Engineering Design is all about solving problems. They can be simple problems or complex problems. Rand Cam Engine falls into the complex category.
Their are many many variables to take into consideraton. The cam geometry is only one of many - But for brevity I will focus on the top five;
1 - Cam & Vane Geometry
2 - Cam Motion
3 - Timing & Control
4 - Engine speed paradox
5 - Theory of Operation
1 & 2 - There are only a few cam motion profiles that can be optimized for the Rand Cam Engine. Once those are selected then it can be applied to the cam part to generate the cam geometry. It is sort of like reverse design in a way. Jim and subsequent engineers apply the geometry first then generate the cam motion. The cams also had 'impact loading' problems because of the cam profile selection.
Even though solving that problem was important I realized that calculating Cam Motion was just as important as calculation of the cams physical parameters. Jim couldn't calculate the cam geometry as an algorithm let alone the cam motion. His original cam was constant velocity. Thus the cam part was easy to calculate.
However when the transitions were added that changed the whole ball game. The sinosoidal term was thrown around quite a bit by layman and engineers alike.
This Cam Motion - Cam/Vane geometry problem is like solving for two unknowns. And one of the unknowns relys on several other unknowns. The most sophisticated super computer on this planet would require to the end of time to calculate a solution.
However the human brain can cut that time requirement considerably as it is the most powerful super computer on this planet. A pity that humans can only use 5 percent of its power.
3 - Timing and Control
This leads into the next problem of timing and control. Jim designed the Rand Cam Engine around the premise of low rpm and he cited lack of back pressure will need better engine braking. He offered no solution to the problem.
One of Jim's sell jobs of his design was to compare a chevy v8 operating at 5,000rpm vs his design operating at 500 rpm. Of course his fuel efficiency is going to be 10 times greater. Hence his promise of 300 miles per gallon.
I am not saying 300 miles per gallon is impossible but how are you going to make an engine that only runs at 500 rpm make enough power? That is where my black box solution comes in. It is going to require very precise timing and control. Only recently has the technology become available from Formula One racing and car racing in general. The combustion process can be measured very very precisely. And once you can measure it - you can control it. But of course who are you going to get to program this black box? :)
4 - Speed Paradox
This leads into the next problem the Speed Paradox. Simply stated an engine needs to run at a certain speed to generate enough power to operate the vehicle. But as the speed requirements increase the fuel efficiency decreases. University of West Virginia and Radian chose to increase rpm to increase power. This completely negated the advantage of the Rand Cam Engine.
So solve the Speed Paradox you need two things - A - Precise Control & B - correct theory of operation.
5 - Theory of Operation
We have Precise Control now we need to revamp theory operation. The patent for Rand Cam Engine states that it is a split cycle rotary engine. However it only splits up two complete cycles on each side of the rotor. The cycles themselves are not split - they are sequenctial. IE intake-compression-power-exhaust.
Much like Scuderi I have truly split the cycles. One rotor for intake and compression and one rotor for power and exhaust.
The result is the intake compression rotor can run at high rpm to generate power. And the power-exhaust rotor can be run at low rpm to save on fuel and extract as much energy out of the expanding gases as possible.
You with me so far?