia et al, 2005), uncertainly in bubble orientation and shape, etc., it is important to mention that significant errors in PDFs estimation arise in practice since the actual chord obtained from an ideal probe does not coincide with the measured chord, especially in cases of small chords (Dias et al, 2000) and distorted bubbles (Chaumat et al, 2005).…”