What is the max Carnot efficiency?
From the Carnot Efficiency formula, it can be inferred that a maximum of 64% of the fuel energy can go to generation. To make the Carnot efficiency as high as possible, either Thot should be increased or Tcold (temperature of heat rejection) should be decreased.
Why the efficiency of Carnot engine is maximum?
The Carnot cycle achieves maximum efficiency because all the heat is added to the working fluid at the maximum temperature TH , and removed at the minimum temperature TC .
Can Carnot efficiency be 100%?
Even Carnot engine cannot give 100% efficiency because. In order to achieve 100% efficiency (η=1), Q2 must be equal to 0 which means that all the heat form the source is converted to work. The temperature of sink means a negative temperature on the absolute scale at which the temperature is greater than unity.
What is the maximum value of efficiency?
Thermodynamic efficiency limit is the absolute maximum theoretically possible conversion efficiency of sunlight to electricity. Its value is about 86%, which is the Chambadal-Novikov efficiency, an approximation related to the Carnot limit, based on the temperature of the photons emitted by the Sun’s surface.
What is the maximum possible efficiency of a heat engine?
Heat engines often operate at around 30% to 50% efficiency, due to practical limitations. It is impossible for heat engines to achieve 100% thermal efficiency () according to the Second law of thermodynamics.
Can the efficiency of Carnot engine be 0 or 1?
It can be 1 or 100% only when TL = 0K (absolute zero of temperature) which is impossible to attain practically. 2. The efficiency of the Carnot’s engine is independent of the working substance. It depends only on the temperatures of the source and the sink.
Why 100% efficiency is not possible?
in almost every case by the friction of whatever kind (resistance in a circuit, friction between gasses, friction between plates moving on top of each other, magnetic and electrical friction, or friction in waves e.g.). This is wasted energy, so you can never be able to get 100% efficiency.
What is maximum MA and maximum efficiency of the machine?
M means Mechanical advance and VR means Velocity Ratio. Efficieny = MA/VR. If MA is Max then Eff is Max. MA is Max when MA = 1/m we get MA = 1/m from law of machine P = mW+c.
What is Carnot efficiency formula?
Carnot efficiency equation The Carnot engine is the most efficient heat engine that can be built. To find its efficiency η, you need to apply the following equation: η = (Th – Tc) / Th * 100% Both Th and Tc are absolute temperatures (expressed in Kelvins).
Which of the following has the maximum efficiency?
Explanation: Carnot engine: A theoretical thermodynamic cycle proposed by Leonard Carnot. This engine gives the maximum possible efficiency that a heat engine can have during the conversion process of heat into work or vice-versa, working between two reservoirs.
Which of the following engine has the maximum efficiency?
The Carnot engine is the most efficient engine in converting heat energy to work done in a system but no practical Carnot engine can be 100% efficient in reality.
Is efficiency of Carnot engine greater than 1?
According to the Carnot theorem, the reversible engine will always have a greater efficiency than the irreversible one. The reversible heat engine operates on a reverse cycle and functions as a heat pump (or refrigerator).
Is there any machine that is 100% efficient?
A machine cannot be 100 percent efficient because output of a machine is always less than input. A certain amount of work done on a machine is lost to overcome friction and to lift some moving parts of the machine.
Can efficiency be more than 100%?
Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work). The output work is always less than the input work because some of the input work is used to overcome friction. Therefore, efficiency is always less than 100 percent.
What is maximum ma?
MA is Max when MA = 1/m we get MA = 1/m from law of machine P = mW+c.
Which of the following machine will have maximum efficiency?
Induction motor. Transformer has maximum efficiency as it is static device means it does not have any moving parts in the main body of a transformer hence no mechanical loss is counted in transformer.
How do you calculate maximum efficiency?
efficiency =WQH=1−TCTH. These temperatures are of course in degrees Kelvin, so for example the efficiency of a Carnot engine having a hot reservoir of boiling water and a cold reservoir ice cold water will be 1−(273/373)=0.27, just over a quarter of the heat energy is transformed into useful work.
Which engine has maximum efficiency *?
Diesel engines are more efficient than petrol engines at converting fuel to mechanical energy. In fact, including the energy advantage of the fuel itself, diesel engines are up to 40 per cent more efficient. Ans.
Which of the following engine has 100% efficiency?
A heat engine is considered to be 100% efficient if only all the heat is converted into useful work or mechanical energy.
Why is 100 efficiency impossible?
It is impossible for heat engines to achieve 100% thermal efficiency () according to the Second law of thermodynamics. This is impossible because some waste heat is always produced produced in a heat engine, shown in Figure 1 by the term.
What is the maximum efficiency of Carnot?
The maximum efficiency, known as the Carnot efficiency η m a x, is dependent only on the temperatures of the hot source and the cold sink T H and T L, as shown in Figure 1, and is given by the equation below The Second Law requires that waste heat be produced in a thermodynamic process where work is done by a heat source.
What determines the Carnot efficiency of a heat engine?
Figure 1: A hot source provides the energy needed to produce work in a thermodynamic process. The Carnot efficiency depends only on the temperature of the hot source and the cold sink. Carnot efficiency describes the maximum thermal efficiency that a heat engine can achieve as permitted by the Second Law of Thermodynamics.
How does a Carnot engine work?
A Carnot Engine is reversible and runs in a cycle, with all of its heat exchanges taking place at a source temperature and a sink temperature. A working engine operating between two heat temperature limits can never exceed Carnot efficiency.
Why are fuel cells not Carnot efficiency limited?
Therefore, the important point about fuel cells is not that they are not Carnot efficiency limited, rather they are (i) free from incomplete reaction or product dissociation because of the much lower operating temperatures; (ii) free from the high temperature limit imposed by materials on any heat engines and (iii)…