DE2237360A1 - METHOD OF REDUCING THE COEFFICIENT OF FRACTION OF THE MATRIX CORE OF A ROTATING HEAT EXCHANGER - Google Patents

Description

Method of reducing breakage 2237360 leo coefficients of the matrix kernel of a

rotatable heat exchanger. /: "

The invention relates to rotatable heat exchangers with a rotatable disk-like matrix having a foraminous core of silicon nitride, the one Has a plurality of flow passages with open ends, which are essentially to the axis of rotation of the matrix.

Heat exchangers of this type are used in power plants with gas turbines to extract heat from the exhaust gases and to add it to the compressed supply air before it enters the combustion chamber of the gas turbine engine.It is of course necessary to keep the two gaseous heat exchange flows constantly separated from one another and the exit between the upper part of the mountain, which is occupied by the compressed supply air, is occupied by the exhaust gases! Low-

to communicate dfuckzoöe. So far you have this

end seals used j those with the correspondence / surface make frictional contact with the matrix. The for

the heat exchange! - ⁶ IrI ¹ order of force and the rate of eternity of the seals largely depends

Was the filling of the seal as well as the fracture coefficients— part between seal and washer.

Of? SS ** f £ Sittittg is an object _f the Bruchkoeffi ^ ietiten of Siliciumnitridkerns to reduce "Zttr Lostwtg this object the invention is characterized% $ & etift £ s £ EHN @ i t that the matrix core metalliechert with a Galas impregnated and then the salt is up to $ _as oxide mined. The metal oxide is preferably chromium oxide, cobalt oxide, copper oxide or zinc oxide in an amount between 2 percent and 10 percent of the matrix core to be impregnated.

The invention is carried out in a simple and effective manner by placing the matrix core in an aqueous Solution of the metallic salt brought to the boil

3098U / 0726

and then it is cooled down to room temperature i the matrix core is impregnated for at least one hour at this temperature / and then heated in air to a temperature between 300 C to about 800 C, depending on the salt used,

to the '\ · ν ■ ~ · , ■■><■■; ,. ■

to break down the salt to / oxide. If, for example, the metallic salt used to impregnate the matrix core is chromium nitrate, cobalt nitrate or copper nitrate, the mentioned subsequent heating of the matrix core in air is carried out at temperatures between% 00 ° C. and 500 ° C. If the salt used is zinc nitrate, the temperature for the subsequent one is heating the matrix core i _n ^a air 300 C to 00 ° C.%

309 8U / 0726

- Expectations

ORIGINAL INSPECTED

Claims (12)

July 26, 1972 Q British Leyland Truck and Gu / gm Bus Division Limited Expectations Method of reducing the coefficient of rupture of the matrix core of a rotatable heat exchanger, characterized in that the matrix core is impregnated with a metallic salt and then on the
the salt until / oxide is broken down. 2. The method according to claim 1, characterized in that the oxide is chromium oxide in an amount of 2 % to 10 % of the weight of the matrix core to be impregnated. " 3 «Method according to claim 1, characterized in that the oxide is cobalt oxide in an amount of 2 % to 10 % of the weight of the matrix core to be impregnated. - k. Process according to Claim 1, characterized in that the oxide is zinc oxide in an amount of 2 % to 10 % of the weight of the matrix core to be impregnated. 5. The method according to claim 1, characterized in that the oxide is copper oxide in a Mege of 2 % to 10 % of the weight of the matrix core to be impregnated. 6. The method according to any one of the preceding claims, characterized in that the matrix core in an aqueous Solution of the metallic salt brought to the boil and then cooled down to room temperature in which it is impregnated for at least one hour ^ and then by subsequent 309814/0726 the heating is brought in air to a temperature between 300 ⁰ C and about 800 ° C, the salt up to de "oxide dismantle · 7. The method according to any one of claims 2 to 6, characterized in that said salt is chromium nitrate and that the subsequent heating takes place in air at a temperature between 400 ° C and 500 ⁰ C. · 8. The method according to any one of claims 3 *** · ^ t thereby characterized in that the salt let cobalt nitrate and that the subsequent heating in air at a Temperature between 400 C and 500 C takes place 9 · Method according to one of Claims 4 to 6, characterized characterized in that the salt is zinc nitrate and that the subsequent heating takes place in air at a temperature between 500 ° C and 400 ° C. 10. The method according to any one of claims 5 to 6, characterized in that the salt is copper nitrate and that the subsequent heating takes place in air at a temperature between 400 ° C and 500 ° C. 11. Use one after one of the procedures according to • Claim 1 to Claim 10 treated matrix core in a rotatable heat exchanger · ' 12. Rotatable heat exchanger, characterized in that the matrix core by the method according to a of claims 1 to 10 has been dealt with. The patent attorney 309814/0726