Questions tagged [engines]
The engines tag has no usage guidance.
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Which rocket engines used this exotic cycle?
A "Hypergolic, Full Flow, and Closed Catalyst" cycle rocket engine
Left side:
All hydrazine goes through the centrifugal fuel pump
All hydrazine undergoes thermal decomposition
Out of it ...
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How to calculate clearance volume in internal combustion engine of a tractor?
To begin with, a tractor engine is provided to identify and calculate the terminologies associated with it. The bore diameter and stroke length is given as 15.84 cm and 8 cm respectively. Having ...
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Why do engines with cylinder offset not suffer from increased frictional losses on the compression and exhaust strokes?
I recently watched the D4A YouTube video on cylinder offset, and for the most part it makes sense. Longer power and intake strokes, lower frictional losses on the power and intake strokes, greater ...
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Do the models of reversible cycles like the Carnot Cycle help engineers in any way to design real Heat engines?
Is there any use in engineering for this kind of very abstract models other than setting an unachievable upper bound on the possible efficiency of heat engines? Can they help in the design of more ...
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Nuclear pulsejet
As the title suggests, I am wondering about the feasibility of Nuclear powered pulsejet engines, including Radioisotope Thermoelectric Generators (RTGs). I am not talking about Nuclear pulse rockets, ...
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Need for diaphragm carburetors in small internal combustion engines that run on gasoline
I have seen that hobby internal combustion engines that run on gasoline always use diaphragm carburetors instead of the very simple carburation system used by glow engines that generally consist only ...
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How to interpret the Otto Cycle PV diagram?
AFAIU this is the practical Otto cycle with the added isobaric stroke for when the piston intakes and expells through the valves.
However, there's one thing I don't understand: AFAIK, PV diagrams ...
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Unstuffed to Stuffed Two Stroke Engine
I'm working on a Puch e50 Engine.
The original engine used an unstuffed crank that had bushings instead of bearings. I've rebuilt the engine using new seals, bearings, and an aftermarket stuffed ...
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Diesel vs petrol NOx / PM?
I am interested in the comparison of NOx and particulate matte (PM) for modern (Euro 6) diesel engines vs petrol engines? Are the exhaust products produced by both equally carcinogenic?
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Why modern diesel engines have low compression ratio?
Modern diesel engines have low compression ratio (some only 14:1, old diesel has 23:1), if compression ratio is directly connected to thermal efficency, how this engines achieve good efficency?
Can ...
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Why are bulldozers so slow?
Tracked-type tractors and bulldozers are very slow engineering vehicles. Their top speed is less than 15 km/h and when pushing it is even lower (< 5 km/h). For example: the Caterpillar D9's top ...
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Effect of Earth's rotation on moving vehicles
The earth rotates at a rate of 460 m/second. I wish to predict the position and approach for landing an UAV (quadcopter) on the vehicle.
I have a free-moving landing platform on vehicle that aligns ...
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how to plot power output graph for motors
What is the best way to plot motor power output graphs? Does anyone know how we can plot this graph for motors and engines?
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What are the issues with this ICE design?
Elaborating along this previous question, could you please invalidate this ICE design with solid authoritative arguments explaining all the flaws?
Starting hypothesis:
Whatever the purpose, one single ...
user12750
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Could electromagnets ever compete with the power of an antimatter annihilation engine? [closed]
So to make this easier to read, I've been using a few terms I'll explain really quick
"MPP": (maximum physical potential)
"MASS": (maximum atomic structure strength)
According to ...
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Throttle position as a function of engine torque and speed
In the figure attached showing the throttle position versus an IC engine produced torque, I didn't understand why does the torque value at a specific rpm vary for different throttle positions. My ...
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Why is Scotch-Yoke mechanism not used for internal combustion reciprocating piston engines?
Regarding piston acceleration variations due to the geometric nature of crankshaft and connecting rod motion, in relation to connecting rod length and bore to stroke ratio.
Why is Scotch-Yoke ...
user12750
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Why did WW2 torpedoes use wet-heater engines instead of piston engines?
I understand how both types of engines work, but I don't understand the pros and cons of using one vs the other.
Why are wet heater engines so suitable for torpedoes, but seemingly no other ...
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Wheel's torque and differential gearbox
I know that the differential gearbox is providing a torque to the wheels; as the relation in the figure indicates : Tw (wheel torque) = Td (differential torque) × (ηd×nd). Where nd:is the differential ...
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Shifting Between Gears To Achieve Higher Acceleration
If the car's acceleration is higher when the wheel's angular acceleration is higher(tangential acceleration=alpha x radius). Why are higher gears not used to accomplish the acceleration of the car ...
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Question about engine reaction torque from gas forces
in the figure below the reaction torque equation is given by Fg41.x trying to rock the ground plane about the O2 pivot due to gas forces . My question is if the piston with the cylinder whole assembly ...
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How friction between stator and rotor is dealt with in an electric engine/motor
This YouTube video https://www.youtube.com/watch?v=nlG2dsYRagI shows how an electric engine is made but I don't understand how friction between the stator and rotor is dealt with.
At 3:50, we see the ...
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Question about torque in car engines
Sometimes people say "The engine of Car A has a higher torque than Car B with both having the same horsepower" My question is : if both cars are equal in horsepower can't we just avail this ...
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How to sense off-idle in internal combustion engine?
What is the simplest way to sense off-idle in an internal combustion engine? I am currently focusing on roadgoing and tractor, but would like as general-case a solution as possible. Priority is on ...
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Where does all the inherent vibrations in an internal combustion or jet engine come from?
I am trying to understand that why does a piston engine produce vibrations? What is the source of it and how will it cause the whole internal combustion engine to vibrate in response? Will jet engines ...
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Does the turboprop engine torque get transferred to the engine mount and ultimately aircraft when engine is active?
When the turboprop engine is active, the propeller shaft rotates and causes the propeller to rotate as well, which in turn generates thrust. The propeller shaft rotates because of the torque (or ...
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Alcohol as a working fluid?
Alcohols with their lower boiling point and overall non-toxicity, could they be used as a turbine working fluid instead of steam water?
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Why doesn't the aircraft propel forward when on ground and the engine is running?
For a car, we know that we need to use the gear system in order to move the car forward. For the aircraft, I don't know if there exists any gear system within it? I have seen aircrafts staying at the ...
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Out of the three types of Stirling Engines, which one is the most efficient and delivers the most amount of power?
I was thinking that the beta Stirling engine would be the most efficient as it has a displacer to block heat transfer from the hot to cold regions in between thermodynamic cycles. However, I heard ...
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What are the benefits of reducing valve duration in an engine?
From my understanding this would be beneficial if you've taken a stock engine and put a smaller, more restrictive air intake on it.
It would also be done to create more low end torque which shifts the ...
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Could engines run on 1 cylinder while idling to save fuel?
Could engines run on 1 cylinder while idling to save fuel? And then either each "idle" session alternate a different cylinder so wear and tear is even, or change the active cylinder ...
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Theoretical maximum pressure from combusting LPG
I am curious how to find or estimate the theoretical maximum pressure that the combustion of a LP gas, such as propane, can produce inside of a constant volume, such as in a cylinder.
I know what the ...
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at what point is increasing pressure ratio diminishing in returns?
piston engines of ww2 planes had pressure ratio of at least 10, while jet engines were still vastly superior with a pressure ratio of only 3.
Certainly pressure ratio of 1 would bring 0% fuel ...
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Replicate stepper motor with gasoline engine
For those unaware of what a DC stepper motor is, it boils down to an electronic motor where the rotation can be precisely controlled, i.e. you can control the rotation of the motor in fractions of a ...
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Could you use anything as a fuel source for an engine or motor, if it's designed to use that specific type of fuel?
By anything I don't mean to put some random liquid in a car engine, but is it possible to design and build an engine or motor that could use something like tea or orange juice for it's fuel? I know it ...
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In a diesel engine, does more heat leave the engine through the tailpipe or the radiator?
Diesel exhaust is hot, and there's a lot of it.
Diesel radiators also get pretty hot.
In a typical diesel engine, which one is dissipating more heat?
EDIT: In response to a request for specificity ...
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Relation between engine size and its power to weight ratio
Is there a relation between engine size and its power to weight ratio? For example if you shrink the engine to half the size will it have exactly half the power?
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Understanding a Variable Lift Valve Train Patent
So my father has this patent, and I'm not entirely sure how a certain aspect of it is supposed to be working. I understand how it can be useful, but I don't understand how such a seemingly simple ...
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Is there a reason (in terms of the physics involved) why it is better to push start a car in 2nd gear rather than 1st?
I am struggling to understand why it is recommended to push start a car in 2nd gear rather than 1st - in terms of the physics involved, I fail to see a reason why this would be the case. I have ...
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Ignoring Mechanical Material Properties and Design Implications, in a Compressor, does the Thermal Density of the Blades Affect Efficiency?
Consider an ideal adiabatic compressor, ignoring the remainder of the thermodynamic cycle. In this case, the heat flow q into and out of the compressor itself is zero, by definition of adiabatic ...
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Why do custom engines typically specify a type like "Ford" or "Chevy"?
I notice that when custom car engines are sold they nearly always have a big name type name like "Ford" or "Chevy". Is this because the block and crankshaft comes from those companies and the custom ...
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When does the minimum temperature in a four-stroke cycle occur inside the engine cylinder?
I've checked on quite a few places on the net and some say it occurs at the beginning of suction stroke and others say at the end of suction stroke. I believe it to be at the end of suction stroke ...
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Relationship between Heat Flux and Engine RPM
I'm doing a project that involves knowing the average steady-state heat dissipation rate of a single cylinder air-cooled engine (through the engine wall and fins) at a given RPM. The problem is that I ...
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What developments made diesel engines suitable for personal cars in the 1970s/1980s?
Both diesel and gasoline engines were developed in the late 19th to early 20th century. Diesel engines were for the most part of the 20th century used mostly for large applications in ships, trains, ...
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Effect of Pressure on Combustion efficiency (of hydrogen) in excess air
Can somebody explain relation between combustion efficiency and pressure in lean mixtures using any kind of chart or mathematical equations?
At first glance I thought, combustion efficiency increases ...
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How do turboshaft engines maintain a constant rpm regardless of load?
I understand that most turboshaft engines tend to run at (or close to) their most efficient rpm all of the time, and it is the load that is changed e.g. the pitch of the blade pitch on helicopters.
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What are the non-practical features of a sterling engine that cause the internal combustion engine to be used instead?
What are the non-practical features of a sterling engine that cause the internal combustion engine to be used instead (in a car)? (e.g. price, size, the power to weight ratio, etc.)
Can you name any ...
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PLEASE ANSWER Sterling vs Combustion Engine
This may be difficult to answer but, theoretically, if you had a car with a sterling engine that produces say approximately 300 horsepower how much of any specific heat source would need to be used if ...
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Efficiency of an engine
What is meant by thermodynamic efficiency of an engine?
and what are the factors that affect the thermodynamic efficiency of a diesel engine?
user19926
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How do external irreversibilities decrease the efficiency of thermodynamic cycles?
In gas power cycles, one mentioned that:
The Carnot cycle is both externally and internally reversible.
Therefore making the Carnot cycles more efficient than other practical
cycles.
Question:
...
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