Engine Definition and 999 Threads

Through an intriguing fictitious dialog between Sadi Carnot and Robert Sterling, Prof. Israel Urieli of the Ohio University shows that it is not required to invoke entropy, the second law of thermodynamics, and the Carnot cycle with the [ideal] adiabatic processes in order to find out the...

Our system of interest has a duct on the left and a piston chamber on the right that make the shape of the letter T rotated 90º clockwise. The smaller tube on the left is abbreviated as P1 has an unspecified length while the piston chamber is P2. The air in P2 heats up and expands while the...

I though engine lubrication oil needs to be changed every few months or every 3 to 6 months, or every 3000 to 4000 miles, no matter what. Last time I had oil change was more than four years ago, and I have not driven the car for more than just a few miles per week, and not more than maybe two...

For my internship I have to test and certify a Marine diesel engine. We are trying to run a few tests in our workshop, but this obviously means we can't use the sea or a river as cooling. We bought an IBC tank, which can hold a 1000 liters of water. The water from the tank will be running...

A drop of fuel is ignited in an engine cylinder, that produces heat, light and sound energies from the chemical energy stored in the drop of oil. What I am not clear about is how heat energy gets transformed into mechanical work? I think the heat energy produced from ignition flows from burnt...

Hello all, I'm thinking of converting my car to Electricity. I know that some internal systems have to change. Can that work? and how?

Earth absorbs and releases a massive amount of energy as a part of the day night cycles.(~100 Peta watts of solar radiation received) And the temperature difference between the poles and equator drive weather phenomenon, which happens at an energy scale beyond technology. I am wondering if one...

The function x (t) = 4 (m · s) t − 1 + 10 m describes the position of a mass point. In which direction does the speed point at time t = 1 s? Is the amount of speed constant or not? does the velocity function change its sign for t> 0 at some point? And in which direction does the acceleration...

The answer is 6470 J. So since I have the two temperatures I could calculate the efficiency. First I convert to kelvin then get an efficiency of 0.35481. Now I can use e=W/Qin to get Qin. I get a value of 10033.54J. Now I can use e=(Qin-Qout)/Qout to get Qout, the waste heat. I get 7405.9 J...

So efficiency is W/Qin. W= 0 for isochoric processes and for the isobaric, P(change in V). So W=Pi(Vi-Vf)+Pf(Vi-Vf) Qin is negative Qs.This would happen at step 2 and 3. For the isobaric, Q=ncv(change in T) and for isochoric, Q=ncp(change in T). Now if I put everything in the equation I get...

How did you find PF?: Online [Thread moved from the New Member Intro forum, so no Schoolwork Template is shown] Hi. I'm new and am trying to solve a simple question 'Find the max power of a train engine traveling level at 50 metres per second if total resistance to motion is 30 KiloNewtons...

https://www.flightglobal.com/safety/united-777-suffers-engine-failure-over-denver/142519.article https://www.flightglobal.com/safety/united-777s-failed-pw4000-appears-uncontained-forward-cowling-missing/142520.article...

I was thinking the other day, would it be possible to have microwaves heat the air fuel mixture to activation point and have the microwaves bounce back off the gas to be picked up by a computer that generates a 3d image. this 3d image could be used to heat the gas up in a uniform way so as to...

I am attempting to solve a rather simple induction problem in Maxwell3D that I have solved before. But this time when I run it I am getting this error and can not seem to find a solution in ANSYS? I am running ANSYS Suite 2020 R1 Thank you in advance if anyone has a possible.

Hello, I'm looking for data on turboprop aircraft engine propeller efficiencies. I'm hoping for a table of available modern engines with a propeller efficiencies for comparison. I've tried Googling but not much luck. I can't even seem to find propeller efficiencies on the individual engine...

I post the working in the attached file

Please help answering

Given we only have one number I assume we are to use Poisson distribution. Probability for a plane with two engines to fail require both engines to fail: $$P_2 = P_o(2) =p^2/{2!} * e^{-p}$$ Probability of a four engine plane to fail requires 3 or 4 engines to fail: $$P_4 = P_o(3) + P_o(4) =...

Is it possible to put multiple accelerator grid in ion engine instead of one? So we will get higher exhaust velocity and benefit for us right? or is there any disadvantages?

I'm trying to simulate the physics of a Toyota Camry during acceleration with a time granularity of 100ms. My simulated conditions are as follows: m = 1590 kg v = 17 m/s a = 1.5 m/s2 η (transmission efficiency) = 0.85 rwheel = 0.35 m Fdrag = 100 N Ffriction = 260 N Faccel = 1590 kg × 1.5 m/s2 =...

Hello All The power output of piston engines fitted to aircraft were (and still are?) specified in terms of their HP rating, whereas jet engines are typically rated in terms of their trust. For example, a Mosquito two engined fighter/bomber was equipped with two Merlins, each producing...

Hi folks, Any idea about what is it? I am required to find parts like these items which are made of stainless steel 304 and used on the post-treatment of diesel engine gas.

What is most important parameter when we must build long last internal combustion engine and why? specific output : HP/Displacement ? HP per each cylinder? Torque per cylinder? Displacement per cylinder? HP / piston area ? RPM / displacement of one cylinder? Numbers of cylinder? Low RPM as...

Have a thick steel hollow sphere with a inside radius of 20 cm. Then fill it up with sulfuric acid and add water. Then remove the oxygen ions. then give the sphere a negative charge and all the hydrogen ions move to the surface of the inside sphere. then charge sphere positive and the hydrogen...

I have a question about building efficient heat engines in outer space. In theory you could have a hot reservoir heated by the sun that was several hundred degrees C, and a cold reservoir that was very cold - maybe 50K - 100K or even colder. Thus, theoretically at least, a heat engine could be...

So I tried to solve this in two methods, but I keep getting different results, and I don't know why.

So I found this steam engine on the youtubes: Consider the system not including the candles, only including the can that makes up the boiler shell and the piston, flywheel, etc. The boiler can acts as a hot reservoir; however, the Kelvin-Planck statement of the 2nd law says you can't have an...

Hi, I have to measure the HP of a small engine at the crankshaft. The only usable things are. A dinamometer A brake disk An rpm meter The brake caliper is floating so when we apply de load it pull the dinamometer. The rpm meter show the revolution during the load apply. It can works? How I...

Hi everyone, online I ve seen some images about 2 stroke carbureted turbo (motorcycle derivation engine). Now.. In the past in this forum some members spoke about turbocharging 2 stroke but not in sufficient detail. The intake and the exhaust are open at the same time and there are no valves...

I am trying to understand what happens in the engine (especially gasoline vehicles) during coasting (in drive mode) and engine braking. It looks like both mechanisms shut off the fuel injectors. Then how is the former (coasting in drive mode) able to use the momentum while the latter (engine...

Nota that the path a to b is isothermal since J is proportional to L, then we can find the value of T_a and T_b using the equation of state and the figure. We have, \begin{equation} J_0=\alpha L_0T_b \end{equation} or \begin{equation} T_b=T_a=\frac{J_0}{\alpha L_0}=T_0 \end{equation} Also, by...

If a heat engine converts heat into "work", will ice used to run a Stirling heat engine last longer than ice allowed to melt by itself? To try and answer this, I obtained a Stirling engine and ran this experiment: With the engine running: And not running: Without the engine running the...

https://phys.org/news/2020-06-year-old-theory-alien-civilization-exploit.html Do we think this makes it possible using a Black Hole? Seems highly likely that it could be used as a power source one day if we are around long enough to sufficiently advance enough to make this possible.

I'm really struggling with this problem. I can't understand which are the forces that i need to calculate work. Probabily when the sand falls the force of which i need to calculate work is weight force, but which is the force that carries the sand at the top of the roller?

Let the new engine, NE, extract heat from a certain subset of these baths, and let heat obtained from the ##i^{\rm th}## bath be denoted by ##Q_i##, and let the heat rejected to the ##j^{\rm th}## be denoted by ##Q_j##. Let the engine perform an amount of work ##W##. Now right beside this...

Hello, I am doing a study for my final years Uni project, which includes waste heat recovery from gas fuelled engine exhaust. I am using a data sheet for a Jenbacher J620 engine-. In the data sheet it is stated that; exhaust gas mass flow (wet) = 17325 kg hr ( not sure about the wet part?)...

Hello, I have designed a gearbox that bolts on to a fixed engine and fixed pump. It is completely supported by them. The total mass of the gearbox and the components attaching it to the engine and pump is 7.7kg. Its centre of mass is 0.167m along the x-axis and 0.09m along the z-axis from the...

A Rankine Cycle heat engine uses ammonia as a working fluid, turbine entry temperature is 25 Bar at 60 degrees Celsius. The turbine outlet pressure is 4 Bar, the question is: what is the outlet temperature? and if the output power is 6 Gigawatt (6x10^9 watt) what would the mass flow rate of the...

Hi, I am quite confused about how to approach this problem. I have seen variations of this problem where there is a heat engine between two blocks, but in this case the surroundings are massless, so I don't believe that approach will work here. Method: I have first started with the case that...

My attempt: I though : ΔQ_w= 1*4200 * (-100) J=-420000J Q_ice=334000*m_ice = ΔQ_w But it was totaly wrong! The solution showed : Because the heat engine is reversible the efficiency η = 1- (T_cold / T) T_cold is always 273 K while the hot temperature changes from 373 K to 273 K during this...

Hello All, Happy New Year! A typical modern turbofan engine system creates lift as well as propulsion for the aircraft. Somewhere inside the system, the fast rotating device also works as a generator (alternator) to produce the electricity powering electrical/electronics equipments. What is the...

For the most part, I ignore seeming cranks on other platforms, but the persistence - and insistence - of one who keeps claiming what looks to be physically impossible attributes of his ICE engine finally triggered my "Okay, I'll ask some experts." His written posts are along the lines of this...

Here's my attempt for the first part: For the first body, the work obtained is ##W_1 = C_P (T_1 - T_f)## while for the second body, it is ##W_2 = C_P(T_2 - T_f).## So the net work obtained is the sum of these two: ##W = W_1 + W_2 = C_P (T_1 + T_2 - 2 T_f)## and that proves the first part...

A diesel engine explodes and literally shoots out of a tractor pulling truck. Apparently this type of thing is fairly common in the sport of tractor pulling, but it's much more common for the engine to simply explode.

The first picture was provided along the problem statement. The second has my annotations. I initially began by calculating the ratio of efficiencies, since the work done is obviously the same and cancels out, but after failing and having seen the form of the solution I saw that that cannot...

i need a simple calculation of a stirling ltd surface area calculation per watt produced and would a very rough surface and very large surface area hinder heat flow if the distance to re generator is extreme /would folding the surface area of a flat plat ltr help increase the power of engine...

Hi, I was just wondering about the efficiency of a cycle that is not Carnot cycle. In that case one should use \eta = 1-\left|\frac{Q_{\rm out}}{Q_{\rm in}}\right|, where Q_{\rm in} and Q_{\rm out} are the amounts of heat absorbed and released during the cycle. For instance, I guess that in...

Q2: An engine has power of 26.5 kW, needs 9 kg coal during an hour for energy. The heat capacity of coal is 7800 cal/g. Define the engine’s efficiency. Qh= mcΔT = 9000x7800xΔT ( stuck) P=26.5kW(is this the power output of the engine in an hour?) If only I could find ΔT, thenI would be able to...

Attached is an example from my Tipler physics book of a determining the power delivered from a cars engine. I get the derivation(math), but am having some issues with the understanding/concept. Mainly, isn't Power=Work done/time. If so, they define the system as Car-earth. There is no external...

I took my car to the shop and they had it for 3 straight weeks even changed the spark plugs but they never could figure out what was wrong with it. Now that it's getting cooler weather it's taking bout 2 hours of having the hair dryer blowing on the back of the engine for it yo start up, does...