Fuel Definition and 563 Threads

Will switching to alloy wheels (typically 17% lighter than steel) noticibly improve fuel economy? It seems like we should be able to calculate a rough estimate if we had necessary data but i don't. Has anyone been there?

For weeks after the Chernobyl disaster, many tonnes worth of molten "lava-like" nuclear fuel inside Chernobyl's shattered reactor vault eventually cooled down and formed into a hardened substance similar to ceramic. When nuclear fuel overheats and melts, how long does it remain in it's...

Could one really big hydrogen fuel cell battery replace a nuclear reactor in providing power to millions of people? This may end up being a safer option for generating power.

What I mean by the title is, why isn't it more popular? (I know there DO exist some hydrogen powered cars.) To me it just makes sense to use hydrogen. It is very explosive and it's byproduct is water! The only draw back I can see is storing the gas in the vehicle to be used. Can anyone...

Saw this for sale at Best Buy: http://reviews.bestbuy.com/3545/9754101/fuel-doctor-fuel-efficiency-booster-gray-reviews/reviews.htm The claim is that via power conditioning, the device improves the accuracy of your car's sensors and other electronic devices, thereby improving the car's...

Hi all. I need help on an issue I can't figure out. What is the difference between 15x15 and 17x17 fuel when it comes to moderation properties? Standard fuel with these lattices have dimensions 15x15: pitch: 14.3 mm, d_rod: 10.77 mm 17x17: pitch: 12.6 mm, d_rod: 9.5 mm These geometries...

Hello and here is my problematic 1st post. I have a problem which i need help with, I'm an electrical engineer so my understanding on this subject is basic. I need to calculate the cooling effect of a AGR fuel pin and I'm not sure were to start. Here is some background on the question...

I am just a finance guy, but I've been reading up on the current crisis and found this blog. Anyone here thing this guy might actually be correct in his assumptions? http://atomicinsights.blogspot.com/2011/03/focus-on-food-water-shelter-dr-greg.html

Could anyone who actually works on this kind of thing answer a couple of questions about the current situation in Japans nuclear crisis : Is it true that cooling pools for spent fuel rods are stored on the rooves of these reactors ? If so we see two of these rooves have been blown off - so...

Homework Statement Why does a car uses more fuel with lesser air in tyres? Homework Equations Work done =F.d The Attempt at a Solution According to me Friction does no work in rolling if the tyre is purely circular. But when tyes are deflated then they are not circular. Due to...

If my car goes twice the distance on the same amount of fuel, doing twice the distance the friction and wind resistance is double. Can I say my engine uses fuel 4 times more efficiently? Or is it only double? My thinking behind it comes from Ohms law, if you double the voltage you get 4...

I've posted on here in relation to an aerospace analysis project I'm doing. I'm stuck on one part of the project where I need to develop the performance envelope of the turbojet engine. 3 of the 9 plots that are required are Thrust vs. Mach number. On each of those plots I'll about 7 different...

Do exist some proposed nuclear fuel cycle in which uranium or thorium whoud be first converted in some beta or alpha emitting isotope and after energy whould be harnessed with direct energy conversion methods?Possibly, it could reduce size of power plant and make steam turbine unnecessary.

A spacecraft ’s motors provide a total thrust of 1.5 MN. If the exhaust speed is 2.5 km/s, at what rate is fuel being used?Homework Statement Thrust = 1.5 MN Exhaust speed = 2.5 km/s rate fuel being used = ?

Hi, Could someone explain what is a motive flow in the aircraft fuel system? Thanks, Suresh

"A rule of thumb is that for every ten-percent increase in efficiency for rocket fuel, the payload of the rocket can double.” Can someone assist me with a simple formula to model this rule-of-thumb? What happens to the payload if the rocket fuel efficiency increases twenty to thirty percent?

Low Temperature Diesel Fuel (urgent) I'm having a problem with diesel fuel at the moment and would greatly appreciate insight into the subject. I'm currently stranded in Colorado where it's somewhere like -10 degrees (F) and our diesel truck isn't starting. I've narrowed down the problem to...

Homework Statement Hello, I am currently a gr 12 high school student, and I am stuck in a problem. Please help :) The problem: Consider the motion of a rocket near the surface of the Earth. In this case, mass, in the form of gas is expelled from the rocket to propel the rocket upwards. A...

if fuel coposition as follow : 75 wt% Tho2- 25 wt% uo2, were the U enrichment 19.5 w% ... how can i caculate the number density (Atoms/barn-cm) for the comopsition ?

Imagine this scenario: An "airplane" that runs on some type of fuel, let's say, liquid, reaches 90% of the speed of light. Once it achieves this speed, will the ship require less fuel due to time dilation, the same amount of fuel due to time dilation, or more fuel to maintain a constant...

1- i have a proplem to understand the meaning of the once & twice burned fuel, and why we use when we going to simulate the whole core 2- is there a specific formula for the IFBA radius,

Hello all - once again! I am an aspiring SF writer currently in the process of writing a book. I am looking for ideas (go nuts!) for different types of spaceship fuels. The idea is that the fuel has to be something that exists in abundance (preferably naturally occurring), and...

Homework Statement A rocket rises vertically, from rest, with an acceleration of 4.0 until it runs out of fuel at an altitude of 1500 . After this point, its acceleration is that of gravity, downward. How long does it take to reach this point? What maximum altitude does the rocket...

Basically as the title says, is it possible to build a DB fuel cell stack? Something that could output 100W (to power a laptop or for power outages). I actually have access to a couple of kilos of sodium borohydride and while looking at what I can do with the stuff I came across this type of...

Greetings everyone! Just a few weeks ago, I got it in my head that I'd like to determine some formulas for the efficiency of an engine - particularly mine, a 1991 Geo Metro. The overall goal is to compare various acceleration rates to show how slower acceleration can produce greater gas...

Homework Statement Finding the volume of a partially full cylindrical tank that lies on it's length. L=6', D=4" Homework Equations pi r sq times L = cu ft when full. Convert to gallons 1 gal. = .1336 cu. ft. (I think) The Attempt at a Solution (pi r sq times L)/2 =...

Investigate the potential for the use of a nuclear fuel source for aircraft propulsion: If anybody have related document and ideas please post it

I've been to Crappy Tire and I've been to Fogh Marine and I ;'ve looked online at Bass Pro. All they have are these new-fangled plastic fuel line/tank interlocks: http://imageserv8.team-logic.com/store-logic/products/5/8680/st_8776.jpg Mine looks like this...

Homework Statement Hello, This is not a home work question but as I am not a math or physics major I need some help moving this problem forward. I am trying to calculate how much fuel (petrol/diesel/LPG) it takes to accelerate a vehicle and well to cut a long story sort I seem to be...

Hello, I am trying to calculate how much fuel (petrol/diesel/LPG) it takes to accelerate a vehicle and well to cut a long story sort I seem to be getting my units mixed up also whether I should us small or big calories. Lastly is the incline and issue that I also need to consider and how do I...

A rocket is launched vertically upwards until it uses up its fuel. It then falls back to Earth. Find the time when the rocket uses up its fuel from the graph. My answer was 20s. Is it correct?

Could somebody expain me the following questions: 1)Why hydrogen fuel cell needs catalyst (such as platinum) to operate, while elcectrochemical elements (such as zinc-air) do not? 2)Why power density increase in fuel cells leads to efficiency decrease while in electrochemical batteries it...

when approaching C the mass of your craft increases. If the mass of your fuel increases also wouldn't that mean the faster you go the more fuel youll have?

hi, what is the exact best speed for fuel economy? why is 5mph less economic than 75mph?

Homework Statement Hey, just doing a few problems and i have found i have no understanding of how to solve these types of question, if anyone can help or provide info it would be great thanks... Q " The fuel oil supplied to a boiler contains 86% carbon and 14% hydrogen by mass. Determine...

The month long debacle over the BP oil spill, and earlier collapse of a coal mine killing scores of coal miners, makes me wonder: what are the risk to human safety and environmental impact for mining, processing nuclear fuel (i.e uranium, thorium) ? Could acquiring nuclear fuel lead to a...

How much fissile material, in kilograms, would, say, an Ohio-class submarine carry? If it's classified, what would be about a good estimate?

Is there a way to make the atoms in HHO gas (Browns gas) to separte into it's elements; so the Hydrogen atoms go one way and the Oxygen in another way. By doing this I'm hoping to generate electricity from the reaction by bringing them together again. What kind of fuelcell do I need?

Hi all, I recently made my own hydrogen fuel cell and really enjoyed the process and everything I learned. I didn't know much about electronics or cells, so it was a great learning experience. In my research I found that chemical engineers made a nanometal to work as a catalyst instead of the...

I understand that generating the hydrogen that powers a typical fuel cell is (prohibitively?) energy intensive at this point, but I was curious about the following: Assuming a sufficiently efficient catalyst was obtained that allowed large-scale production of pure hydrogen without...

Hi everyone, I was looking at some data from the Energy Information Association (http://www.eia.doe.gov/emeu/mecs/mecs2006/pdf/Table3_2.pdf\) about the fuel used by different industrial processes. Under the industry of "Petroleum Refining," there is a bit of natural gas and electricity used...

I've done the leg work and have a method to go about a solution for this problem. I just need to get a second opinion before I crunch the numbers on the way I plan to go about this. 1. Homework Statement : Determine the amount of water that needs to be over a spent fuel pool to provide...

what is the average air to fuel ratio in spark ignition engines?

Sorry 1 and 2 aren't filled in very well but I have absolutely no idea what to do for this question. My brain wasn't designed for physics :( Homework Statement Question: A car traveling at 60.0 km/h has a total retarding force of 1500 N due to air resistance. If 1.00 L of petrol can...

Hey folks, I am currently doing some research on hydrogen fuel cells as part of a project. I just wanted to clear up some confusion I am having with the whole *platinum issue.* Very generally speaking, this is what I have gathered on H2 Fuel cell vehicles: 1) Electrolysis is needed to...

I think I got a and b, the rest I did my best on, and I could use some guidance! Thanks!Homework Statement 1. [6] Methane (Natural Gas) Fuel Cell. Consider a fuel cell that uses methane as fuel. The chemical reaction is CH4 + 2O2 = 2H2O + CO2 + energy (a) [0.5] Measurements reveal that...

Homework Statement A breeder reactor is designed to work on a thorium fuel cycle. If the reactor generates a constant thermal power of 2.5GW and a production rate of 233U is 52kg per year. Find the breeding Ratio [You may assume the capture to fission ratio of 233U is 0.09 and the energy...

Hi, I'm working on a commercially available PEM fuel cell and I'm trying to calculate the theoretical voltage of the cell: The only electrochemical reaction considered is H2 + 0.5O2 --> H2O And I understand that I need to use the Nernst equation: E = EO - (RT / 2F) ln (PH2O / (PH2 *...

Just don't understand how that could work, if it does. The only way I could understand it is if the amount of H cracked from input H2O is so infinitessimal that the output H2O mass is nearly unchanged and that waste product is effectively still 100% H2O. Please comment, or send me to the...

What is your opinion of http://www.cbsnews.com/video/watch/?id=6228923n&tag=related;photovideo" segment which appeared on "60 Minutes today (February 21)? It would, if it proves out, apparently make the "fuel Cell" a feasible idea for mass use. KM