Rarinn's Ideas

My previous posts assumed that two-stroke construction based on Lenoir cycle will be used. Charge would be admitted at higher pressure, and admission would take place only at the beginning of downward stroke, then fuel-oxidizer mixture would be ignited by multiple spark gaps, and power extraction would begin. Various combinations of ammonia, hydrogen, air, and oxygen could be used. After researching multiple options, I came to the conclusion, that burning NH3 with air is the best bet for a land vehicle that is expected to have reasonable range. Separating O2 from air (or H2 from NH3) would require bulky counterflow heat exchangers, that would accumulate H2O and CO2 on their surfaces. I was thinking about marketing it as negative-emissions vehicle, but it probably would be a bad idea, nevertheless it could be possible to have heat exchangers connected in parallel, so when one of them clogs, another one acts as a bypass, and can continue to change temperature of passing gases. Four-s...

I wanted to share some of my observations concerning physical limits of photographic equipment. Decades ago 35 mm film was common, and now most photographs are made with slim pocket devices. Dedicated cameras are available, but actually not many people that I know own them (I certainly don’t). It means that popular cheap cameras produced in USSR used film with image size of 36 × 24 mm (864 mm²), while modern marvels of engineering from capitalist China sport image sensors that rarely have bigger size than 8 × 6 mm (48 mm²). Modern digital sensor have better sensitivity and resolution than ancient film made from dead animals (gelatin is an essential ingredient), so some of the problems with small frame size are alleviated. Depth of field, as I will latter show, depends only on the diameter of entrance pupil (for a given angle of view), so having a bigger camera does not mean that range of of distance at which objects can still be sharp is extended. But if reduced depth of field due to...