Autoholics965 Special: Rotary Versus Pistons

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So you’ve probably been hearing about the Rotary engine for a while (Maybe not so much if you’re living in Kuwait). Well, if you’re wondering what a Rotary engine is exactly, and what’s the difference between the engine and the piston engine, well you’ve come to the right place. We’re going to break it all down to you.

Well, the Rotary engine is basically an internal combustion engine, basically the same one in your car. Everything back from the flywheel is pretty much the same, however infront of the flywheel, that’s where everything changes. The Rotary engine works and looks in a completely different way than your typical piston engine.

If you’re familiar with basic mechanics, you’d know that the standard piston engine uses a crankshaft and the connecting rods to convert the upwards and downwards motion of the pistons to rotary motion to power your vehicle. In the rotary engine the pressure is controlled in a small space by a part of the housing and sealed by a triangular rotor (imagine a spinning dorito, it pretty much looks like that). Which is what the rotary engine uses instead of pistons.

So for demonstration purposes, this is how your engine works:

With it’s 4 stroke cycle: Intake, Compression, Power and Exhaust.

And here’s how a Rotary engine works:

The triangular rotor follows a specific patter which keeps the peak of the triangular motor within contact of the housing, which engineered in such a way that the peaks of the triangular motor will always be in contact with the walls of the chamber. Each part of the housing is dedicated to one part of the combustion process.

The triangular rotor has peaks. Those “peaks” basically act like a piston. Since the rotor has three sides, those sides have pockets which increase the displacement of the engine to allow more increase of space for the air/fuel mixture.

As the rotor moves around, each volume of the gas in turn expands and contracts, which draws air and fuel into the engine, compresses it, and BAM! Power. After that, the exhaust is then that expelled.

DERE

Here’s how the combustion process works in the engine:

1) Intake: Fuel/Air mixture is drawn in the intake port. (Notice the one of the main differences between the two engines: There are no valves in the Rotary engine, instead it uses intake and exhaust ports which are directly connected to the exhaust and throttle respectively.)

wankel_in

2) Compression:- Mixture compressed in the yellow part

wankel_cmp

3) Power/Combustion: Mixture burns, driving the rotor.

wankel_pwr

4) Exhaust: Exhaust is expelled:

wankel_exh

The rotary motion is then transferred to the drive shaft by the eccentric wheel (Above, in blue). The drive shaft rotates once during every power stroke instead of twice.

Since we got the basics out of the way (and I don’t want to get into too much details here), I’m going to come right down to the battle. PISTONS OR ROTARY?

If we go down to the simplest 4 cylinder engine, it would have ATLEAST 40 moving parts, including your pistons, connecting rods, camshaft, valves, rockers, timing belt, timing gear, crankshaft etc. and you have more with the increasing cylinder counts once you move into V8, V10, V12 configurations etc.)  A two rotor engine has 3 moving parts (2 rotors and the eccentric shaft). This makes the rotary engine smoother, lighter, and produces higher RPMs. Your piston engine has to convert reciprocating motion into rotational motion and by doing so the pistons violently change directions. Rotary engine spin in one direction, and as a result are a lot more smoother.

One of the most important factors to put into consideration is that rotary engine are pretty much immune to total catastrophic failure. A rotary engine that loses compression, cooling or oil pressure will lose a large amount of power, but the engine is still able to produce power and operate. Piston engines under similar circumstances are prone to seizing or breaking parts that will result in major damage of internal engine parts resulting in an instant loss of power and operation.

Since it’s all good and dandy, here’s the bad sides:-

In a piston engine, the cylinder and piston have a rather large contact surface which is constantly lubricated and seals the combustion chamber against the crank case. In a rotary engine, the tips of the triangular rotor drive along the chamber walls to seperate the chambers. This means they have to be very precisely positioned and bear a lot of load, compared to a regular cylinder lining. The tips have to be extremely abrasion resistant and hard, but function as tight seals as well. That’s a difficult trick to pull of and makes the whole system somewhat less reliable. Also, a rotary engine will consume as much fuel as a V6, which gives it terrible gas mileage.

Also, the rotary engine is owned by Mazda. It’s design, improvements, and basically everything is owned by Mazda. You have thousands of companies in the world continuously working on improving the piston engine. With the rotary engine you have one company, which is Mazda, that’s actively restricting the ability of other companies to invest in it’s engine. Long story short, if you have 10 people working on one idea and 10,000 on another, you’re going to work more with latter idea. The piston engine is better-understood and its improvements are more accessible, someone working on a new engine improvement is more likely to start from that point than they are from a Rotary Engine point.

The average life span for a rotary engine is also normally less than that of a piston engine.

So, since you have all of that? Which would you chose? Rotary or Pistons?

Well, I’d personally go with my biased opinion.I prefer my engine Piston-runned. Viva La Pistons!

If you want to read/see more of the Rotary Engine:

http://www.nationalspeedinc.com/gear-and-tech/advantages-and-disadvantages-of-a-rotary-engine/

http://auto.howstuffworks.com/rotary-engine.htm

http://en.wikipedia.org/wiki/Wankel_engine

http://www.autoblog.com/2012/07/27/this-is-what-a-six-rotor-wankel-looks-and-sounds-like/

http://www.youtube.com/watch?v=6BCgl2uumlI

http://www.youtube.com/watch?v=lyItjvs8nvI

http://www.youtube.com/watch?v=ocZ0veZjiBs

 

F1 Friday: Mika Hakkinen

ImageThere’s no doubt that Finland produced some of the greatest F1 Drivers. From Keke Rosberg who was the first Fin to take World Drivers’ Championship in 1982 to the current competitor Kimi Raikkonen who won the WDC in 2007. However, we will get to those crazy Fins sometime later. 

Today I picked Mika Hakkinen as the for our F1 Friday driver. Besides being totally cool on the outside, he remains on the most consistent drivers on F1, ever. 

Born on the 28th of September 1968 in Vantaa, Finland. Mika started out his driving adventures young, as he first got on the track at the age of 5 years old on a local track. However, things weren’t really fortunate for him as he managed to get into an accident on his first lap. However, despite the accident, he kept on persisting that he wanted to continue racing. And so, his adventures began after he recieved his first go-kart

Hakkinen was already begging to climb the ladder of fame by 1986, as he had won five karting championships. Dubbed the Flying Finn by the Scandinavian Media, he won 3 Scandinavian Championships and the Opel Lotus Euroseries Championship in 1988 before finally winning the 1990 British F3 Championships. It was also in 1990 that he the notable encounter with the infamous German, Michael Schumacher. In the Macau GP, he was running second place behind Schumacher, as he tried to pass him, they both touched, and that resulted in Hakkinen being put of the race.

However that was only determination for the Flying Finn, as he made his F1 debut with Lotus the following year. He started out with a very strong preformance in the Phoenix Grand Prix before he struggled with engine failure. He continued on the season finishing at joint 15th position. However the season wasn’t as he hoped it would be as he was plagued with mechanical issues. The following season was pretty similiar, which resulted in Hakkinen retiring from more than 1/3 of his races, which eventually lead to his switch to McLaren in 1993.

 

After the switch and having to have had prove himself to step up from being the test driver, he out-qualified his team mate Ayrton Senna in his debut in Portugal, who was by that time a 3 time world championship. After Ayrton leaving McLaren for Williams, Mika had become lead driver for Team McLaren.

In 1995, he had a disastrous crash at the practice in the Australian GP, having had a tyre failure in the first qualifying session. Which led to him heavily crashing in the walls of the circuit. The crash resulted in him having a skull fracture, heavy internal bleeding, and the impact of the crash lead to him swallowing his tongue, and his life was saved by an emergency tracheotomy (fancy word for having your throat cut and having a tube inserted to help you breathe). Despite the serious injuries he sustained, he made a full recovery and returned to the after track 87 days. He got back on his ’95 McLaren MP4/10 in the Le Castellet circuit in France.

 He continued proving himself and growing stronger on the track and it all game together in 1998. He have won the 1998 season opener in the Australian GP and he continued battling Michael Schumacher to finally push him off the edge and being led to be crowned World Champion in the final round in the Japanese Grand Prix. In 1999, his season was a success as he managed to maintain his World Championship title, being the first Fin to ever win back-to-back titles. 

After his successful runs, he began to decline in performance, until he finally left the sport in 2001.

Some Quotes:

“I’ve been through so much in my career in F1, particularly in 1995, and I did achieve so much that I thought it’s not worth it any more to push your luck further.”

“Formula One is a mind game, no question. You have to think so hard sometimes smoke comes out your ears! And if you don’t keep your head in gear the car will overtake you”

 

Some videos on Mika: 

http://www.youtube.com/watch?v=QNCXOznFI_8

http://www.youtube.com/watch?v=-8j6JLlLKNA

 

 

 

 

Offroading/Mudding (Sort-Of) Near Julia'a

I tagged along with a GMC Sierra 1500 with my ’06 Nissan Titan for a bit of offroading. We drove around King Fahad Highway until we found a good spot to get our trucks dirty. It was nearby Julia just before what I think is a military base (Could be mistaken). Our main objective was to go out for some photography, so we did not want to get far. It’s just a desert with a bunch of people setting up their camps and there is some space before the camps to start mudding around and snap a couple of pictures. Although there are better places to go around mudding and offroading and such, we decided it would be good to stay nearby the highway in case we get stuck or in trouble. It was raining the day before so the ground was pretty muddy. Exactly what we needed! We took a decent number of pictures before we headed back, and here’s some pictures from the trip for your viewing:  

 

 

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The Aftermath: (Cost me 15 K.D just clean my truck from it’s mess!)

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