RU2797894C1 - Radiant hybrid structure panel - Google Patents

Abstract

FIELD: space technology.

SUBSTANCE: hybrid structure radiant panel consists of a hybrid structure, the top plate of which is a metal panel with an outer radiating layer, the bottom plate is a hybrid structure composed of a stack of graphite films with an in-plane thermal conductivity of more than 1500 W/(mK). The plates are fixed with adhesive. Metal elements are installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel, increasing the out-of-plane thermal conductivity of the panel.

EFFECT: increased efficiency of heat discharge into outer space while simplifying the design without heat pipes.

4 cl, 4 dwg

Description

The invention relates to space technology, in particular to devices that remove excess heat from fuel elements of equipment due to radiant heat exchange. The invention can be used in the design of planetary bases and spacecraft.

Radiant panels are used to remove excess heat from the fuel elements of the equipment installed on it, due to radiant heat transfer to the surrounding space.

Various designs of radiant panels are known. For example, a radiant panel known from RU 2603690 C1, 11/27/2016, which includes a radiator-emitter in the form of a cylindrical screen made of metal and heat pipes on the screen surface, or RU 2329922 C2, 07/27/2008, which is a radiator - emitter made of honeycomb panel with heat pipes built into it. A significant disadvantage of the above solutions is that the currently used axial heat pipes are not adapted to work in gravitational conditions on planetary bases, and are made of metal or spatial honeycomb panels, and therefore have a large mass. The closest analogue is the radiating panel, known from RU 2603690 C1, 11/27/2016.

The disadvantages of the closest analogue include the following:

- the presence in the design of the radiative heat exchanger of heat pipes that do not work effectively in gravitational conditions;

- the use of a single-layer radiating metal panel, which leads to a weighting of the structure;

- the presence of heat pipes increases the likelihood of deterioration of the operating parameters of the radiation emitter due to meteorite breakdown.

The objective of the invention is to eliminate the above disadvantages and obtain a new design of the radiant panel.

To solve the problem and ensure the technical result, a radiant panel of a hybrid structure is proposed, consisting of two plates, the upper plate of which is a metal plate, the lower plate is a hybrid structure of highly conductive pyrolytic graphite foil, connected by adhesive gluing, the plates are fixed by adhesive bonding, on the radiating panel perpendicular to the radiating surface on the entire area of the panel through the thickness of the panel installed metal elements that increase the out-of-plane thermal conductivity of the panel. The top plate of the radiant panel is made of aluminum or steel. A radiating layer is deposited on the outer surface of the top plate of the radiating panel.

The radiant panel of the hybrid structure consists of two layers, the upper one is radiant and the lower one is heat-conducting.

The upper radiant layer of the hybrid structure radiant panel is made of metal.

The lower heat-conducting layer of the radiant panel of the hybrid structure consists of a package of highly conductive pyrolytic graphite foil.

There are no heat pipes in the design of the hybrid structure radiant panel.

The present invention is illustrated by graphic images.

In FIG. 1 shows a diagram of a radiant panel of a hybrid structure with a two-layer radiant panel with fuel elements of the equipment located on it.

In FIG. 2 shows metal elements installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel in the form of rivets.

In FIG. 3 shows metal elements installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel in the form of a wire seam.

In FIG. 4 shows metal elements installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel in the form of wire brackets.

The radiant panel of the hybrid structure, fig. 1 consists of two plates, 1 and 2. The top plate - 1 consists of metal with an outer radiating layer. The bottom plate - 2 is a hybrid structure consisting of a package of highly conductive pyrolytic graphite foil with in-plane thermal conductivity of more than 1500 W / (mK), which reduces the weight and increases the efficiency of the radiating panel fin. Fuel elements of the equipment 3 are installed on the bottom plate. Metal elements 4 are installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel, increasing the out-of-plane thermal conductivity of the panel.

The bottom plate of the radiant panel of the hybrid structure is assembled from a highly conductive pyrolytic graphite foil. The foil production process uses carbonized polymer films and high temperature heat treatment. By optimizing the heat treatment conditions, it is possible to obtain a foil with high thermal conductivity values in the in-plane direction. The maximum thickness of the sheets is no more than 25 microns. The stack of highly conductive pyrolytic graphite foil is assembled by adhesive gluing. The thermophysical properties of highly conductive pyrolytic graphite foil make it possible to use them in a wide temperature range. The use of a hybrid package of pyrolytic graphite foil as the lower highly conductive layer of the radiating panel leads to a significant increase in in-plane thermal conductivity, which, in turn, makes it possible to refuse the use of heat pipes in the design. The absence of heat pipes in the design makes it possible to effectively use the radiative heat exchanger in systems for ensuring the thermal regime of planetary stations in gravitational conditions.

The proposed invention is characterized by high structural strength, and the use of a hybrid stack of pyrolytic graphite foil, according to the invention, makes it possible to reduce the mass characteristics of the radiating panel while increasing the efficiency of heat discharge into outer space.

The device works as follows. The elements of the equipment 3 generate heat, which leads to an increase in their temperature. The heat flux from the equipment elements 3 is transferred to the radiating panel 1, 2. Due to the high in-plane thermal conductivity of the hybrid package of pyrolytic graphite foil 2, the heat is uniformly distributed over the radiating plate 1. The radiating plate 1 removes the heat flow coming from the equipment elements by radiation into the surrounding outer space 3, thereby lowering their temperature. The metal elements 4 provide an increase in the out-of-plane thermal conductivity of the panel.

= 0,6. Удельная масса панели составляет 0,08 кг/

. Удельная масса отводимого тепла 0,04 кг/Вт. Чем меньше удельная масса панели и удельная масса отводимого тепла, тем эффективнее устройство. В случае отказа от тепловых труб и использования гибридной излучающей панели для отвода тепла от тепловыделяющих элементов оборудования на основе графита, аналогичная эффективность ребра излучающей панели достигается при удельной массе панели 0,065 кг/

и удельной массе отводимого тепла 0,032 кг/Вт, что на 20 % меньше, чем при использовании излучающей панели с тепловыми трубами. Отказ от тепловых труб в конструкции гибридной излучающей панели приводит к отсутствию вероятности пробоя тепловых труб метеоритами и, как следствию, повышению надежности работы агрегата. Кроме того, переход на гибридные излучающие панели позволяет преодолеть трудности использования аксиальных тепловых труб в поле гравитации, например, при проектировании системы обеспечения теплового режима лунной базы. Как видно из приведенных данных, предлагаемое изобретение обеспечивает более эффективный сброс тепла в космическое пространство, чем известные конструкции того же назначения.To remove heat from the fuel elements of equipment, radiant panels with axial heat pipes installed on them are currently used to increase the efficiency of the fin. On the heat-insulated side of the panel there are fuel elements of the equipment and heat pipes, the reverse side of the panel is radiant. The distance between the heat pipes is 0.15 m, the weight of a linear meter of the heat pipe is 0.3 kg/m. The rib efficiency of the panels used is

= 0.6. The specific gravity of the panel is 0.08 kg/

. The specific mass of the removed heat is 0.04 kg/W. The lower the specific gravity of the panel and the specific gravity of the heat removed, the more efficient the device. In the case of abandoning heat pipes and using a hybrid radiant panel to remove heat from the fuel elements of graphite-based equipment, a similar efficiency of the radiant panel fin is achieved with a specific weight of the panel of 0.065 kg /

and the specific mass of the removed heat is 0.032 kg/W, which is 20% less than when using a radiant panel with heat pipes. The rejection of heat pipes in the design of the hybrid radiant panel leads to the absence of the possibility of breakdown of heat pipes by meteorites and, as a result, to an increase in the reliability of the unit. In addition, the transition to hybrid radiant panels makes it possible to overcome the difficulties of using axial heat pipes in a gravitational field, for example, when designing a system for ensuring the thermal regime of a lunar base. As can be seen from the above data, the proposed invention provides a more efficient release of heat into outer space than the known designs of the same purpose.

Claims (4)

1. The hybrid structure radiant panel, consisting of two plates, the upper plate is made of metal, the lower plate is a hybrid structure of highly conductive pyrolytic graphite foil bonded by adhesive bonding, the plates are fixed by adhesive bonding, on the radiant panel perpendicular to the radiant surface over the entire area of the panel metal elements are installed through the thickness of the panel. 2. The radiant panel of the hybrid structure according to claim 1, characterized in that the top plate of the radiant panel is made of aluminum or steel. 3. The radiating panel of the hybrid structure according to claim 1, characterized in that a radiating layer is applied to the outer surface of the upper plate of the radiating panel. 4. The radiating panel of the hybrid structure according to claim 1, characterized in that the metal elements installed on the radiating panel perpendicular to the radiating surface over the entire area of the panel through the thickness of the panel are wire staples, or rivets, or a wire seam.

Images