SU1756724A1 - Swirler for two-phase flow - Google Patents

Abstract

The invention relates to the energy, transportation, oil, gas and chemical industries and can be used to improve the reliability of two-phase transport. The aim of the invention is to minimize hydraulic losses and vibrations of a two-phase channel while stabilizing the flow rate and reducing flow pulsations in the channel by setting at the entrance to the canal of a single-input auger minimum hydraulic resistance. The blades of the whirlwind profile along a smooth curve with one bend and two independent variables, while the optimal length of the variable pitch section of the witness is determined by the relationship: h D-0.082 exp-0085 K 7.5 + + (a - n / 2) 4, where O is the internal di meter swirler (channel); K is the number of blades of the 3– vortex; a- twist angle on the diameter. 1 il.

Description

The invention relates to the energy, transportation, oil, gas and chemical industries and can be used to increase the reliability of two-phase transport.

It is known that during the movement of two-phase flows, in particular, the steam-and-water mixture, the formation of gas and liquid plugs moving along the channel is established — the so-called skull or plug flow mode. The passage of the plugs through local resistances like outlets, section changes, valves, gate valves and others, accompanied by hydraulic shocks and increased vibration of the channel (pipeline). Known methods of protection of the pipeline from vibration can be divided into passive and active.

Passive methods are protection without eliminating the cause, that is, in the presence of a cork mode - the establishment of additional supports, gas-liquid dampers (as of the USSR N 934415, as well as USSR № 9Т4863idr.)

Active methods are characterized in that the effect is directed at the cause, and the flow mode is replaced by a dispersed or ring mode. The implementation of the second method is the spatial orientation of pipelines, the implementation of slopes, the selection and mutual arrangement of local resistances, etc. (and with the USSR No. 28925, 1968, as.S. USSR No. 945584, T980, and S. USSR No. 914862, 1982, and .s. USSR № 934152, 1982).

The prototype of the proposed invention is a pipeline for gas-liquid flows (as. USSR No. 1312298, class F 16

sl about 1 ho Јw

L 52/02, B.I. No. 19, 1987), which includes local resistances and front-mounted multiple-pass screw vortexes with unstressed input and variable pitch lengths. The gas-liquid flow in the bottom-cork regime of flow smoothly without impact enters the scooper. Under the action of acceleration and twisting the plug is destroyed. A dispersion-ring flow regime is established behind the swirler. At the same time, the indicated device does not ensure the achievement of the maximum effect, since the scavenger is not optimal, with a developed separation zone, less twist and large hydraulic losses.

The aim of the invention is to minimize the hydraulic losses and vibrations of the gas-liquid channel while stabilizing the flow rate and reducing the flow pulsations in the gas-liquid channel.

The goal is achieved by profiling the blades of the screw vortex of an unstressed entrance and variable pitch along the length of a section with a smooth curve that has one extremum and two independent variables, while the optimum length of the section of variable pitch is determined by: -.

And 00.082 exp 0 085 to 7.5 + (a - W / 2) 4, (1)

where D is the diameter of the swirler (channel);

K - the number of blades swirl;

and - the twist angle on the diameter.

Formula (1) is the result of a generalization of experiments to determine the optimal length of a Varvigator section of variable pitch. Hydrodynamic study of turbulence and their results are confirmed by the test act, which is attached .. v

Comparative analysis with the prototype shows that the claimed device is characterized by the presence of a variable pitch section shaped along a section with a smooth curve, having one extremum and two independent variables, which gives grounds to conclude that the novelty criterion of the invention is satisfied. Comparison of the proposed solution with other technical solutions shows that the channels, pipelines for two-phase flows are widely known, however, when using a swirler with a variable pitch section with the optimal length calculated from the correlated dependence (1Xpro shows new properties, reduces hydraulic losses, additionally stabilizes the channel, increasing its reliability. This makes it possible to conclude that the technical solution meets the criterion of significant differences.

The proposed device is shown in the drawing.

In the gas-liquid flow channel 1, before the local resistance 2, a multiple feed screw with a minimum hydraulic resistance 3 is established. The intersections of the swirl vanes with the inner surface of the channel form a spatial helical profile 4, the coordinates of which define the profile. On a flat scan of the inner cylindrical surface 5 of channel 4 is represented by a profile line 6, which is a section of a smooth curve with one bend and two independent variables (parabola, ellipse, Nikhohomed conchoid, Pascal cochlea; Cassini lines, etc.). Independent variables are determined by the optimal length, the diameter of the channel D, the number of turns n, performed by one spatula, p- ...... X-D

iga

(2)

The proposed device works as follows.

The flow in the bottom flow mode enters the smelter. On the evacuator with minimal hydraulic losses, the flow is rebuilt into a dispersion-ring mode and its passage through the local resistance 2 is not accompanied

water hammer and vibration.

An example of a specific implementation of the device is a pipeline containing copper, brass, or stainless steel, three-blade, with a length of H 0.48 O and a twist angle of 70 ° at the exit. The blades can be fixed on the inner surface of the channel, as well as on the central rod with fairings by welding or soldering. Formula b and b ay a breeze squeezer containing a multiple-running auger with an unstressed entrance and variable pitch along the length, installed in the cylindrical channel in front of the local hydraulic resistance, so that minimizing hydraulic losses and channel vibration while stabilizing the flow rate and reducing flow pulsations, the auger edges at the intersection with the channel surface form smooth curves with

Claims (1)

Claim A swirl for a two-phase flow containing a multi-auger screw with no comparison of the proposed solution with other shock input and a variable length step installed in a cylindrical channel in front of a local hydraulic joint, in order to minimize hydraulic losses and channel vibration while stabilizing flow and reducing pulsation of the flow, the screw edges in at the intersection with the channel surface, smooth curves form with resistance, with the fact that, in order to minimize hydraulic by one bend, and the screw length h is chosen to be clear. h = D »0.082 exp ^{45.085 k} (7.5 + (a-π / 2) ⁴ ], where D is the internal diameter of the channel, K is the number of entries, and a is the angle at the exit of the screw.