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Compression ratio (CR) is the total volume of a cylinder at BDC (bottom dead center) divided by total volume of space at TDC (top dead center).
To increase CR, you must either increase the total volume of displacement, or decrease the volume at TDC. This can be achieved by shaving the heads, increasing the bore, or increasing the stroke.
Provided there is room for valve clearance, shaving the heads is the simplest method.
Wiki User
∙ 11y ago
Wiki User
∙ 12y agoThe efficiency of a Carnot engine can be calculated from the formula:
ε = 1 - TC/TH
where
ε is the efficiency,
TC is the absolute temperature of the heat sink or "cold reservoir"
TH is the absolute temperature of the heat source or "hot reservoir"
The efficiency can thus be increased by decreasing the temperature of the heat sink and/or raising the temperature of the heat source.
Wiki User
∙ 15y agoTurbo charging or super charging can give significant gains. Also, cold air intakes can raise the output of an engine by approximately 5-10 HP.
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Is the energy of carnot engine is maximum?
The work output of a Carnot engine would be the maximum possible, i.e. it would yield the maximum possible efficiency for conversion of input energy into useful work.
Is it possible to attain an efficiency of 100 percent in heat engines?
The maximum efficiency of the carnot engine only depends on two factors: 1 - The temperature of the hot reservoir (TH) 2 - The temperature of the cold reservoir (TC) And is given by (TH - TC) / TH « or » 1 - TC / TH So by that we can see the maximum efficiency (100%) would be when the difference of temperatures between the two reservoirs is infinite.
How would you increase the efficiency of a Carnot engine by increasing T1 or by decreasing T2 - why?
Increasing the temperature of the hot reservoir will increase efficiency. So will decreasing the temperature of the cold reservoir (heat sink). There are limits as to how cold you can get the heat sink however. Cutting the temperature of the heat sink in half will give the same improvement in efficiency as doubling the temperature of the heat source - but it's a lot harder to cut the temperature of the heat sink in half than to double the temperature of the heat source. Also, the heat sink is usually around the temperature of the environment - which you have little control over. ... bottom line - you are probably going to find it easier to improve the efficiency by raising T1 than by decreasing T2.
Is it possible to improve mileage with supplemental hydroxy gas produced on board on demant from water?
No. To turn the water into gas you'd need electricity, which you'd get from the alternator- which'd increase the load on the engine-which'd increase the fuel consumption. On top of that the sheer volume of gas that an engine would require is more than what can reasonably be produced by a car-mounted accessory.
Can you put cold water on compressor outside to increase efficiency of ac?
No. Cooling the compressor will do little to improve the efficiency of the system. The compressor will be slightly more efficient, but the overall efficiency of the heat transfer will be unchanged. Cooling the condenser (the outside heat exchanger coils) will do more, but the money saved in AC costs will be offset by water wasted. Also, keep in mind the heat exchanger outside is an electrical device. It is designed to withstand rain on it, not water being hosed in it. Be carefull. This idea is half-cocked and I would not recommend it.
Is the energy of carnot engine is maximum?
The work output of a Carnot engine would be the maximum possible, i.e. it would yield the maximum possible efficiency for conversion of input energy into useful work.
Does an ideal machine would have an efficiency greater than one?
No, an efficiency greater than one would not be possible, since that would violate a very fundamental law of physics: conservation of energy. The efficiency of an "ideal machine" would be one, in many cases; the efficiency of an ideal Carnot engine would be less than one.
What happens to the efficiency of a heat engine when the temperature of the reservoir into which heat energy is rejected is lower?
Efficiency would increase.
Why would Engine temperature increase at idling?
Because the efficiency of the fan and the water pump degrades at low RPM.
What is a carnot's engine?
a Carnot cycle is a perfect cycle of energy conversion from heat to mechanical energy and back without loss. This is an impossibility due to losses inherent in any energy transfer. A Carnot engine would theoretically use all available energy for each energy transfer.
Is it possible that in an engine there will be an 100 percent efficiency without the presence of friction and other irreversibility?
No. No engine can be 100% efficient. The Carnot cycle is mathematically proven to provide an upper bound for efficiency. The efficiency of the Carnot cycle can be calculated from the formula:eta = 1 - Tc/THwhereis eta is efficiencyTc is the temperature of the heat sinkTH is the temperature of the heat source.The only way to make the (theoretical) efficiency 100% would be to have a heat sink at absolute zero (which is impossible due to the 2nd law of thermodynamics) or to have the heat source at a temperature of infinity (which is impossible due to the 1st law). Real engines always operate at an efficiency less than the theoretical because they operate on a less efficient cycle and/or posses real irreversibility in their operation. Consequently no engine - real or theoretical - can operate at 100% efficiency.
What is the ideal efficiency of a heat engine that operates with its hot reservior at 500k and its sink at 300k?
Using Carnot's equation of ideal efficiency, N= 1-C/H C is the temperature of the cold reservoir and H is the temperature of the hot reservoir. So it would be N= 1-300/500= .4 or 40%
Is it possible to attain an efficiency of 100 percent in heat engines.explain?
A heat engine operating between 2 temperatures, Thot, the heat source, and Tcold, the heat sink, can be 100% efficient only when Tcold is absolute zero. Carnot worked out the equation to determine the best possible efficiency of a heat engine designed to produce mechanical energy ("Work") from heat energy: Wout = (Heat Energy in at Thot) x (Thot - Tcold)/(Thot) Note that (Thot - Tcold)/(Thot) is 1 only if Tcold is zero. In every other case, the ratio is less than 1. The amount of heat energy discharged to the heat sink at Tcold is: (Heat Energy in at Thot) - Wout. (You can work this out from the equation. It reflects the law of conservation of energy. ) This just means that all the heat energy absorbed by the heat engine is converted into either mechanical energy or heat energy at a lower temperature. No energy is lost and no extra energy is created. "Efficiency" according to Carnot's equation tells us the best possible ratio between these two energy outputs that nature allows a heat engine to achieve. You can think of a heat engine as a device that splits an amount of heat energy at some high temperature into mechanical energy and heat energy at some lower temperature. Kind Regards, Colin Dunstan Author: "cyclic heat to work conversion systems"
What is carnots engine?
a Carnot cycle is a perfect cycle of energy conversion from heat to mechanical energy and back without loss. This is an impossibility due to losses inherent in any energy transfer. A Carnot engine would theoretically use all available energy for each energy transfer.
How do you increase thermal efficiency in converting heat energy to mechanical energy eg in internal combustion engine or gas turbine is there any device to improve thermal efficiency?
The first step would be to insulate the system to decrease heat loss then increase the compression ratio of air/fuel mixture as in the ic engine The first step would be to insulate the system to decrease heat loss then increase the compression ratio of air/fuel mixture as in the ic engine
Is it possible to attain an efficiency of 100 percent in heat engines?
The maximum efficiency of the carnot engine only depends on two factors: 1 - The temperature of the hot reservoir (TH) 2 - The temperature of the cold reservoir (TC) And is given by (TH - TC) / TH « or » 1 - TC / TH So by that we can see the maximum efficiency (100%) would be when the difference of temperatures between the two reservoirs is infinite.
How would you increase the efficiency of a Carnot engine by increasing T1 or by decreasing T2 - why?
Increasing the temperature of the hot reservoir will increase efficiency. So will decreasing the temperature of the cold reservoir (heat sink). There are limits as to how cold you can get the heat sink however. Cutting the temperature of the heat sink in half will give the same improvement in efficiency as doubling the temperature of the heat source - but it's a lot harder to cut the temperature of the heat sink in half than to double the temperature of the heat source. Also, the heat sink is usually around the temperature of the environment - which you have little control over. ... bottom line - you are probably going to find it easier to improve the efficiency by raising T1 than by decreasing T2.
