Horizontal capillaries

Crystal growth can be conveniently viewed by holding the capillary horizontally under a microscope. The advantages of a dialysis method are, of course, that the capillary can be placed easily into reservoirs with different solutions. Figure kindly supplied by J. Drenth, University of Groningen and reproduced with permission. 

Since the neighbour slugs oscillate in phase opposition under shock load, pressure oscillations in the liquid plug should be restrained. Really the wave here turns out to be monotonous and its amplitude coincides practically with pressixre in the incident wave (Fig. 3). The applicability of Bq. (1) to the wave analysis is confirmed by experimental results ["l0. Fig.4 shows the comparison of these experiments conducted in a capillary horizontal tube ( 5 mm diam.) with air-water medium of slug structure, with the data of calculation by (1). 

Hold the tube horizontally and quickly seal this end in a micro-burner. Attach the tube (with the open end upwards) to a thermometer in the melting-point apparatus (Fig. i(c), p. 3) so that the trapped bubble of air in the capillary tube is below the surface of the bath-liquid. Now heat the bath, and take as the b.p. of the liquid that temperature at which the upper level of the bubble reaches the level of the surface of the batn liquid. 

Figure 3.10 is a plot of potential against distance from the wall for a liquid in a capillary of sufficient width for its middle A to be outside the range of forces from the wall. Since the capillary condensate is in equilibrium with the vapour, its chemical potential (=p represented by the horizontal line GF, will be lower than that of the free liquid the difference in chemical potential of the condensate at A, represented by the vertical distance AF, is brought about entirely by the pressure drop, Ap = 2y/r , across the meniscus (cf. Equation (3.6)) but at some point B. say, nearer the wall, the chemical potential receives a contribution represented by the line BC, from the adsorption potential. Consequently, the reduction Ap in pressure across the meniscus must be less at B than at A, so that again... 

Serizawa et al. (2002) studied experimentally, through visualization, the two-phase flow patterns in air-water two-phase flows in round tubes. The test section for air-water experiments consisted of a transparent silica or quartz capillary tube with circular cross-section positioned horizontally. The two-phase flow was realized through a mixer with different designs, as shown in Figs. 5.4 and 5.5. The air was injected into the mixer co-axially while water was introduced peripherally. 

Kariyasaki A, Fukano T, Ousaka A, Kagawa M (1991) Characteristics of time-varying void fraction in isothermal air-water co-current flow in horizontal capillary tube Trans JSME 57(544) 4036-4043... 

Lezzi AM, Niro A, Beretta GP (1994) Experimental data on CHF for forced convection water boiling in long horizontal capillary tubes. In Hewitt GF (ed) Heat Transfer 1994 Proceedings of the 10th International Heat Transfer Conference, vol 7, Institution of Chemical Engineers, Rugby, pp 491 96... 

To describe the flow in a horizontal heated capillary we use the mass, momentum and energy balance equations. At moderate velocity, the effects due to compressibility of liquid and vapor, as well as energy dissipation in gaseous and liquid phases are negligible. Assuming that thermal conductivity and viscosity of the vapor and the liquid are independent of temperature and pressure, we arrive at the following system of equations ... 

In order to simplify the analysis, we will consider the capillary flow of a hquid L in a horizontal small tube (diameter much smaller than the capillary length), in order to avoid complications due to gravity effects (Fig. 14). 

FIG. 15 Flow rate of TCP in a horizontal capillary tube (r = 0.1 mm) in the case of purely viscous braking (f/i, rigid material) and in the case of viscoelastic braking (U2, soft rubber). 

FIGURE 6.4 Horizontal ES chamber 1 — mobile phase reservoir, 2 — capillary siphon, 3 — small cover plate with distributor plate, 4 — base plate, 5 — adsorbent layer, 6 — carrier plate, 7 — main cover plate, 8 — additional cover plate used to close the chamber. (From Soczewinski, E., Planar Chromatography, Vol. 1, Kaiser, R.E., Ed., Huethig, Heidelberg, 1986, pp. 79-117. With permission.)... 

Fig. 2.11 (a) Dissection of VNC — Mouse Lemur (Microcebus murinus). Cl-C3 = Para-septal cartilage bars LV = ventral vein NC = arterioles/capillary network SV = dorsal vein and VNw = ventral wall (from Schilling, 1970). Vomeronasal complex in murine Rodents. Comparison of LS with TS in Rat (b) LS (horizontal). VV = vascular sinus arrow = venous diverticulum = VN lumen and NE = neuroepithelium (from Larriva-Sahd, 1994). (c) TS (coronal). G = glands RFE = non-sensory epithelium (from Mendoza, 1993). 

A Newtonian fluid with SG = 0.8 is forced through a capillary tube at a rate of 5 cm3/min. The tube has a downward slope of 30° to the horizontal, and the pressure drop is measured between two taps located 40 cm apart on the tube using a mercury manometer, which reads 3 cm. When water is forced through the tube at a rate of 10 cm3/min, the manometer reading is 2 cm. 

FIGURE 6.3 Sandbox model showing LNAPL overlying capillary fringe, and apparent vs. actual LNAPL thickness. Saturated conditions (water table) are represented by the straight horizontal line. 

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