Well, since you asked so nicely!
The pressure equations are written such that there is a sorta smooth transition in an evenly flowing manner, much like a pair of waves.
Look at the pressure equation for an internal combustion engine, and the mean of timing is critical to extracting and converting energy.
So, while my concept of a "Stirling" may be twisted, it still basically is a sealed heat engine, without even fluid state trasition.
The obejct for me then becomes to devise a basic alteration to the standard cyle. The Stirling brothers became famous for the use of the regenerator. Perhaps the modern equivalent is the add-on to the Stirling that converts its intended heat source of constant unusual source, and without too much system cost, pusles it nicely to the timing of the engine cycle.
The less the pressure of the cylinder when the piston is moving { or being moved } into place, and then suddenly on the other side of the top, gets a blast of highest practical pressure, the more the engine will produce power.
The Stirling is unusual in the, if your engine was built to it, could also push as well as pull the power piston. ICE { Internal Combustion Engines } can not do this. The Stirling, given real or delivered wide enough delta of hot and cold could be pushing and pulling at the same time. This is not the curent stat of the Stirling.
The Stirling is like flight, where it was almost a century after the theory of flight was well worked out in theory, before a couple of bicycle repairmen who liked kites worked out practical matters of flight controls and materials.
As to your question? Oh yeah.
One simple "flash system" would be used with a solar heat source. My own design { or maybe first done by others, I don't care } is to use existing trough base, but use fresnal technology instead of transfer to oil in pipe. Duct the super hot solar heat to one end of a commercial Stirling for electrical to hydrogen plant.
As the cylinder goes back and forth, it is tied to a simple apperature open and close, through which the solar blaze may enter, just at the proper timing of the cycle.
Hey, even that is not perfect, and would have many questions, like what magic material will be the side of the engine that passes solar blaze but otherwise is fine.
The idea is that the energy is pulsed.
The flashing could be done by a engine that has the end quick heated or quick cooled by having numerous spikes suddenly thrust into that end, coming from the external means of heating or cooling. Overhead, yes, but leave that to the cleverest engineer. Give him the theory that it would indeed work, if he could make one.
Again, keep at the high level of concept, and pusle the heat delta, will have its own equation of engine power increase for same heat delta.
Does that answer your question?
Regards,
Joe