Comments by "John Burns" (@johnburns4017) on "The Holy Grail Of Rotary Engines - SkyActiv-X" video.

Rotaries are efficient when burning gas like LPG. Having them burn LPG is ideal for cruise liners having rotaries in banks of generators. Ships are powered by electric motors. If one needs service it is slide out on skids and another slides in, taking 1/2 hour and no down time, which is vital for cruise ships. The service can be onshore. The sunshine ports and the likes of Venice are up against the smoke from diesel engines in the ports.
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🍾▪🩸🥂Announced today. MX-30 R-EV 🍾▪🩸🥂 ..... The innovative 830cc rotary engine acts as a generator for the battery, while the electric motor sends power to the wheels. Combined, the model’s 50-litre fuel tank and battery offer a driving range of over 400 miles, with emissions of 21g/km - a big range increase over the 130 miles provided by the current, EV-only model, which has a 35.5kWh battery. The MX-30 R-EV can travel up to 53 miles on pure electric per charge, Mazda says, which ranks ahead of much larger plug-in hybrids, such as the Suzuki Across, the Toyota RAV4 and the Mercedes-Benz A-Class 250e. It can charge in around 90 minutes using a 7.2kWh charger, 50 minutes on an 11kW unit or 25 minutes with a 36kWh charger.
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Mazda are introducing in Jan 2023 the MX-30 hybrid using a rotary engine for the range extender running at a constant speed.
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As rotaries go, it is not that good. Look at Liquid Piston engines.
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@marshallmonroe884 Jet engine was invented by the British, without doubt. As was the diesel, invented by Akroyd Stuart.
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@marshallmonroe884 There is a myth that the Germans were way ahead of the British in jet engines and planes in WW2, when the opposite is true. The WW2 German jet engines were extremely unreliable with low performances and very high fuel consumption. The German axial-flow turbojets never worked as they wanted being developed up to 1953 by the French to obtain a usable engine. The French lost a lot of time playing around with the German engines, instead of working with the British. The French and Soviets after WW2 tried to improve the German axial-flow engines and largely failed. The Germans did not invent the axial-flow turbojet, they based everything on Frank Whittle's patents. The British Metropolitan-Vickers F.1 axial-flow engine was running on a test bed in 1941. The F.2 was an axial-flow being an extremely advanced design using a nine-stage axial compressor, annular combustor, and a two-stage turbine. It powered a Meteor in November 1943. It was considered unreliable and never saw use during the war, hence why the British went for the reliability, controllability and quick development of the centrifugal turbojets. The Metro-Vick F.3 was the first ever turbofan in 1943. Metro-Vick developed the F.9 Sapphire, however left the jet business in 1947 giving all their designs to Armstrong Siddeley, who commercially produced the Armstrong Siddeley Sapphire engine, which was licence built in the US as the J-65. The British in order to get a usable and reliable jet engine, with the technology of the time, went for a centrifugal design rather than the troublesome axial-flow design. This design produced less thrust than an axial-flow but was quicker to develop and reliable outperforming the best piston engines planes at the time. It took 5 months to develop, while the first reliable axial-flow engine was the 1950 Rolls Royce Avon, which took 5 years to get right. The Avon is still in production as a ground based gas turbine, with the aero version in production for 30 years. In 1945 the French made and tested some German designed turbo jets made with quality steel unavailable to German industry in WW2. They ran for 25 hours instead of the 10 hours of the Germans engines that used poorer quality steel. Not much better. The German axial-flow engines failed because of heavy design flaws. The centrifugal compressor used by the first British Meteor plane was fine and much more reliable, but unable to reach high compression ratios. This limited performances. Centrifugal compressors were used up to the 1960s. In 1945 the team from the French ATAR laboratory plus some BMW and Junkers engineers, were engaged by the French SNECMA research bureau, with the objective to build a new reliable and performing axial-flow turbojet. The BMW 003/Jumo004 was considered unusable. It was tested on the first French jet aircraft, the 1946 So6000 Triton, overheating and exploding. The plane only flew with a Rolls Royce Nene centrifugal turbojet. The ATAR project took 6 years to produce the first acceptable axial-flow turbojet (ATAR 101 B1), produced in 1953. So 8 years research and developments by the French using the German jet engines as the base. It was installed on the first French jet fighter, the Dassault Ouragan. The French lost a lot of time because the German jets had poor efficiency and some concept fails. Essentially in the combustion chambers and fresh air circulation to reduce the external temperature of the engine. The BMW jet was known for overheat problems which precluded fuselage installation. The question at the end of WW2 was: what is the most efficient way to produce jet fighters? The answer was clearly not adopting the German design of engine and fuselage. The build costs for a jet engine were much higher than a piston engine, with the fuel consumption near 3x. The centrifugal compressor the British adopted in some planes was the best choice with 1944-45 technology, more compression pressure was not an advantage when the hot turbine was unable to resist higher temperatures. The German turbojets had big overheat problems as the engine would not work in an enclosed fuselage for single engined fighters. This defect was immediately noted by the French on the 1946 "SO 6000 Triton" prototype, and by the Soviets on the 1946 Mig 9. The Soviets quickly replaced the BMW 004B2 by the centrifugal Rolls Royce Nene which worked without problems, dismissing the BMW engine for fighter planes. The Rolls Royce Nene was copied to the last nut by the USSR being installed in the Mig 15 being used effectively in the Korean war. The Meteor was the first proper fully developed jet plane introduced operationally. The 262 was slightly faster than the Meteor F3, but extremely unreliable. The British would never put into the sky such an undeveloped plane as the me262. The British could have had a jet fighter operational in 1941, but it may have been as bad as the me262. The Germans advanced R&D on jets after they interrogated captured British RAF men. They learned the British were advanced in jet technology and flying prototype planes. Until then the Germans had no intention of mass producing jet planes. The rushed together Me262 started claiming kills on 26 July 1944, the Meteor claimed its first V1 kill a few days later on the 4 August 1944. But the Meteor was a proper fully developed jet plane, not a thrown together desperate effort as the me262 was. The me262 fuselage was similar to a piston plane with the pilot over the wings obscuring downward vision, while the Meteor was a proper new design fuselage specifically for jet fighters with a forward of the wings pilot position giving superior pilot vision, as we see in planes today. The cockpit was very quiet. The sweptback wings of the me262 were to move the engines further back for better weight distribution, not for aerodynamic reasons as is thought the case. The me262's airframe was based on piston engine planes, even with an initial rear tail wheel. The tricycle landing gear was only introduced when it was found the thrust of the jet engines would scorch the runway surface as the exhaust faced downwards. The Meteor's airframe was designed purely for jet propulsion even with a high tail to prevent thrust interfering with the tail which could affect control. Centrifugal compressors were not obsolete being used in turboprops. Between a turbo jet and a turboprop, the only difference is the turbine, not the compressor. The last centrifugal compressor jet engine still in service on a handful of commercial aircraft like the Fokker 27, is the Rolls Royce Dart turboprop. A very reliable engine made in 27 versions, but with high fuel consumption to modern engines. The Rolls Royce Dart Turboprop turbo jet engine was produced the longest, being a comparable design turbojet to the likes the Rolls Royce Nene. The rugged engine was produced from 1946 up to 1987.
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@marshallmonroe884 The 262 was not better. You did not read my post did you?
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@marshallmonroe884 Again, you did not read my post properly!
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@marshallmonroe884 The Me 262 was not designed for jet engines, it first flew in 1941 with a piston engine because the BMW jet engines were not ready. When it was first flown with the jet engines they both failed and luckily the piston engine was still on the plane. When they changed to the Jumo engines they did sweep the wings back a bit, but to only balance the plane. The Meteor was in RAF service from 1944 to 1984, also used by Argentina, Australia, Egypt, France, Israel and Syria. The Meteor set the world air speed record in 1945 and again in 1946 and the London - Copenhagen - London record in 1950 The Meteor also set an endurance record of 12 hours and 3,600 miles being refuelled by a Lancaster tanker in 1949 and several times to height records using Armstrong Siddeley Sapphire engines in 1948. It is still flying today by Martin Baker. No 262 was seriously flying after the Czechs ditched a few after using them for about a year after WW2.
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@marshallmonroe884 A few 262s were flew by the Czechs for a year after WW2. The Soviets gave the plane to them. They had a sort of improved Soviet engine. No one has used one since, with no one ever copying the design.
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@marshallmonroe884 What I wrote was very accurate.
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@marshallmonroe884 ♦ German engineer Ohain did not design a reverse flow engine. His engine had a centrifugal compressor and a radial inflow (centrifugal turbine - a design never used in any production engine - this was a patent filed by Whittle). Ohain even commented on its unusual design when he read Whittle's patent prior to filing his own: From Ohain's biography: "When I saw Whittle’s patent I was almost convinced that it had something to do with boundary layer suction combinations. It had a two-ﬂow, dual entrance flow radial flow compressor that looked monstrous from an engine point of view. Its ﬂow reversal looked to us to be an undesirable thing, but it turned out that it wasn't so bad after all though it gave some minor instability problems." ♦ Whittle's reverse flow design is the basis for almost all turboprop engines in production; ♦ Britain had axial-flow engines running in 1941 - the same time that Franz had his Jumo running. The Metrovick F.2 flew in a Meteor in 1943. The F.2 transpired into the Sapphire which the US built under licence as the J-65 and then modified it as the J-47; ♦ Westinghouse in the US was given a Whittle engine, and plans for improvements. They made such a hash of it that Whittle had to go to the US to assist. The US government gave the project to GE who made the I-16 which transpired into the first US built jet engine. The US licensed the Ghost for the P-80/T-33 and the RR Nene. The Nene was used by the Soviets in the MIG 15; ♦ Ohain's engine was not produced being shelved by 1943. No engine was built using his design; ♦ Whittle also R&D'd axial-flow engines. The metallurgy was not advanced enough at the time. Whittle's engines produced far more thrust than the German axial-flows and far more reliable; ♦ The PT-6, PWC 100/150 are derivatives of Whittle's designs being still produced; ♦ • Whittle's centrifugal-flow engines were built under licence in the US after WW2 - the J-33, J-42 and J-48; • The Olympus was the world's first 2 shaft turbojet and the first to exceed 10,000 pounds of thrust; • The 1950 Avon was the first reliable axial-flow engine. Also the longest produced gas turbine in history being still in production as a land based generator; • The RR Conway was the world's first turbofan; • The RB-211 was the world's first 3 shaft turbofan; • The Rolls Royce Trent was the world's first turboprop to fly; • British axial-flows led the post war world in technology and power; • The axial-flow Sapphire was built in the US as the J-65. The GE J-47 was based on the Sapphire. Frank Whittle invented the modern turbojet.
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Mazda is working with Toyota on a range extender. It "looks" like it will be a rotary for both. Maybe using the Toyota Prius drive on some models as Mazda recently suggested. So a joint venture?
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@sandervanderkammen9230 Doktorbimmer, a quiz. Name the company going to bring out a rotary engined hybrid? 10 points for the correct answer.
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Yes, Mazda are introducing in Jan 2023 the MX-30 hybrid using a rotary engine for the range extender running at a constant speed.
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The cavity in the rotor is uniform in shape. That means the explosion in the combustion chamber acts towards the rotational movement and acts towards the back end of the rotor trying to force it backwards as well, countering the forward movement. This is also in electric motors and known as Back Electro Motive Force. A guy named Ernie Brink said in an experiment he changed the shape of the rotor's cavity so most of the charge is towards the front of the rotor not the back. He said efficiency rose.
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Oh no! Apex seals wearing out That went decades ago.
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Yes, the US military funded it and using it.
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Mazda alone made millions of rotary engines.
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