JP2834125B2 - Multi-layer thermal insulation structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a blocking and fitting structure between a member made of a heat-resistant material exposed to a high temperature and a member having a low allowable temperature, and is particularly effective in a narrow gap layer. The present invention relates to a multi-layer heat shielding structure that forms a typical heat shield. [Prior Art] Conventionally, there is a ceramic coating as an example of heat shielding protection of a low heat-resistant allowable temperature (for example, heat-resistant alloy). In this example, ceramic powder is applied to the surface of a material directly exposed to high temperature by plasma coating or the like.
It has the feature that a solid connection can be expected. However, in a coating, it is known that a temperature drop of about 50 ° C. can be realized with a coating layer having a thickness of about 0.3 mm, while it is known that formation of a thick coating layer is extremely difficult. This type of apparatus is described in JP-A-58-20902. [Problems to be Solved by the Invention] Since the above-mentioned conventional technology is only applied to the surface of the part to be protected, a temperature difference of about 100 ° C. can be realized finally with a coating of 0.5 mm thickness. It is not based on the idea of preventing heat input to the parts. This is an excellent method in terms of obtaining a heat shielding effect without taking up a large space.However, since the members are directly exposed to high temperatures, they are severely damaged when the coating is peeled off. However, it was difficult to achieve a temperature drop of 100 ° C or more, and there were problems such as cooling from the back side of the coating surface. An object of the present invention is to realize a temperature drop of about 1000 ° C. in a gap of several mm without directly exposing the material to a high temperature. [Means for Solving the Problems] The above-described object is to cut off radiant heat from a heat-resistant material member to an adjacent member in a low-heat-resistant material fitted with a heat-resistant member directly exposed to a high temperature, and to prevent the heat-resistant member from This is achieved by preventing heat input. It is effective to arrange a solid heat insulating material having many voids to block the radiant heat, and to arrange a heat resistant fiber layer and an air layer on the surface of the solid heat insulating material to prevent heat transfer to the low heat resistant member. [Action] The multilayer heat insulation structure according to the present invention comprises a solid heat insulation material, a heat-resistant fiber layer, and an air flow path layer. Radiant heat from the heat-resistant material can be shielded by the solid heat-insulating material laminated on the surface of the heat-resistant material. On the other hand, the heat transfer from the heat-resistant material is such that the heat-resistant fiber layer laminated on the surface of the solid heat-insulating material becomes a heat-shielding layer having an extremely low thermal conductivity including air, and further increases the heat transfer from the surface of the heat-resistant fiber layer. The air can be cut off by being discharged to the outside by air flowing through the air flow path layer provided on the surface of the heat resistant fiber layer. [Embodiment] One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a heat shielding layer formed between a heat-resistant material 1 such as fine ceramics and a low heat-resistant material 5 such as a metal material. The heat shielding layer is a solid heat insulating material 2, a heat-resistant fiber layer. This is an embodiment of the present invention, which is composed of the air flow path layer 4 and the air flow path layer 4. The solid heat insulating material 2 includes, for example, mullite ceramics 2 and the heat-resistant fiber layer 3 includes, for example, fibers made of ceramic fiber. FIG. 2 shows a schematic diagram of the cross section of FIG. First
The air flow path layer 4 shown in the figure can be practically formed by providing a groove 4 ′ on the inner surface of a material having low heat resistance and guiding cooling air or the like to the portion. Similarly, as shown in FIGS. 3 and 4, a protrusion 7 is provided between the heat-resistant fiber layer 3 and the material 5 having low heat resistance.
And a space 8 formed between the projection 7 and the surface of the material 5 having low heat resistance can be configured as a cooling air flow path. Also, as shown in FIG. 5, it is possible to provide a corrugated plate in place of the plate having the protrusions in FIG. [Effects of the Invention] The present invention has the following effects. That is, as the heat shielding element, a solid heat shielding material having excellent heat resistance is arranged on a member which is in direct contact with a heat-resistant material (for example, laceramics) exposed to a high temperature and receives strong radiant heat. When heat is transferred from a heat-resistant material having a high temperature to a material having low heat resistance, heat is removed from the surface of the material by an air flow just before the heat is input to the material. In addition, since the heat-resistant fiber layer arranged in the middle has a structure containing air and forms a layer with extremely low thermal conductivity, it is extremely efficient to block radiant heat and heat transfer as a whole and protect low heat resistant materials from heat. There is an effect that a good heat shielding layer can be formed. Furthermore, since each member constituting the present invention effectively utilizes each characteristic, it is expected that effective heat shielding characteristics can be obtained with an extremely thin layer as a whole.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of one embodiment of the present invention, FIG. 2 is an embodiment embodying a cooling air flow path, and FIG. 3 is a cooling flow path formed by a plate having projections. FIGS. 4 and 5 are cross-sectional views of the embodiment provided, and are external views of a plate-like member used for forming a cooling channel. 1 ... heat-resistant material, 2 ... solid heat-insulating layer, 3 ... heat-resistant fiber layer, 4 ... air flow path layer, 5 ... metal material.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobu Hisamatsu 2-6-1 Nagasaka, Yokosuka City, Kanagawa Prefecture Inside the Central Research Institute of Electric Power Industry, Yokosuka Research Institute (72) Inventor Hiroshi Miyata 502, Kandamachi, Tsuchiura City, Ibaraki Prefecture Shares (72) Inventor Shiro Iijima 4026 Kuji-cho, Hitachi City, Ibaraki Pref. Hitachi, Ltd. Hitachi Research Laboratories (56) References JP-A-62-48903 (JP, A) JP-A-50-74809 (JP, A) Japanese Utility Model Showa 60-166412 (JP, U) Japanese Utility Model Showa 58-144193 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F01D 9/02 F01D 5 / 28

Claims (1)

(57) [Claims] A multilayer in which a heat-resistant member exposed to high temperature, a solid heat-insulating material, a heat-resistant fiber layer, an air flow path layer, and a low heat-resistant member required to be maintained at a certain allowable temperature or lower are laminated in this order. A heat insulation structure, wherein the air flow path layer is formed by a groove provided on a surface of the low heat resistant member on the fiber layer side.