What Fusion Power means to the Project

[tsofian]

A quick look says electric motors are really massive

[ChalkLine]

Yep, it's a trade off. It's also a good, mature technology though.

How widespread are these fusion reactors just before the apocalypse? Really, keeping them purely for after-disaster teams just to retain an edge is a terrible crime

[mmartin798]

For comparison, let's just replace the Cat C15 diesel in the HEMTT A4 with a 500HP BALDOR 3PH Motor. Both generate 500HP, the C15 at about 2000 RPM and the BALDOR at 3600 RPM. The C15 engine without any of the exhaust treatment gear attached is 49in tall and 57 in long. The BALDOR is 40in tall and 67in long. The C15 dry weight tips the scales at roughly 3500 lbs, the BALDOR has a shipping weight (couldn't find the comparable dry weight) of 4780 lbs. So it is about a half ton heavier and almost a foot longer, but you gain a lot of head space.

[Gelrir]

An electric vehicle doesn't need the same horsepower as an internal combustion engine for the same performance; in some modern high-performance electric cars, they get by with about half the rated horsepower of an internal combustion-engined car.

For example:

https://youtu.be/6YuTpPr3Uv0

and:

https://auto.howstuffworks.com/how-d...ctric-cars.htm

"Remember, the Tesla Roadster S is about as fast as a Corvette Z06 with almost half its horsepower."

So I don't think the correct "conversion" (for identical performance) is to swap in an electric motor of the same horsepower.

--
Michael B.

[nuke11]

You should be researching in-hub electric drive motors. These are the current trend in hybrid electric wheeled AFV's. They have also been tested for tracked vehicles as well.

They replace a standard AFV wheel hub. They are based on a 100kW continuous traction motor with a liquid cooled brake inside the hub.

Also from about 8 years ago the E-Drive Stryker is a good research project as well.

[mmartin798]

Felt obligated to do the math and stuck with the HEMTT A4, since I have all the specs I need for the calculations. Looking at maximum torque at the wheels; taking into account the engine torque, transmission and transfer case gear ratios; we get a total torque at the wheels of 15 252 Nm or 1906 Nm per wheel, since you can just divide it if you are assuming straight line thrust.

Looking at some Moog DB-22000 series motors, this puts us right in the middle of the pack. If we go with a DB-22000-E at each wheel, we get 2539 Nm of torque in a package that is 181 lbs and measures 5" in diameter and is 5.15" long. Since this is a frameless motor, we can add about another 5" or so for the frame, cooling system and other monitoring and diagnostic components and still fit inside the 17" rim with room to spare. If we assume the mass of each motor goes up to 250 lbs each, we only top out at 2000 lbs, which is about 1000 lbs less than the diesel it would replace.

Since the HEMTT A4 has the same performance specs, twice the axels and twice the mass of a V-150, the motors for a V-150 would probably be the same size with a proportional weight savings.

[nuke11]

I'm under 2 lines of thought for fusion conversion of a vehicle at the moment, leaning towards option I.

Option I conversion: simply take out the internal combustion engine and add fusion power source, electric motor and conversion plate to the existing transmission and drive train. Quick and simple conversion that does not require major alterations to the vehicle.

Option II conversion: this one is based on in-hub electric drive motors at all wheels. Take out the internal combustion engine, transmission and most of the drive train. Modify the wheel hubs and suspension.

Note: "Fusion power source' would include inverter(s), possible storage batteries.