Not exactly.
Two is multi entry as far as this is concerned. I wrote it that way because I'd mentioned six entry. Anything greater than one is multi entry.PlatinumZealot wrote: β11 Dec 2018, 01:42Not exactly.
The most proven design for six cylinder engines over the decades has been a twin scroll turbocharger. The exhaust pulses are arranged into two groups of three. Dividing the pulses like this keeps the exhaust energy high all the way to the turbine wheel. On the other hand if the pulses were all dumped together in one collector they would "stumble" into each other and waste energy. So with the divided entry (twin scroll) turbo, you get an unobstructed steady pulsing into the turbine wheel. Sometimes the wheel is also "stepped" to match the two scrolls.The benefit is quicker spool and better efficiency.
Twin scroll turbochargers were thought not to be as effective on 4 cylinder engines because the pulses were spaced 90 degrees apart, though to be far enough already... but cars like the Mitsubishi Evolution 8 and Subaru Sti have used twin scroll turbos to great effect.
The opposed entry turbochargers you see in F1 is very similar to a regular twin scroll if you cut a cross section of the turbine housing. Still three cylinders per scroll. The main difference is that the scrolls start and end the opposite sides of the turbine wheel.
And it is not "multi entry" as you said. it is only two entries.
It is the same functionally, still a twin scroll turbocharger. Packaging is just different.hurril wrote: β11 Dec 2018, 10:46Two is multi entry as far as this is concerned. I wrote it that way because I'd mentioned six entry. Anything greater than one is multi entry.PlatinumZealot wrote: β11 Dec 2018, 01:42Not exactly.
The most proven design for six cylinder engines over the decades has been a twin scroll turbocharger. The exhaust pulses are arranged into two groups of three. Dividing the pulses like this keeps the exhaust energy high all the way to the turbine wheel. On the other hand if the pulses were all dumped together in one collector they would "stumble" into each other and waste energy. So with the divided entry (twin scroll) turbo, you get an unobstructed steady pulsing into the turbine wheel. Sometimes the wheel is also "stepped" to match the two scrolls.The benefit is quicker spool and better efficiency.
Twin scroll turbochargers were thought not to be as effective on 4 cylinder engines because the pulses were spaced 90 degrees apart, though to be far enough already... but cars like the Mitsubishi Evolution 8 and Subaru Sti have used twin scroll turbos to great effect.
The opposed entry turbochargers you see in F1 is very similar to a regular twin scroll if you cut a cross section of the turbine housing. Still three cylinders per scroll. The main difference is that the scrolls start and end the opposite sides of the turbine wheel.
And it is not "multi entry" as you said. it is only two entries.
So are you saying that Renault, for instance, ran a twin scroll turbine, but with entry just to one side? See, this is what I'm wondering about: what would be the benefit of doing that?
Right, but why would they change that or go for that in the first place? This is what I'm asking; things don't happen in F1 without a reason.PlatinumZealot wrote: β11 Dec 2018, 16:33It is the same functionally, still a twin scroll turbocharger. Packaging is just different.hurril wrote: β11 Dec 2018, 10:46Two is multi entry as far as this is concerned. I wrote it that way because I'd mentioned six entry. Anything greater than one is multi entry.PlatinumZealot wrote: β11 Dec 2018, 01:42
Not exactly.
The most proven design for six cylinder engines over the decades has been a twin scroll turbocharger. The exhaust pulses are arranged into two groups of three. Dividing the pulses like this keeps the exhaust energy high all the way to the turbine wheel. On the other hand if the pulses were all dumped together in one collector they would "stumble" into each other and waste energy. So with the divided entry (twin scroll) turbo, you get an unobstructed steady pulsing into the turbine wheel. Sometimes the wheel is also "stepped" to match the two scrolls.The benefit is quicker spool and better efficiency.
Twin scroll turbochargers were thought not to be as effective on 4 cylinder engines because the pulses were spaced 90 degrees apart, though to be far enough already... but cars like the Mitsubishi Evolution 8 and Subaru Sti have used twin scroll turbos to great effect.
The opposed entry turbochargers you see in F1 is very similar to a regular twin scroll if you cut a cross section of the turbine housing. Still three cylinders per scroll. The main difference is that the scrolls start and end the opposite sides of the turbine wheel.
And it is not "multi entry" as you said. it is only two entries.
So are you saying that Renault, for instance, ran a twin scroll turbine, but with entry just to one side? See, this is what I'm wondering about: what would be the benefit of doing that?
I think Renault uses opposed entry now though.
I can only surmise that at the time Renault had limited budget/time assigned to engine development and so decided to stick with a conventionally shaped turbine housing to start of with. Notice that in some of their 3D graphic previews before 2014 they had the double sided turbocharger.
1. AFAIK all the teams use a version of TJI. Ferrari specifically had help from Mahle. There is nothing to stop an F1 team using a patented device. A patent only prevents others copying and profiting from your idea.atanatizante wrote: β11 Dec 2018, 11:331. Did Merc implement JTI and HCCI technology or they are exclusive property to Ferrari engine?
2. Which R&D directions are nowadays regarding both the internal combustion engine and PU as a whole?
3. How much gain does worth in % regarding fuel formula? at least this year ...
Had I`m not wrong, there was someone in Merc thread saying he read an article with Andy Cowell telling they had no TJI/HCCI technology with the 2018 internal combustion engine ...gruntguru wrote: β12 Dec 2018, 00:371. AFAIK all the teams use a version of TJI. Ferrari specifically had help from Mahle. There is nothing to stop an F1 team using a patented device. A patent only prevents others copying and profiting from your idea.atanatizante wrote: β11 Dec 2018, 11:331. Did Merc implement JTI and HCCI technology or they are exclusive property to Ferrari engine?
2. Which R&D directions are nowadays regarding both the internal combustion engine and PU as a whole?
3. How much gain does worth in % regarding fuel formula? at least this year ...
Yes about 3 years or so about Andy Cowel was asked if they are using those systems and he said no. but someon on here says these systems are being used.atanatizante wrote: β12 Dec 2018, 01:57Had I`m not wrong, there was someone in Merc thread saying he read an article with Andy Cowell telling they had no TJI/HCCI technology with the 2018 internal combustion engine ...gruntguru wrote: β12 Dec 2018, 00:371. AFAIK all the teams use a version of TJI. Ferrari specifically had help from Mahle. There is nothing to stop an F1 team using a patented device. A patent only prevents others copying and profiting from your idea.atanatizante wrote: β11 Dec 2018, 11:331. Did Merc implement JTI and HCCI technology or they are exclusive property to Ferrari engine?
2. Which R&D directions are nowadays regarding both the internal combustion engine and PU as a whole?
3. How much gain does worth in % regarding fuel formula? at least this year ...
TJI and HCCI are not the same things. Try to not lump them together as such. The rules prohibit the use of TJI as shown in the MAHLE patents however the concept can be made to work with just one injector firing into the main combustion chamber and probably partly into the pre-combustion chamber which is around the spark plug.atanatizante wrote: β12 Dec 2018, 01:57Had I`m not wrong, there was someone in Merc thread saying he read an article with Andy Cowell telling they had no TJI/HCCI technology with the 2018 internal combustion engine ...gruntguru wrote: β12 Dec 2018, 00:371. AFAIK all the teams use a version of TJI. Ferrari specifically had help from Mahle. There is nothing to stop an F1 team using a patented device. A patent only prevents others copying and profiting from your idea.atanatizante wrote: β11 Dec 2018, 11:331. Did Merc implement JTI and HCCI technology or they are exclusive property to Ferrari engine?
2. Which R&D directions are nowadays regarding both the internal combustion engine and PU as a whole?
3. How much gain does worth in % regarding fuel formula? at least this year ...
Thanks SS, It's a good read. Here's a link to the pdf : http://www.idc-online.com/technical_ref ... nology.pdfsaviour stivala wrote: β23 Dec 2018, 11:13Exhaust gasses pulses, even and uneven, single and twin scroll turbine housing a good read βEPI inc-exhaust system technology (the sound and the fury)β. A modified version of an article by Jack Kane which appeared in issue 036 of race engine technology.