KR20170079791A - Cryogenic tank of cryogenic liquid and cooling apparatus and method - Google Patents

Abstract

A cryogenic liquid subcooling device within a cryogenic tank is disclosed.
Cryogenic liquid within the cryogenic tank disclosed The supercooling device comprises a cryogenic tank filled with cryogenic liquid; An ejector connected to the upper injection port of the cryogenic tank and injecting high-pressure gas into the upper portion of the cryogenic tank; And a helium injection member for injecting helium into the cryogenic liquid.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cryogenic tank for cryogenic liquid,

The present invention relates to a cryogenic liquid subcooling apparatus and method within a cryogenic tank.

More specifically, the high pressure gas is injected into the ejector to lower the pressure inside the cryogenic tank below atmospheric pressure to lower the temperature of the cryogenic liquid in the tank, and to promote the convection of the cryogenic liquid as the helium is injected from the bottom of the cryogenic tank Temperature liquid supercooling apparatus and method in a cryogenic tank capable of improving the supercooling efficiency of the liquid while reducing the amount of helium consumption by causing uniform temperature at the upper and lower portions and inducing supercooling by helium injection.

It should be noted that the contents described in this section merely provide background information on the present invention and do not constitute the prior art.

In the cryogenic propellant feed portion of the projectile, it is essential to precisely match the propellant feed temperature required by the engine. If the tank fill temperature of the cryogenic liquid oxygen can not be adjusted to the required temperature, the filling volume in the tank may increase and the propellant tank may become larger or the combustion time may be shorter. For example, when the propellant temperature is 100K, the charging volume increases by about 6% as compared with 90K.

In addition, cavitation may occur at the inlet of the turbo pump, resulting in poor pumping performance and, in severe cases, damage to the pump. The temperature of the propellant in the tank differs depending on the position in the tank, and usually becomes higher toward the upper (pressure side). It is therefore necessary to lower the temperature of the tank interior and the inlet feed line to the requirements via econditioning of the cryogenic propellant on the ground before launching the projectile.

Particularly, in the case of liquid oxygen charged in the main pipe, natural convection becomes less active due to a relatively high head pressure and a small pipe diameter. As the temperature rises continuously and bubbles occur rapidly, a geysering effect can occur which damages the tank and piping components.

In order to prevent such cavitation and gauzering effects, a method of maintaining the temperature of the cryogenic liquid below a predetermined level is required. For this purpose, a method of injecting helium gas is used.

Conventionally, a method of injecting only helium gas into the tank is adopted. However, this method has a problem in that the amount of helium required increases as the volume of the stored cryogenic liquid increases, so that the test equipment for the combustion test of the liquid rocket engine having a large tank capacity has a problem that the helium consumption is increased and the cost is greatly increased.

Prior Art 1: Open Patent Publication No. 10-2005-0051848 (Published on June 2, 2005)

The object of the present invention is to reduce the temperature of the cryogenic liquid in the tank by lowering the pressure inside the cryogenic tank to below atmospheric pressure as the high pressure gas is injected into the ejector and to cause the convection of the cryogenic liquid The present invention provides a cryogenic liquid supercooling device in a cryogenic tank capable of improving the supercooling efficiency of liquid while reducing the amount of helium consumption by promoting the temperature of the upper and lower portions and inducing supercooling by helium injection.

Another object of the present invention is to provide a supercooling method using the above-mentioned cryogenic liquid supercooling apparatus.

According to one aspect of the present invention, there is provided an ejector comprising: an ejector connected to an upper injection port of a cryogenic tank and serving to lower a temperature of a cryogenic liquid by lowering a pressure inside the cryogenic tank below atmospheric pressure upon injection of a high pressure gas; And a helium injection member for injecting helium into the cryogenic liquid. The cryogenic liquid supercooling apparatus is provided within the cryogenic tank.

The present invention is preferably such that the helium injection member comprises: a helium tank in which helium is stored; An injection nozzle installed at an inner bottom of the cryogenic tank; And a connection pipe connecting the helium tank and the spray nozzle.

According to another aspect of the present invention, there is provided a method of controlling a temperature of a cryogenic liquid tank, comprising the steps of: lowering a pressure inside a cryogenic tank to below atmospheric pressure as a high pressure gas is injected into an ejector connected to an upper portion of a cryogenic tank filled with cryogenic liquid, A method of supercooling a liquid in a cryogenic liquid tank inside the cryogenic tank, which promotes the convection of the cryogenic liquid by injecting helium into the inner lower portion of the cryogenic tank and uniformizes the temperature at the upper and lower portions thereof and causes the supercooling by the helium injection.

According to the present invention, as the high-pressure gas is injected into the ejector, the pressure inside the cryogenic tank is lowered to atmospheric pressure or less to lower the temperature of the cryogenic liquid in the tank, and the convection of the cryogenic liquid Thereby promoting the uniformity of the temperature of the upper and lower portions thereof, and simultaneously inducing the supercooling by the helium injection, thereby improving the supercooling efficiency of the liquid while reducing the amount of helium consumption.

1 is a schematic diagram of a cryogenic liquid supercooling device inside a cryogenic tank

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The terms used in the present invention are defined in consideration of the functions of the present invention and may vary depending on the intention or custom of the user or the operator. Therefore, the definitions of these terms are meant to be in accordance with the technical aspects of the present invention As well as the other.

In addition, optional terms in the following embodiments are used to distinguish one element from another element, and the element is not limited by the terms. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, detailed description of related arts which may unnecessarily obscure the gist of the present invention will be omitted.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of a cryogenic liquid supercooling apparatus within a cryogenic tank.

1, a cryogenic liquid supercooling device in a cryogenic tank according to the present invention is connected to an upper injection port 110 of a cryogenic tank 100 filled with a cryogenic liquid, An ejector 200 for lowering the pressure inside the tank 100 to atmospheric pressure or lower and consequently lowering the temperature of the cryogenic liquid and a helium injection member 300 for injecting helium with the cryogenic liquid.

In addition, if the temperature of the cryogenic liquid filled in the cryogenic tank 100 is not constant, the cavitation phenomenon at the inlet of the turbo pump in the liquid rocket engine and the evaporation of the cryogenic fluid at the inlet of the cryogenic tank 100, A gypsum ring effect that damages the parts is generated. To this end, conventionally, only the helium gas is injected into the cryogenic liquid to supercool the cryogenic liquid below the saturation temperature.

However, according to the present invention, as the high pressure gas is injected into the ejector 200, the static pressure inside the ejector 200 drops below the atmospheric pressure, and the cryogenic tank connected to the ejector 200 The liquid in the cryogenic tank 100 is discharged to the ejector 200 through the ejector 200. As a result, the pressure inside the cryogenic tank 100 drops below atmospheric pressure and the temperature of the cryogenic liquid drops .

Helium is injected into the lower part of the inside of the cryogenic tank 100 by the helium injection member 300 and the temperature of the upper and lower parts of the cryogenic liquid is made uniform by stirring the cryogenic liquid by the jetting force The supercooling due to the helium injection is generated at the same time as the zooming, so that the cryogenic liquid can be supercooled quickly and generally, and the consumption of the expensive helium can be remarkably reduced compared to the prior art.

The helium injection member 300 includes a helium tank 310 in which helium is stored, an injection nozzle 320 disposed in an inner bottom of the cryogenic tank 100, And a connection pipe 330 connecting the connection pipe 320 with the connection pipe 330.

Here, the injection nozzle 320 may include a ring-shaped spray tube 321 and a plurality of spray holes 322 provided on the upper surface of the spray tube 321. The injection holes 322 may have different pores to facilitate the convection of the cryogenic liquid.

In this case, the amount of helium injected through each of the spray holes 322 having different sizes becomes different, and the injection force thereof also becomes different, so that the stirring (convection) of the cryogenic liquid can be further promoted.

An upper connection pipe 120 connecting the ejector 200 to the upper injection port 110 of the cryogenic tank 100 and a connection pipe 120 connecting the helium tank 310 and the injection nozzle 320 330 may be provided with an on-off valve v for opening and closing each channel. The on / off valve (v) can selectively block high pressure gas or helium injected into the cryogenic tank (100) by opening and closing each channel as necessary.

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not to limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: Cryogenic tank 110: Upper inlet
200: Ejector 300: Helium injection member
310: helium tank 320: injection nozzle
330: Connector

Claims (3)

An ejector connected to the upper injection port of the cryogenic tank and serving to lower the temperature of the cryogenic liquid by lowering the pressure inside the cryogenic tank below atmospheric pressure upon injection of the high pressure gas; And
A helium injection member for injecting helium into the cryogenic liquid;
A cryogenic liquid supercooling device within a cryogenic tank.
The method according to claim 1,
The helium injection member
A helium tank in which helium is stored;
An injection nozzle installed at an inner bottom of the cryogenic tank; And
A connecting pipe connecting the helium tank and the spray nozzle;
A cryogenic liquid supercooling device inside a cryogenic tank.
Temperature tank, the temperature of the cryogenic liquid is lowered by lowering the pressure inside the cryogenic tank to below atmospheric pressure as the high-pressure gas is injected into the ejector connected to the upper part of the cryogenic tank filled with the cryogenic liquid, To thereby promote the convection of the cryogenic liquid to uniformize the temperatures at the upper and lower portions thereof and to cause the supercooling by the injection of the helium into the cryogenic liquid tank.

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