Ya know, I got my motorcycle license right after Richard Nixon beat Hubert Humphrey in the election of 1968 and I have been riding ever since, so it’s not like I hate motorcycles, but the Harley crowd even pxxxes me off.
I have gotten to the point that a used bike with a modified exhaust is a deal breaker, which pretty much takes me out of the market for used Harleys.
According to “Jake”:
http://www.jacobsvehiclesystems.com/about-us/environmental-health-safety/noise-concerns/
Pull quote:
The federal government has required all vehicles manufactured since 1978 to meet noise requirements when delivered to the customer, so trucks have been required to meet the requirements when they leave the dealership as new vehicles for quite some time. The real problem here is modified or defective exhaust systems. The use of the engine brake is not the problem.
In other words, if people can’t tell you are using your Jake Brake, it doesn’t matter.
So if it’s only a matter of having the correct mufflers on the exhaust system, why don’t those offending truckers just install mufflers and avoid the possibility of being ticketed for using their Jake brakes in a forbidden zone? What is the benefit of running straight pipes without mufflers?
^Gee, I thought the regulatory freaks didn’t really care how much noise it made; just whether or not you’re in compliance. Also, that no safety experts were consulted. Just “don’t use 'em; we don’t care how much difference it makes, or how safe it is.”
‘‘Dad…why is that truck farting ?’’
“Engine Brake Muffler Required” is a sign you also see. The racket caused by “Jake Braking” down a hill can be greatly reduced by muffling the system…It just costs more money…
Thats a new one on Me,what locales have those signs?I want the local towns around here to post those,some town cops are so zealous,they would give up a box of donuts for one of those signs,for a chance to write another ticket.
Another thought a true exhaust brake(which is basically a butterfly valve in the exhaust stream makes little noise)the compression brakes are the noisy rascals,all brakes work by generating heat and the release of that superheated air at TDC,makes quite a pop,when it expands.
Brakes do not necessarily have to generate heat. It just has to convert one form of energy into another. Some of those forms of energy can be stored (eg electric or compressed air hybrid). Other forms of energy cannot be stored (eg sound and heat)
I think that mufflers are ditched just before the truck pulled into the scale. Lighter equipments allow more freight to be piled on. Unlike the rest of the world, north American trucks built today generally don’t have synchronizer or a separate retarder. Both of those add weight and don’t serve their purpose while cruising
Got to disagree a little bit,heat is a fact of life in any circumstance when types of energy are con verted(heat is only molecular vibration) I dont know of anything that doesnt get warm when an energy change happens,batteries heat up, compressed air gets very hot(entropy is very much a fact of life) it is said the universe taken as a closed system will one day suffer the “heat death-entropy” when the whole firmament becomes a uniform 3k temperature(no more heat transfer, no more energy)Generators get hot in use,heat is probaly our most useful form of energy,from it springs all sort of useful things the energy of motion(kinetic),etc.Notice different conversions have different effiecencies,if all the energy in the chemical bonds of hydrocarbons could be converted into useful gas expansion due to heat,our vehicles would get much better fuel economy and there are relatively inefficient methods of storing heat(hot water,phase change or eutectic salts,etc.When the “Jake” barks it is because that hot compressed air is expanding.An unfortunate fact of life that occurred when one of the first nuclear subs settled below crush depth was that the crewmen were incinerated before they were crushed.Without heat we would have,no motion.Even the transmission retarders have oil coolers to cool the distressed oil that is pumped into a closed circut or whatever.So I maintain that most brakes utilize heat ,one way or the other,the dynamic brakes on railroad locomotives have resistance units that get really hot to help dispel the kinetic energy that is converted to.electricity.Basic rule of science"Energy can neither be created or destroyed"When Einstein postulated that mass and energy were equivalent that opened up a new can of worms.
(When a piece of steel stops a hammer,its temperature is raised,try it sometime,beat on a piece of steel with a hammer or such and see how warm it becomes)
Agreed, even the stored energy in regenerative braking turns into heat when it is used to propel the vehicle and overcome aerodynamic forces and drive train friction. What I meant was at the component level some form of braking doesn’t transform the majority of the kinetic energy into wasted heat. Compression release braking turn compressed air into vibration, another form of kinetic energy. That vibration dissipates as friction with surrounding air turn kinetic energy into heat.
At the system level, a locomotive transform kinetic energy into heat. However, the locomotive’s traction motor doesn’t turn all of the train’s kinetic energy into heat; you cannot touch its terminal without getting an electric shock during dynamic braking. Unlike the electrified rail system, there’s no way to return electrical energy back into the grid. This is why trains dump all of its kinetic energy into the resistor bank.
Good point,I think thats why we are going to see more hybrid traction engines in the future,even now some switching engines use a number of gensets with smaller motors,to have approiate power for the task at hand,weight is an asset on a locomotive,some units they call"slugs"dont even have a generator on board,they draw power from the prime mover on the main locomotive,when there is more power then traction availible,I think a number of old mining trains were battery powered
IMO,hybrid is the wave of the future.
(When a piece of steel stops a hammer,its temperature is raised,try it sometime,beat on a piece of steel with a hammer or such and see how warm it becomes)
It works better if you beat something inelastic like lead. Hammers tend to bounce off of steel with nearly the same kinetic energy after the collision as before. Hit a lead ingot and the hammer just stops, all of its kinetic energy converted to heat.
778 ft-lb of kinetic energy becomes 1 BTU of heat. You’ll have to do a lot of beating before you can feel the difference in temperature.
A 158 grain .357 Magnum bullet coming out of the gun at 1490 feet per second has 778 ft-lb of kinetic energy so that bullet adds one BTU of heat to the target that stops it and to the air that slowed the bullet down on its way to the target.
One BTU of heat raises the temperature of one pound of water by 1 degree F.
Electric locomotives (not diesel electrical) do return power to the grid when braking. That was a major innovation that improved their efficiency and made electrification popular on heavily used lines. Even some less heavily used lines in places where electricity was cheap. The hybrid car owes quite a lot to the railroads. Many advances in electric motors and generators were driven by the needs of railroads. GE and Westinghouse made most of the traction motors and generators. And in the case of GE, the majority of American diesel locomotives since the eighties (when they passed GM.) Who knows, maybe cars will eventually powered by induction systems built into the roads, or at least recharged in limited areas. That would be one way of avoiding range limitations.
yep,this technology can certainly help us,the cat is out of the bag,stop waffling manus,start making.I read about a new v8 hi performance aircraft engine that uses kerosene,said to be 50% more fuel efficient,well that is saying something about how far the efficeincy of the turbine engine has progressed,the turbines must really be getting good now,because this piston engine was really high tech,the future holds some exciting ideas(this v8 engine has enough power to get a good size helicopter off the ground)This engine should really send something like a “skylane” along in good fashion.
“v8 hi performance aircraft engine that uses kerosene”
A diesel? Who makes it?
I don’t see how the aircraft industry will ever go back to reciprocating engines. The maintenance costs are very much higher than a jet or jet turbine.
^There’s more to aviation than FAR 121 commercial flights, Bill. Most private planes are still single-engine piston powered.
correct, I was just thinking of commercial. sorry.