JPH01274803A - Device for initiating crystallization for supercooled liquid - Google Patents

Abstract

PURPOSE:To repeat sure crystallization by allowing the fine ruggednesses formed on the opposed surfaces of opposed crystallization initiators to collide with or rub on one another by a driving means to stimulate a supercooled liq. between the ruggednesses. CONSTITUTION:When a plate spring 6 is pressed downward by optional electrical, mechanical means and so on, the ruggedness 4 of the second crystallization initiator 5 fixed to the tip of the spring 6 collides instantaneously with the ruggedness 2 of the opposed first crystallization initiator 3. At the time of collision, a stress is concentrated on minute regions of the supercooled liq. in the vicinity of the tip of the protrusion, the stress acts as a stimulus, and crystallization is immediately initiated from the regions. When the plate spring is made of stainless steel, the spring is not corroded by the supercooled liq., and the force from a driving means can be repeatedly transmitted to the crystallization initiator 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to an apparatus for applying stimulation to a supercooled liquid to initiate crystallization.

(Prior Art) Heat storage materials using hydrated salts, such as sodium acetate trihydrate, which transfer and receive heat through phase changes of solidification and melting, have been known.

In such a heat storage material, the hydrated salt usually releases crystal water when heated, becomes a liquid and absorbs latent heat 17, and when cooled, it takes in the crystal water, solidifies, and releases latent heat. When latent heat is to be released, a seeding agent (1) which becomes a seed for crystallization is usually added to the supercooled liquid.

■ Add ultrasonic vibration.

■ Apply voltage.

■ Apply mechanical shock.

It is said that stimulation is applied by various means such as to initiate solidification and crystallization, thereby dissipating heat.

(Problems to be Solved by the Invention) However, in these conventional methods, it is difficult to apply the seeding agent (1) in a closed system.
．． However, the method of applying ultrasonic vibration in (2) requires high output when the liquid has a high viscosity, and the reliability of crystallization is low. The method of applying voltage has the problem that chemical changes occur on the electrode surface, making it difficult to repeatedly apply voltage and achieve stable crystallization. Impact devices of various shapes and structures have been proposed, but all of them have problems in that they lack certainty in the initiation of crystallization and that their functionality deteriorates due to repeated heating and cooling.

The present invention has been made to solve these problems, and provides a crystallization initiation device for supercooled liquids that can reliably initiate crystallization and does not cause any deterioration in performance even after repeated use. The purpose is to

[Structure of the Invention] (Means for Solving the Problems) The crystal for supercooled liquid of the present invention includes a pair of crystallization initiators each having a large number of minute irregularities formed on its main surface, and a motion suppressing reference body for suppressing the motion of the supercooled liquid, which is fixed to one side of the body with its main surface facing outward; It is characterized by comprising a driving means for causing a surface to collide with the main surface of the crystallization initiator fixed on the motion suppressing reference body.

In the present invention, formed on the opposite surface of the crystallization initiator,
The size of the unevenness is preferably about the same as the size of crystals to be crystallized, and is usually from 1 μm to several 100 μm in size. To form these minute irregularities, there is a method of etching the surface of the metal chip, but it is also possible to form the desired irregularities simply by roughening the surface finish.

Note that parts that function while immersed in supercooled liquid, such as the motion control reference body and the crystallization starter, are made of materials such as stainless steel, which are not corroded by this liquid and whose characteristics hardly change when heated. This is desirable. Further, as the driving means used in the present invention, it is possible to drive at least one of the crystallization initiators at a sufficient speed so that these irregularities are brought into contact such as colliding or sliding together instantaneously and with sufficient impact force. Spring members, plungers, fluid cylinders, and any other possible means may be used.

(Function) In the crystallization initiator for supercooled liquid of the present invention, minute irregularities formed on the opposing surfaces of the opposing crystallization initiators are instantaneously collided or rubbed together by the driving means, and Stimulates the supercooled liquid in a micro region. Therefore, crystallization starts simultaneously and quickly from a large number of scattered micro regions.

In addition, since the movement and flow of the supercooled liquid is suppressed by the motion suppression reference body, even in the case of highly viscous liquid, the stress generated by contact between uneven surfaces is transmitted to the supercooled liquid without being attenuated. Crystallization begins.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing an embodiment of the crystallization initiation device for supercooled liquid of the present invention.

In the figure, reference numeral 1 indicates a liquid movement suppressing reference body having a U-shaped cross section, and the main surface of this movement suppressing reference body 1 has a large number of minute particles on the surface, as shown in an enlarged view in FIG. A first crystallization initiator 3 on which groove-like unevenness 2 is formed is fixed upward. In addition, the second crystallization initiator 5 having similarly minute irregularities 4 formed on its surface is made of stainless steel leaf spring 6.
It is attached to the tip of the crystallization initiator 3 and is arranged to face the crystallization initiator 3 side. The leaf spring 6 is capable of assuming two stable states of upward or downward bending under internal stress. The crystallization initiating body 5 collides with the crystallization initiating body 3 when the crystallization initiating body 5 collides with the motion suppressing reference body 1 when the crystallization initiating body 5 is curved downward.
Fixed on top. This leaf spring 6 is pressed from above as shown by the arrow by an electrical, mechanical or other arbitrary driving means to cause the crystallization initiator 5 to collide with the crystallization initiator 3, and is also pressed from below. It is configured to repeatedly perform the operation of returning to the original position.

In the supercooled liquid crystallization initiator of the embodiment having such a structure, when the leaf spring 6 is pushed downward by the driving means, the second crystallization initiator attached to the tip of the leaf spring 6 is pressed downward. The unevenness 4 of No. 5 instantaneously collides with the opposing unevenness 2 of the first crystallization initiation body 3. During this collision, a concentrated stress 17 is applied to minute regions of the supercooled liquid near the tip of the convex portion, and this stress acts as a stimulus, causing crystallization to begin immediately from these regions. In this embodiment, the leaf spring 6 is made of stainless steel, so it will not be corroded by the supercooled liquid, and the force from the driving means can be applied repeatedly. It can be transmitted to the crystallization initiator 5. Furthermore, since the crystallization initiation body 3.5 is surrounded by the motion suppression reference body 1 having a U-shaped cross section, the motion of the supercooled liquid is restricted by the motion suppression reference body 1, and the leaf spring 6, etc. The liquid does not move following the movement of. Therefore, the stress caused by the collision of the unevenness is directly transmitted to the nearby supercooled liquid, thereby ensuring the initiation of crystallization.

Next, a specific example will be shown in which crystallization of a supercooled liquid is started using the apparatus of this embodiment.

That is, a heat storage material in which polyacrylamide-acrylic acid copolymer was added as a phase separation inhibitor at a ratio of 1% by weight to sodium acetate and trihydrate was sealed in a polyethylene container together with the apparatus of the example. . This was heated to 80°C to turn the heat storage material into a liquid state. Next, after cooling to room temperature and bringing it into a supercooled state, the drive means of the device of the example was activated to cause the unevenness 2.4 on the opposing surface of the crystallization initiation body 3.5 to collide with each other. Crystallization started in the vicinity, and the temperature rose to 55-58°C due to the release of latent heat.

In the above example, the top and bottom of the unevenness 2.4 on the surface facing the crystallization initiation body 3.5 were formed into a relatively gentle shape, but they may also be formed into a sharp sawtooth shape as shown in FIG. can. When this shape is adopted, in addition to the impact caused by collision, the friction caused by sliding on the inclined parts is also applied as a stimulus to the supercooled liquid, which makes it easier to concentrate stress in a smaller area. This has the advantage of increasing the reliability of crystallization initiation.

[Effects of the Invention] As explained above, the crystallization initiation device for supercooled liquids of the present invention can quickly and reliably crystallize supercooled liquids such as inorganic or organic hydrated salts. can be started. In addition, performance and reliability do not deteriorate even after repeated use.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a front view showing an embodiment of the crystallization initiator for supercooled liquid of the present invention, FIG. 2 is an enlarged perspective view of the crystallization initiator in FIG. The figure is an enlarged perspective view showing another example of a crystallization initiator. 1...Motion suppression reference body 2.4...Irregularities 3.5...Crystallization initiation body 6...Plate spring

Claims (1)

[Claims] (1) The operation of a pair of crystallization initiators with many minute irregularities formed on their main surfaces, and a supercooled liquid in which one of the crystallization initiators is fixed with its main surface facing outward. A motion suppressing reference body to be suppressed and the other of the crystallization initiating bodies are fixed to the motion part, and the main surface of the crystallization initiating body collides with the main surface of the crystallization initiating body fixed on the motion suppressing reference body. 1. A crystallization initiation device for a supercooled liquid, comprising: a driving means for causing a supercooled liquid.