Posts in tech
Petrol and fire risk: How to avoid blowing yourself up with static electricity

etrol and static electricity don’t mix. Here’s how to keep them apart

Find out how NOT to make a Molotov of yourself at the fuel pumpStatic electricity is the commonest cause of service station fires. This is not because motorists are closet pyromaniacs - it's because many are unwittingly stupid. Most of us underestimate the wickedly destructive potential flowing from the massive amounts of energy locked into conventional liquid fuels

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Precautions for Driving on New Tyres

You’ve just had new tyres fitted, added to the nation’s credit card debt (not to mention your own) via the retailer’s EFTPOS terminal and driven off the forecourt with fresh new rubber.

Feel like testing them out? Maybe right now isn't the ideal time. Here's why:

New tyres are coated in a material called 'mould-release compound', a slippery substance that helps their final extraction from the manufacturing process. It literally helps the new tyres be released from their moulds on the production line. Note that word: ‘slippery’.

New tyres are also kind of furry, you might have noticed, often with flexible rubber ‘stubble’ protruding from the tread face. These little fluffy bits of rubber are called 'vent pips'. They're formed as the rubber flows into little holes in the metal manufacturing dies. They prevent air bubbles from forming in the tread face by allowing all the air (and a little follow-on rubber) to flow out of the dies.

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Are Modern Cars Vulnerable to Hacker Attacks?

The Boeing aircraft company’s new 787 Dreamliner, which is slated for delivery to customers in the airline industry this year, could not fly without some 6.5 million lines of software code that keeps all its avionics and supplementary onboard systems humming along. This incredible amount of software code – a.k.a. computer programming – would take up no less than 197,000 pages of regular, lined A4 paper … if you chose to write it out longhand in your ‘spare’ time. That’s the number of pages in about 1200 copies of a magazine – comprising a stack of really informative dunny reads about eight metres high. That’s a lot of code.

But not compared with a modern, premium class motor vehicle. These have substantially more code – about 100 million lines of it. (Think: stack of magazines stretching 130 metres into the air – enough to plaster the hangers for a squadron of 787s.) So in a sense, your modern vehicle and your home computer network have a lot in common. Only, instead of three computers, a modem, a router, a couple of printers, two iPods and two plug-and-play portable hard drives, a premium vehicle is a lot more complex. In premium vehicles you’re looking at between 70 and 100 networked electronic control units

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techJohn CadoganComment
Things You Probably Don't Know About Engines
  • The big difference between petrol and diesel engines is where the fuel and air mix 
    In the majority of petrol engines liquid petrol is injected into the inlet airstream before it enters the cylinders. A mixture of fuel vapour (droplets of liquid) and air enters the cylinders, where it is compressed and ignited by a spark. A diesel engine ingests only air. This is compressed well beyond the point where a fuel/air mixture would spontaneously burn. At precise points near the peak of each compression event, measured doses of fuel are injected, which ignite spontaneously. The diesel process is more efficient.
  • The piston doesn’t really push spent gasses out past the exhaust valve
    Engines aren’t pumps, but they do experience what engineers call ‘pumping losses’. When the fuel/air mixture burns, it expands rapidly, and this expansion is the harbinger of motive power. It shoves the piston down. Before the piston gets right to the bottom of its stroke the exhaust valve opens. The mixture, still expanding rapidly, is expelled through the aperture of the open exhaust valve. In a very real sense, its expansion pushes it out the chamber. Which leads us to…
  • The piston doesn’t really
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    techJohn CadoganComment
    Freight Factor: Payload-specific Fuel Efficiency

    Traveling one-up in a semi-static sea of cars all headed to or from work in peak-hour traffic is practically a metaphor for envirogeddon. Not only is it the antithesis of enjoyable driving, it’s a profligate waste of energy. Some in the community are quick to point an accusatory finger at motorists, but the real blame in Australia rests with state governments, which have steadfastly, over decades, allowed public-transit infrastructure to grind practically to a halt. In the absence of a viable mass-transit system, there’s … driving. And everyone does it. With the end of oil at least foreseeable, and in the face of rampant global demand, something really should be done.

    Odds-on (unless you endured more than the odd propeller-headed university physics course) you’ve never looked at fuel consumption quite like we’re about to now.

    A great truth about fuel efficiency and consumption is frequently swept under the rug

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    tech, fuelJohn Cadogan Comments