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VGT Variable Geometry Turbo-Chargers

Automakers still developing 2L turbo GDI engines for more than 500 models of cars & SUVS that have not even launched yet. 

Many feature low-lag low- impeller mass VGT or variable geometry turbochargers integrated directly into the engine exhaust header :) 

Many upcoming gasoline vehicles to feature direct injection & new ECU modes that enable HCCI and SCCI enhanced modes of combustion to enable earlier torque through 8-11 speed automatic transmissions to give smoother power delivery ideal for real world daily driving use, while reducing fuel consumption & emissions with variable ignition, variable valves, variable turbo boost, and variable injection.

Continuously Variable Engines

The more combustion variables the ECU can tune on the fly with sensor feedback creates dynamic optimized fuel use that improves power output & performance while reducing pollution emissions, working in concert with newly enhanced exhaust emissions control methods better than catalytic converters called plasma exhaust remediation that uses a high velocity spinning metal conductor rod in the exhaust stream, charged with high voltage to make catalytic gas plasma that breaks toxic exhaust pollutants into non-toxic gases like nitrogen N2 or oxygen O2 that are natural parts of atmospheric air.

VGT Variable Geometry Turbocharger

Exhaust gas exiting an engine exhaust manifold has a lot of thermal expanded exhaust gas heat & pressure with a lot of energy that can be captured by a turbine inside an oil cooled turbocharger when the exhaust turbine blades on attenuated pivots so that a hydraulic, pneumatic or electrical attenuator can adjust the vain angle to vary the amount of energy captured to transfer via the common rail shaft connecting the exhaust turbine to the cold side boost pressure turbine that compresses the air intake of the engine to force air & fuel into the engine under higher pressures to make more power. The boost side of the turbo can also feature variable turbine blade angle attenuation. 

Dual VGT turbos can vary the exhaust & boost turbine blade angles with independent attenuation for even more dynamic power variability so the turbo GDI engine ECU controller has even more options to modulate the way power is made in the engine at different RPM and load conditions. 

Pressurized intake air from turbochargers often channeled through an air or water intercooler to cool the intake air since pressurizing air increases its temperatures and the turbocharger tends to get hot during operation because of thermal loading from the hot exhaust gas. 

Thats why turbochargers typically have engine oil pumped into hydraulic shaft journal or sleeve bearings to separate the cold & hot side & keep the turbo from overheating. An oil cooler a great addition to the turbo oil cooling input to enhance turbocharger cooling to enhance the useful life of the turbocharger, which can cost thousands to replace. 

Early ROTAX GDI

Direct fuel injection engines were originally developed for aircraft use in the 1940's, with early models of ROTAX engines featuring gasoline direct injection. In this aerospace applications where the engine can cost $20K+ its possible to use higher cost technologies earlier in history before mass production low cost optimization possible to achieve. This is why it took until Hyundai group intensively invested in naturally aspirated GDI engine development for gasoline direct injection engines to become mass produced. 

Turbo GDI + Reduced Displacement 

Boosted displacement reduced & direct injection engines are trending because they offer V6 and V8 power output from smaller lighter more fuel-efficient transverse 4-cylinder engines, where the 2-liter engine the most popular because of the magic ratio of bore to stroke that gives 4 swept piston volumes of 500cc, an engineering sweet point where torque & power are optimized vs the amount of metal required to make the block, pistons, and other parts of the engine. 

Energy Density in Vehicle Power Systems

Gasoline 12,000 watt hours per kilogram, while diesel fuel 14,000 watt hours per kilogram. This gives lithium NCA batteries that peak at about 650 watt hours per kilogram a major mass disadvantage, especially since common automotive LIB are more like 200 watt hours per kilogram. Even if the Turbo GDI engine only 35% thermal efficiency, that's still 4000 watt hours per kilogram energy density. In mass sensitive aircraft applications, long range only possible with hydrogen fuel cells systems that offer 2500 watt hours per kilogram or more. 

Battery Electric Aircraft 

Batteries with less than 1000 watt hours per kilogram will limited electric aircraft to low-speed low range smaller low-capacity aircraft, like training aircraft used at regional airports to teach new pilots how to fly. In some cases, higher energy density lithium titanium silicon fluoride batteries will be combined with hydrogen fuel cells to make electricity for electric turbine engines that produce thrust for the aircraft or electric motors to turn propellers fast enough to make good thrust performance. 

Electric Paramotors 

Battery electric backpack fan Paramotors already exist that make use of low mass lithium polymer pouch cells in low mass polymer wrapping to achieve 600 watt hours per kilogram. Flight endurance for battery powered paramotors limited to about 2 hours at 35 MPH or 50KPH speeds. 

Eco-Boost by Ford

Ford got this turbo-charged direct injection engine trend going into mass production with the Eco-Boost engines including that amazing 1L 3 cylinder that has block that can sit on an A4 sheet of paper. This 123 HP small low lag turbo engine was fitted to some Fiesta models with less performance but far better fuel economy via a 5 speed manual transmission. 

Hybrid then Electric

I went with the Honda CRz at the time, with its hybrid IMA & 6sp manual transmission, later traded in for a 2015 Nissan LEAF 30kWh, that then turned into a 2010 Prius III. Our O5 Prius II turned into our 2019 Nissan LEAF SV 40kWh. 

I really love EV instant torque acceleration even though it scrubs off tire tread extra fast sadly. Its the nearly silent face bending instant torque acceleration that makes me smile every time I dive the LEAF :) No oil changes, no transmission, no timing belts or chains, the EV motor sublimely simple with only 1 main moving part & huge, long-life bearings. The Electric Traction Motor in the LEAF SV will probably outlast every other part of that car by 10X or more. 

17 years of Prius II had me longing for an EV as my daily driver. 13 Nissan LEAF S for 24 month lease, $2k at signing & $200 per month, turned in at the end of the lease. 15 Nissan LEAF for 3 years, traded for Megs Prius III her current daily. 05 Prius II sold to Allan for $2k then $20k for 19 Nissan LEAF SV my current daily driver :)

Nissan LEAF SV in "White"  

I use the LEAF SV for commuting to work and back, for trips to Safeway, to random weekend trips locally when it's raining or cold or cold and raining. In the summer our bicycles & motor scooter & motorcycle serve transportation duty to ferry us around. 

A Rove R2-4K dash cam helps keep track of what's happening with digital card records for insurance purposes, also for my YouTube channel here & there if I see something worth uploading. I put a full-size wheel & tire spare in the trunk for additional on the go protection from a full tire blowout event. 

I keep a jack with lug wrench with the spare wheel tire setup to enable change-out on the fly. I put rubber weather resistant floor mats and 2000K golden yellow LED DRL bulbs in the headlamp assemblies that give that good rain & fog penetrating forward illumination that also gives a distinctive visual appearance or style. 

I added a WAGAN seat heater & power outlet splitter high amperage cable adapter so the dashcam & seat heater can share the same 12aux outlet, while also providing an extra USB-A for my short iPhone lighting cable to charge my iPhone 14 for 10-20 min on my way too work. 

I plan to keep this LEAF SV for 3 years or so the see what kind of better EV options are available in 2026 or so. Like Meg's say, you are never stuck in a car, you can always trade it out for something else that better fits your needs or tastes. 

Mid-size SUV and crossovers are trending and popular, like the Tesla Model Y, though other EV's with similar formats & capabilities are available at much lower prices like the Chevy Equinox EV. 

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