A high efficiency heat interchanger design exists, known by having circa 1 mm layers of plates, with 0,1 mm etched flow canals in tha surfaces. The 1 mm layers of metallic plates are stacked, and the flow patterns are alternated in access to the layer matrix, from opposing and adjacent faces, according
to the internal etchings lay-outs of the flow canals.
This results in pure laminar flow thermal interchange, in a volumetrically highly efficient / compact, heat inter-changer.
My idea is that between these layers of flow canals of minimum two different fluids/liquids, are inserted a slightly thicker layer, say 2-7 mm's, with like 15 - 45 mm's diameter holes drilled or stamped through the thicker layer plate.
The function would then be, that these internal holes, are supplyed, and vacated, from the other layers, so that a burning (oxidation), or simply a mixing, or some other reaction, would be installed and formed.
The geometry could be a quadratic cube, or a brick like rectangle, or even a 'radial' flow cylinder, with a concentrical hole inside the cylindrical 'thick' shell. The exhausts could then be formed on either the internal face, or the outer shell surrounding surface.
The mixing/oxidation/other reaction, would result in a mechanical pressure 'flow', that would be taken to utility in a colder, constant temperature, simple lubrification, 'steam' engine type, mechanical drive shaft power device, of any configuration.
The issues in favor of this, conceptually outlined albeit, systems design, would be that :
1. Only laminar flows in the 'burn' process,
2. High freedom of optimization of volumes and flow paths in 'burner',
3. Compact, self-contained, mechanical burner design,
4. No moving parts in 'HOT' section of energy conversion, allowing material constants to be determined purely from 'presure' and 'constant operating temperature',
5. Pure pressure connection to mechanical drive assembly, near ambient temperatures for mechanically/dynamically stressed components,
5.1. i.e. low temperature lubrification, = no residue build up issues, low tech oil can be administered,
5.2. Highest strength of conventional engine component materials are expected at ambient temperatures, hence higher rpm / lower component 'thicknesses' are inherently to be designed. This gives lower weight, for same power/ and torque to drive shaft.