Talk:Shvetsov ASh-82

ASh-82 used turbocharger?

I can't believe the major variants of ASh-82s used turbochargers. Isn't it confusion between mechanical supercharger and turbocharger? ----Punu (talk) 14:32, 16 January 2009 (UTC)

---

Hello Punu,

Yes,major variants of ASh-82s used turbochargers. The great problem with turbochargers -on the ´30- was its single speed configuration: that means good performance at low altitude only. The critical altitude (where the turbocharger had its best performance) was beetwen 2000 and 3000 meters: over this altitude the engine lost power pretty fast. On the late ’30, new turbocharger types appears: the French invented the Szydlowski-Planiol device (a large single speed turbocharger, much more efficient that all previous boost systems), this improved the critical attitude to 4000 or 6400m on Hispano-Suiza engines, but reduce the performance at low altitude (typical in single speed turbochargers with a high critical altitude). The Americans and Britons used 2 speeds turbochargers to improve low and medium altitude performance, but they wanted to improve high altitude performance too, and developed a two stage system (typically a 2 speeds turbocharger that boost air to an intercooler, and a single speed blower that boost the air from the intercooler to the engine). The supercharger increased the power at all altitudes with a high price: reducing the engine’s TBO (boost pressure was much higher) and reducing the engine’s reliability (About half of the B-29 built during the war were lost, most of them crashed due mechanical failures, engine fires were very common). The Germans had the knowledge to design superchargers, but considered it complicated and unreliable, and fellow a different way to reach similar results: designed very efficient variable speed turbochargers (later models at war reached critical altitudes around 9000m). The Soviets maintain the two speeds turbo, with a not brilliant performance at high altitude (the “Achilles heel” of Soviets fighters). A fighter with an Ash-82 engine had similar to western aircrafts performance below 5000m, but had lower speed over 6000m. That wasn’t a great problem, because the extreme cold temperatures at the Soviet Union skies limited the altitude of the enemy aircrafts (they had a long winter with temps around -60 Celsius over 6000m of altitude…). Nevertheless, the Shvetsov design bureau improved the turbocharger system in the FN and FNU variants: installing two new turbochargers with a better air flow: the critical altitude was lower that previous models (around 5000m), but the engine “retained” more power over the critical altitude. With the FN and FNU engines, the Lavochkin fighters increased the maximum altitude from 8500m to 10500m. In 1950, the Shvetsov design bureau developed an experimental variable speed axial turbocharger for the ASh-4K. This device was comparable to a multiple stage “supercharger” but it wasn't a true one, in any case it dramatically improved high altitude performance: the cruise altitude for these engines was 11000m, and the top altitude was over 12000m (the Tu-4LL testbed arrived to 12000m plenty of power, but cannot exceed this height because it was the aircraft design limit). This axial turbocharger never reached mass-production, because it was complicate to build (needed very precise production techniques and expensive alloys). I’m looking for more information about this device and the Ash-4 at engineering manuals, but my German and Russian language skills are far to be brilliant. ---- Adarech 20:48, 1 February 2009

---

—Preceding unsigned comment added by 85.58.30.68 (talk) 20:53, 1 February 2009 (UTC)

Punu, Poster above is talking about superchargers, so you have to change "turbocharger" to "supercharger" in his/her post. — Preceding unsigned comment added by 62.148.84.70 (talk) 18:30, 10 May 2013 (UTC)

Fw 190 replicas

I notice it says that "most Fw 190 replicas use the Dongan HS-7", which is a license built ASh-82V. Is this because the ASh-82V has a built-in cooling fan, being for use in helicopters? The original BMW 801 had a cooling fan built in, so I'm wondering if they use that variant because it is one of the few engines available with a cooling fan. But then I see that some Fw 190s' use R-2800's, which can't have cooling fans. Maybe they just treat the engines a lot more gently than they did in combat, so they don't overheat? AnnaGoFast (talk) 17:32, 25 March 2016 (UTC)

Weight Contradiction

It says the Shvetsov is a lightened variant óf the Cyclone "This allowed the engine to be used in light aircraft, where an American-design Twin Cyclone, of some 930 kg (2,045 lb) weight in "dry" condition could not be installed." But in the specs it says the Shvetsov dry weight is actually even 100 kg higher than the Cyclone. "Dry weight: 1,020 kg (2,250 lb)" Cancun771 (talk) 22:00, 17 September 2023 (UTC)

The apparent contradiction is due to the engine in the specs section being an 82T, a late development version, the final version, the 82V, weighed 1,100 kg. The first 82 weighed 850 kg which is lighter than the Cyclone. Nimbus (Cumulus nimbus floats by) 08:23, 18 September 2023 (UTC)