whos got the most far fetched idea?

[multispool]

Hi Zippalot,

I understand what your trying to say, and yes it's the residual energy left over that provides thrust in gas turbine engines. If I may explain the process, there is no thrust as such before the thust nozzle, the turbin wheel absorbs heat enery from the gas flow ( in our small engines this is in the region of about 150-200k temp differential across the wheel. This energy is used to drive the compressor. Most small engines with single stage centrigugal compressors have a typical compression ratio of around 2-1. The secret to a good design is to achieve the best pressure recovery possible, this is a very difficult task with our diffusers with such short passage lengths.

Someone once told me that a steam engine is 3-6% efficient!

[Zippiot]

the higher the compression the higher the power (in pistons engines of equal size and design). is it much easer to make a turbine with only one compression wheel? is that why it took so long for countries to create those long turbine (all plane turbines are every long i noticed). this must be due to many compression wheels correct?

howstuffworks.com said that the some of the wheels are stationary while others spin under power from the shaft. my question is this, from all that compression the combustion chamber must be considerably smaller than the intake, or the inake must grab buttloads of air. if it grabs so much air, then at what speed is it inefficient?
only the new military jet planes have hypercruise (or so the disc channel has told me) which is where they can cruise above mach1 without an afterburner. but i have seen many jets that reach well into mach3, if they cant cruise at that speed then isnt that a huge inefficiency?


plus whenever i see turbine powered dragsters the announcer says they r the most efficient, but then he explains that they used 7 gallons of fuel per second!!

[marksteamnz]

Someone once told me that a steam engine is 3-6% efficient![/quote]

Depends on the size coal fired steam power plants run over 40% efficiency fuel to shaft horsepower Combined cycle plants are close to 60%

[multispool]

The multi stage axial compressors are for high compression ratio and small frontal area. High CR and high temps are good for efficiency but difficult to obtain with our engines because simplicity must over-rule and also need to work within the capacity of the materials used.
Gas turbine are designed to work at one speed, this is where they are the most efficient.

The combustion chambers can be any size within reason athough the smaller they are, the harder it is to make them work. The mass flow through the engine remains constant so what comes in the intake has to go through the chamber.

[Zippiot]

anybody else hear about the new ignition systems for cars?

microwaves!!

it creates some kind of plasma that can be turned on or off faster than a spark from a spark plug. also it creates more heat and a larger area of heat, burning the fuel more completely. and is gone in an instant once the power to the new microwave plug is turned off.

metal+microwaves=good?

[Zippiot]

can a flying wing be controlled by canards successfully?

i am trying to modify my r/c airplane because it is too hard to handle at the moment, i feel it is because the flaps are freaking huge and right on the back of the plane. i was thinking about adding a small triangle of glassed foam to the front of it, and moving the flaps to that. it will be quite simple to control them because the servos are in the middle of the plane, all i need to do is attach the rod to the front and not the back.

[Najm]

metal+microwaves=good?

I dont know if they are good but nothing bad happens
Mythbusters tried it and their microwave didnt explode although the metal spoon got very hot.

[Zippiot]

i have broken quite a few microwaves with metal. you can tell when they brake, they start to smell like ozone...

cut a grape in half, but leave the skin attached. fold the grape so that the juices face upwards, make sure the skin is still attached!! after about 2 or 3 second sin the microwaves, the grape will ark and catch fire.

if you have a microwave that you are willing to risk destroying i have many many more fun things to do in them

[Jonny69]

Apparently pickled onions light up in the microwave. True or myth?

[Zippiot]

if properly prepared true. if you just throw one in there it wont light.

anything with lots of salt in it will light, even saltwater itself. get a microwave safe shallow narrow cup that you dont much care for. fill it 3/4 with salty salty water, as much salt as you can dissolve in it. as soon as it starts to boiil over you will see arching and fires break out.

no clue as to how or why it works.

also, i know i said it above, but does anyone know if an r/c flying wing can be controlled by canards? usually if people dont respond it is because they dont have an answer, but in a long thread like this things tend to get covered up

[El-Kablooey]

i have broken quite a few microwaves with metal. you can tell when they brake, they start to smell like ozone...

cut a grape in half, but leave the skin attached. fold the grape so that the juices face upwards, make sure the skin is still attached!! after about 2 or 3 second sin the microwaves, the grape will ark and catch fire.

if you have a microwave that you are willing to risk destroying i have many many more fun things to do in them

Here's a fun one, put old cd-roms in your microwave and watch the ball lightning show.

[Zippiot]

yeah, i showed that one to a kid at school, i used a really old mic for 3 seconds. he thought it was cool so he tried it, and the microwave broke. he told on me (the little bastard!!) and i had to pay for 1/2 new microwave. turns out he left the cd in there for 10 mins and walked away............................god was i pissed

26 bux and i didnt even brake the thing, the little kid did.

i am for sure launching something in his direction.

dont play around with metal in the microwave unless you are willing to replace it...

[Hank]

Far fetched? Take that thought and give it the intense workout it so thoroughly deserves at:

http://solidedgecommunity.com/news_full ... 2&id=73035

This years competition in paper.

[Zippiot]

how to shred papaer in 20 steps? i will make a steam engine, that will power a bunch of gears, which will eventually spin up a turbine until it starts that will melt through a rope that will drop a hammer on an electrically sensitive switch, completeing a circuit that engages a pneumatic cannon. which will shoot a hole through a board, allowing a ball to roll through. the ball will run a course where it turns on multiple switches, each switch lets an elevator move down just slightly, until it reaches the ground floor. this spills potato chips on the floor, and a roomba will come clean it up. the roombas base has a pressure senstivie scale, and with the added weight of the chips it sets off an array of rockets. each rocket has a target, and only one needs to hit it in order to activate the giant blade. the blade spins up when a rocket completes the circuit, then the blade slowly pulls papaer towards it and shreds it, but befor eit does that the blade cuts through the wooded box containing the paper.

15 steps good god this is harder than it looks!!!!!!

[Anders Troberg]

Metal is OK in a micro wave as long as it doesn't have short gaps (lika a fork). The waves just reflect off metal. The problem appears when you have only metal and no other material to absorb the energy.

I frequently leave the spoon in when I make powder soup in a cup, as this allows bubbles to form on the spoon which lessens the chance of superheating the water.

My old micro wave even said in the manual that it was OK to heat food in tin cans, as long as they were opened and full, but it may shorten the life span of the oven slightly.

One fun experiment if you have an old micro wave is to put a small burning stick in it and blast it with micro waves. Makes nice plasma balls.

I've always wanted to try to seal a micro wave oven, then fill it with a suitable inert gas, like neon. It would be interesting to see what would happen and what it would look like.