JPH05337352A - Apparatus for mixing liquids in nongraviation environment - Google Patents

Abstract

PURPOSE:To enhance mixing capacity in an apparatus for mixing liquids in a nongravitation environment. CONSTITUTION:A fluid 2 flowing in a longitudinal direction and a fluid 4 flowing in a lateral direction are mixed at a T-shape crossing point 5 to form a passage flowing in the lateral direction and the inside diameter of a longitudinal passage 1 is finely throttled toward the crossing point 5 and the crossing axis of the longitudinal passage 1 is eccentrically formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid mixing device in a microgravity environment such as space. Recently, the space environment has been used as a place for growing various crystals and as a place for manufacturing new materials.

However, in the space environment, unlike the earth, there is a physical phenomenon due to microgravity. Therefore, in conducting research and development and manufacturing of various materials, it is important to fully understand the characteristics of the space environment.

[0003]

2. Description of the Related Art A few ml in a microgravity environment such as space
Often there is a need to mix liquids of moderate or less volume homogeneously.

In general, when the liquid to be handled is volatile or minute, it is customary to rely on trained personnel for the operation, but when it is performed in space, it is difficult to launch a satellite and the cost is high. It is necessary to automate the operation because it becomes tedious.

[0005] For example, proteins such as enzymes and antibodies have been studied in the form of biosensors because of their high molecular discriminating power. For that purpose, it is necessary to obtain single crystals containing no impurities in perfect form. Is required, and it is expected that crystallization will be performed in outer space as a method.

However, even in this case, it is difficult for a skilled experimenter to carry out, and it is necessary to use an automated device. In order to crystallize a protein, it is necessary to mix a small volume of a solution containing a valuable protein sample with a solution of a crystallization agent.As a crystallization agent, an inorganic salt with a high ionic strength such as ammonium sulfate or chloride is used. Cesium, sodium chloride and organic solvents such as polyethylene glycol, acetone, ethyl alcohol are used.

However, these solutions often have a density different from that of the protein solution, so that it is difficult to perform stirring and mixing. The inventors examined the function and structure of the agitation mixer in the microgravity environment caused by the ballistic flight of the aircraft. As a result, under the microgravity environment, the phase separation due to the density difference between the solutions was eliminated. Since the effect of inertia due to and motion on the flow of liquid becomes relatively large,
After all, it became clear that different kinds of solutions were difficult to mix.

Therefore, as shown in FIG. 3, the inventors mixed the fluid 2 flowing in the vertical flow path 1 and the fluid 4 flowing in the horizontal flow path 3 at the intersection 5 having the T-shape, and then the horizontal direction. Channel 3
When flowing in the direction of,
It has been found that a vortex 6 is generated between the fluid 2 and the fluid 4 to allow stirring and mixing. (Japanese Patent Application No. 01-155213, June 15, 1991
(Japanese application)

[0009]

SUMMARY OF THE INVENTION It is not easy to automatically and evenly mix a small amount of a few milliliters of different kinds of solutions in a microgravity space such as the universe.

The inventor has found that when two kinds of fluids are supplied by using a container having narrowed vertical flow passages and intersecting with each other in a T-shape, vortices are generated and mixed. The challenge is to do it effectively.

[0011]

SUMMARY OF THE INVENTION The above-mentioned problem is solved in the longitudinal flow passage in which the fluid flowing in the vertical direction and the fluid flowing in the horizontal direction are mixed at the T-shaped intersection and flow in the horizontal direction. This can be solved by constructing a liquid mixing device in a weightless environment, characterized in that the inner diameter of is narrowed toward the intersecting portion and the longitudinal intersecting axis is eccentric.

[0012]

The present invention further promotes the stirring and mixing effect proposed by the inventors. That is, as a result of further study by the inventor in a microgravity environment caused by ballistic flight of an aircraft, in order to improve the mixing efficiency of mixing, the eccentricity of the joint position of the two pipes that intersect each other is formed. By doing so, it was found that the generation of vortices can be made more efficient.

FIG. 1 illustrates this relationship, and for ease of understanding, the same parts as those in the conventional structure of FIG. 3 are designated by the same reference numerals. That is, when the vertical flow path 1 and the horizontal flow path 3 intersect in a T-shape and the fluid 2 and the fluid 4 are mixed at the intersection portion 5, the inertia of the liquid has a great influence on the motion of the liquid. In addition, although the effect of stirring and mixing is greater when the flow passage 1 in the vertical direction is narrowed at the crossing portion 5, in this case, the position of the crossing portion 5 between the vertical flow passage 1 and the horizontal flow passage 3 is displaced from the center. It was found that it is more effective.

The inventor has previously found that the fluid 2 from the vertical flow passage 1 and the fluid 4 from the horizontal flow passage 3 generate a vortex 6 at the intersection 5, but the present invention is shown in FIG. As shown in (), the generation of the vortex 6 is promoted by eccentricizing the longitudinal flow path 1.

Since the influence of the inertia of the liquid is great under microgravity, it is preferable to flow a fluid having a high weight density into the flow passage 1 in the vertical direction in order to generate the vortex 6, and also in the flow passage in the vertical direction. No. 1 is more effective when narrowed at the intersection 5, but as a result of experiments, it was found that the condition is 2/3 or less of the diameter and that the diaphragm angle (θ) shown in FIG. It was found that the stirring and mixing efficiency was high.

[0016]

EXAMPLE A T-shaped flow path was prepared by using a transparent acrylic resin having an inner diameter of 1 mm and changing three kinds of the vertical flow path 1 and the horizontal flow path 3 having the same diameter as shown in FIG.

Here, the figure (A) is the one to which the present invention is applied, the figure (B) is the structure previously proposed by the inventor, and the figure (C) is the normal structure. As a microgravity environment, we used 0.01-0.02G for 20 seconds created by ballistic flight of NASA aircraft (KC-135).

Here, a protein solution (1.0% by weight of horse myoglobin) is used as the fluid 2 flowing through the vertical flow path 1, and an ammonium sulfate solution having a saturation degree of 50% is used as the fluid 4 flowing through the horizontal flow path 3. Was used, and a syringe pump (STC-521 manufactured by Terumo Corp.) was used as a liquid-feeding pump, and experiments were conducted while changing the liquid-feeding speed.

The mixing behavior was recorded on a video camera and subjected to analysis. As a measuring method, the rear part of the lateral flow path of the T-shaped tube was vertically branched, and a UV absorption measuring instrument was installed at the tip of each branch path to continuously measure the myoglobin concentration.

That is, the difference in myoglobin concentration between the upper and lower liquids was compared after mixing while changing the liquid feeding speed. In addition, the experimental equipment was equipped with a triaxial accelerometer to check the acceleration applied to the equipment.

Table 1 shows the results and shows the difference in myoglobin concentration. The apparatus A to which the present invention is applied has the highest agitation efficiency, and the apparatus B is subsequently effective, which is remarkable when the flow velocity is small. Is.

[0022]

[Table 1] In addition, when the myoglobin concentration difference was small and the mixture was well mixed, the generation of vortices could be observed.

[0023]

By implementing the present invention, it becomes possible to efficiently mix solutions in a weightless environment.

[Brief description of drawings]

FIG. 1 is a perspective view (A), a sectional view (B), and a front view (C) illustrating the present invention.

FIG. 2 is a cross-sectional view of an intersection of a T-shaped channel used in an example.

FIG. 3 is a perspective view (A) and a sectional view (B) of the mixing device proposed by the inventor earlier.

[Explanation of symbols] 1 longitudinal flow path 2, 4 fluid 3 lateral flow path 5 intersection 6 vortex

Claims (2)

[Claims] 1. A longitudinally flowing fluid (2) and a laterally flowing fluid (4) are mixed at a T-shaped intersection (5) to form a laterally flowing channel. A liquid mixing apparatus in a weightless environment, characterized in that the directional flow channel (1) is formed so that the inner diameter thereof is narrowed toward the intersection (5) and the cross axis of the vertical flow channel (1) is eccentric. 2. The fluid (2) is caused to flow in the vertical direction, the inner diameter of the vertical flow path (1) at the intersection (5) is not more than 2/3 of the unthrottled portion, and the throttle angle θ is 10 ° ≤ θ ≤ 6
The mixing apparatus for a liquid in a weightless environment according to claim 1, wherein the mixing apparatus is 0 °.