| Abstract | Ideja konstruiranja i razvoja šesterotaktnih motora iako nije nova, tek je sada došla do
izražaja zbog raznih restrikcija koje se postavljaju na motore s unutarnjim izgaranjem u cilju
smanjenja emisija štetnih plinova. Iako su današnji četverotaktni motori u odnosnu na prošlost
znatno efikasniji i emitiraju manje štetnih plinova, još uvijek nisu zadovoljavajući za budućnost
te se teži potpunoj elektrifikaciji. Porsche je u suradnji sa Tehničkim fakultetom Cluj-Napoca
konstruirao ovaj motor kao jedan od mnogih pokušaja autoindustrije i njezinih inovatora da
prolongira život i korištenje motora s unutarnjim izgaranjem. Iako se na prvu čini da se radi o
kompliciranoj i novoj tehnologiji koja zahtijeva puno istraživanja, situacija nije takva, naime
šesterotaktni motor funkcionira i zasniva se na 100 % konvencionalnoj tehnologiji koja je
dostupna i koristi se već desetljećima te je samim time i pouzdana. Šesterotaktni motor
kombinira karakteristike četverotaktnog i dvotaktnog motora na jedinstven način kako bi
poboljšao učinkovitost, smanjio emisije i optimizirao performanse. To ostvaruje dodavanjem
još jednog radnog takta što omogućava ponovnu iskorištenost energije iz prethodnog ciklusa,
samim time podsjeća na učinkovitost dvotaktnog principa, ovim dodatnim procesima smanjuje
se količina neizgorjelog goriva i povećava ukupnu iskoristivost energije, čime se postiže veća
učinkovitost nego kod dvotaktnih ili četverotaktnih motora samostalno. Ono zanimljivo kod
ovog procesa je što u teoretskom razmatranju šesterotaktni motor nudi 33% veću snagu za isti
radni volumen i brzinu vrtnje.
Ovaj rad fokusirati će se na upravo taj patent Porsche-a u suradnji sa Technical
university Cluj-Napoca, gdje će se detaljno opisati rad ovakvog motora, njegove prednosti i
nedostatci. Izrađen je 3D CAD model klipnog mehanizma iz kojega je za proizvoljni kut zakreta
koljenastog vratila moguće odrediti pomak klipa u odnosu na minimalnu gornju mrtvu točku,
taj CAD model uspoređen je sa analitičkim rješenjem za pomak klipa. Izvedena je krivulja
indiciranog momenta te je uspoređena sa istom za četverotaktni proces. |
| Abstract (english) | The idea of designing and developing six-stroke engines, though not new, has only
recently gained prominence due to the various restrictions imposed on internal combustion
engines to reduce harmful emissions. While modern four-stroke engines are significantly more
efficient and emit fewer harmful gases compared to those in the past, they still do not meet
future requirements, pushing the industry toward full electrification. Porsche, in collaboration
with the Technical University of Cluj-Napoca, has designed this engine as one of the many
attempts by the automotive industry and its innovators to extend the lifespan and utility of
internal combustion engines. Although at first glance this may seem like a complex and novel
technology requiring extensive research, the situation is quite different. The six-stroke engine
operates and is based entirely on conventional technology that has been available and in use for
decades, making it inherently reliable. This engine uniquely combines the characteristics of
four-stroke and two-stroke engines to improve efficiency, reduce emissions, and optimize
performance. This is achieved by adding an additional power stroke, allowing energy from the
previous cycle to be reused. In this way, it mimics the efficiency of the two-stroke principle.
These additional processes reduce the amount of unburned fuel and increase overall energy
utilization, resulting in greater efficiency compared to standalone two-stroke or four-stroke
engines. What is particularly interesting about this process is that, in theoretical analysis, the
six-stroke engine offers 33% more power for the same displacement and rotational speed.
This paper focuses on the Porsche patent developed in collaboration with the Technical
University of Cluj-Napoca, providing a detailed description of the operation of such an engine,
its advantages, and its drawbacks. A 3D CAD model of the piston mechanism has been created,
enabling the determination of piston displacement relative to the top dead center for any given
crankshaft angle. This CAD model has been compared to the analytical solution for piston
displacement. A curve of the indicated torque has been derived and compared with that of the
four-stroke process. |
