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Toysrme, just a couple of comments to your otherwise excellent dissertation:
Roots blowers are called that for a reason. They're positive displacement fans which produce no internal compression. Any rise in compression downstream is due to restrictions on their discharge. This is why they're not called Roots compressors.
Serially connected, or multistage compression is actually very efficient. 90% of all gas compressor stations these days are running multistage centrifugal compressors because centrifugals are a lot like Roots blowers - they can't compress much over 1.5 pressure ratios per stage.
Last time I checked, Mr. Watt's formula was 746 of his little namesakes to the HP, not 749. But shoot, 749 is probably close enough for government work and Nascar.
I think the rest of your stuff is on pretty solid ground; I don't think we'll be seeing any "real" electric turbo's or compressors any time soon, but hey, that doesn't stop the scam artists from building them, nor the morons from buying them off of eBay.
Here's a funny about a guy who managed to acquire an Air Force surplus JATO (Jet Assisted Take Off) unit and strapped it onto his '67 Chebby. This is actually the story that inspired me to write about the gasoline powered weed whacker supercharger. I'll betcha someone here could replicate these results with the Redneck Supercharger, a tad of nitromethane, and a 200 shot of NOS.
The Arizona Highway Patrol were mystified when they came upon a pile of smoldering wreckage embedded in the side of a cliff rising above the road at the apex of a curve. The metal debris resembled the site of an airplane crash, but it turned out to be the vaporized remains of an automobile. The make of the vehicle was unidentifiable at the scene.
The folks in the lab finally figured out what it was, and pieced together the events that led up to its demise.
It seems that a former Air Force sergeant had somehow got hold of a JATO (Jet Assisted Take-Off) unit. JATO units are solid fuel rockets used to give heavy military transport airplanes an extra push for take-off from short airfields.
Dried desert lakebeds are the location of choice for breaking the world ground vehicle speed record. This sergeant apparently took the JATO unit into the Arizona desert and found a long, straight stretch of road. He then strapped the JATO unit to his car, jumped in, accelerated to a high speed, and fired off the rocket.
The facts, as best as could be determined, are as follows:
The operator was driving a 1967 Chevy Impala. He ignited the JATO unit approximately 3.9 miles from the crash site. This was established by the location of a prominently scorched and melted strip of asphalt. The vehicle quickly reached a speed of between 250 and 300 mph and continued at that speed, under full power, for an additional 20-25 seconds. The soon-to-be pilot experienced G-forces usually reserved for dog-fighting F-14 jocks under full afterburners.
The 30 year old Chevy managed to remain on the straight highway for approximately 2.6 miles (15-20 seconds) before the driver applied the brakes, completely melting them, blowing the tires, and leaving thick rubber marks on the road surface. The vehicle then became airborne for an additional 1.3 miles, impacted the cliff face at a height of 125 feet, and left a blackened crater 3 feet deep in the rock.
Most of the driver's remains were not recovered; however, small fragments of bone, teeth, and hair were extracted from the crater, and fingernail and bone shards were removed from a piece of debris believed to be a portion of the steering wheel.
Roots blowers are called that for a reason. They're positive displacement fans which produce no internal compression. Any rise in compression downstream is due to restrictions on their discharge. This is why they're not called Roots compressors.
Serially connected, or multistage compression is actually very efficient. 90% of all gas compressor stations these days are running multistage centrifugal compressors because centrifugals are a lot like Roots blowers - they can't compress much over 1.5 pressure ratios per stage.
Last time I checked, Mr. Watt's formula was 746 of his little namesakes to the HP, not 749. But shoot, 749 is probably close enough for government work and Nascar.
I think the rest of your stuff is on pretty solid ground; I don't think we'll be seeing any "real" electric turbo's or compressors any time soon, but hey, that doesn't stop the scam artists from building them, nor the morons from buying them off of eBay.
Here's a funny about a guy who managed to acquire an Air Force surplus JATO (Jet Assisted Take Off) unit and strapped it onto his '67 Chebby. This is actually the story that inspired me to write about the gasoline powered weed whacker supercharger. I'll betcha someone here could replicate these results with the Redneck Supercharger, a tad of nitromethane, and a 200 shot of NOS.
The Arizona Highway Patrol were mystified when they came upon a pile of smoldering wreckage embedded in the side of a cliff rising above the road at the apex of a curve. The metal debris resembled the site of an airplane crash, but it turned out to be the vaporized remains of an automobile. The make of the vehicle was unidentifiable at the scene.
The folks in the lab finally figured out what it was, and pieced together the events that led up to its demise.
It seems that a former Air Force sergeant had somehow got hold of a JATO (Jet Assisted Take-Off) unit. JATO units are solid fuel rockets used to give heavy military transport airplanes an extra push for take-off from short airfields.
Dried desert lakebeds are the location of choice for breaking the world ground vehicle speed record. This sergeant apparently took the JATO unit into the Arizona desert and found a long, straight stretch of road. He then strapped the JATO unit to his car, jumped in, accelerated to a high speed, and fired off the rocket.
The facts, as best as could be determined, are as follows:
The operator was driving a 1967 Chevy Impala. He ignited the JATO unit approximately 3.9 miles from the crash site. This was established by the location of a prominently scorched and melted strip of asphalt. The vehicle quickly reached a speed of between 250 and 300 mph and continued at that speed, under full power, for an additional 20-25 seconds. The soon-to-be pilot experienced G-forces usually reserved for dog-fighting F-14 jocks under full afterburners.
The 30 year old Chevy managed to remain on the straight highway for approximately 2.6 miles (15-20 seconds) before the driver applied the brakes, completely melting them, blowing the tires, and leaving thick rubber marks on the road surface. The vehicle then became airborne for an additional 1.3 miles, impacted the cliff face at a height of 125 feet, and left a blackened crater 3 feet deep in the rock.
Most of the driver's remains were not recovered; however, small fragments of bone, teeth, and hair were extracted from the crater, and fingernail and bone shards were removed from a piece of debris believed to be a portion of the steering wheel.
Ironically a still-legible bumper sticker was found, reading:
"How do you like my driving? Dial 1-800-EAT-SH*T."
1995 Darwin Award Winner
"How do you like my driving? Dial 1-800-EAT-SH*T."
1995 Darwin Award Winner
Battery packs (Like from R/C) are the only really good way to power one.
