Combustion chamber construction

853,133. Generating combustion products under pressure; tube walls for furnaces. NAPIER & SON Ltd., D. Jan. 27, 1959 [Feb. 13, 1958], No. 4818/58. Class 51 (1). [Also in Groups XXVI and XXVIII] A combustion chamber 14, Fig. 1, of non-uniform crosssection is formed from a series of abutting flat tubes 17 of rectangular cross-section extending generally in the axial direction of the chamber and each comprising inner and outer plate-like members profiled along at least one flank to correspond with variations in the cross-section of the chamber along its axis, and two shallow flank elements at opposite edges of the tube, at least part of each flank element being formed as a rib adjacent the edge of and forming part of one of the plate-like members. The rib of each member is united as by welding to the edge or rib of the other plate-like member to form a fluid-tight tube and adjacent tubes are secured to one another along their flank edges. In Fig. 2, a platelike member 18 has a central rib 21 and edge ribs 19, 20 welded to a plate-like member in two parts 22, 23. In Fig. 4, the radially inner plate-like member 31 is of channel section and the outer member 32 is flat. In a further modification, both plate-like members are made of L-section plates. Each tube is bent to conform to the desired profile of the combustion chamber in a plane through the axis thereof. A coolant such as liquid hydrogen peroxide has access to the tubes through a gallery 28, Fig. 1, and leaves by a gallery 29 whence it passes through a passage 30 to the catalyst chamber 10 of a liquid-fuelled rocket motor.