Table of Contents
- 1 How can the efficiency of a diesel cycle be increased?
- 2 Why does brake thermal efficiency increase with load?
- 3 Does efficiency increase with load?
- 4 Does brake power increases with increase in load?
- 5 Does air standard efficiency of Diesel cycle decrease as the load increases?
- 6 How can we improve the efficiency of diesel engines?
How can the efficiency of a diesel cycle be increased?
The efficiency of the diesel cycle increases
- with increase in cut-off ratio.
- with decrease in cut-off ratio.
- remains unaffected.
- unpredictable.
Why does engine efficiency increase with load?
Losses due to friction are essentially constant with respect to load so at low loads, the majority of your input power may be used to overcome friction. As the load increases, friction plays a smaller and smaller role in the overall efficiency.
What is the efficiency of diesel cycle?
A typical diesel automotive engine operates at around 30\% to 35\% of thermal efficiency. About 65-70\% is rejected as waste heat without being converted into useful work, i.e., work delivered to wheels. In general, engines using the Diesel cycle are usually more efficient than engines using the Otto cycle.
Why does brake thermal efficiency increase with load?
Brake thermal efficiency It increases with an increase in load in case of all the blended fuel tested. This can be attributed to reduction in heat loss and increase in power with increase in load.
Why does diesel cycle have high efficiency compared to Otto cycle?
3. 6 Diesel Cycle. Although for a given compression ratio the Otto cycle has higher efficiency, because the Diesel engine can be operated to higher compression ratio, the engine can actually have higher efficiency than an Otto cycle when both are operated at compression ratios that might be achieved in practice.
How is the heat added in diesel cycle?
The Diesel cycle is a combustion process of a reciprocating internal combustion engine. In it, fuel is ignited by heat generated during the compression of air in the combustion chamber, into which fuel is then injected.
Does efficiency increase with load?
Increasing the clock frequency leads to increasing power consumption, thus efficiency decreases with increasing clock frequency. Therefore, efficiency increases with increasing load current.
What is the efficiency of diesel engine?
Diesel engines have a high efficiency (up to 45\%) in power generation and can also be adapted to combined heat and power systems (CHP). Medium- and slow-speed engines are known for fuel flexibility and can operate on low-grade fuels.
Why efficiency of Diesel engine is high?
Diesel engines are more efficient than gasoline engines for two reasons: (i) higher cylinder pressures and corresponding higher temperatures lead to improved thermal efficiency for the diesel engine; (ii) the air throttling required to control the gasoline engine power output reduces engine efficiency and is not used …
Does brake power increases with increase in load?
As the load increases, the brake power produced by the engine also increases for all blends of fuel. …
What is brake thermal efficiency?
Brake thermal efficiency is a measure of the fuel efficiency of internal combustion engines. The higher the brake thermal efficiency, the lower the fuel consumption, and greenhouse gas emissions.
Which cycle efficiency is within diesel and Otto cycle?
Explanation: Otto cycle is more efficient than Diesel cycle for a given compression ratio. 6. For constant maximum pressure and heat input, the air standard efficiency of the gas power cycle is in the order.
Does air standard efficiency of Diesel cycle decrease as the load increases?
Yes. Air standard efficiency of diesel cycle decreases as the load is increased. The simple reason is that with increase of load, cut off ratio also increases. With increase of load more fuel will be injected in combustion chamber.Hence ratio of volume before combustion to volume after combustion will also increase.
How does compression ratio affect the efficiency of a diesel engine?
It shows that as we increase the load, efficiency of diesel engine increase at start, as more amount of air is sucked in and high compression ratio results in higher efficiency. You can also think in this way that as the load is increased the ratio of friction to brake power goes down.
What happens when the load is increased in a diesel engine?
In a Diesel engine as load is increased , we will be giving more throttle to maintain the specified RPM. Hence more fuel will be injected into the cylinder ( pulse width is increased ).
How can we improve the efficiency of diesel engines?
The pending U.S. decision on the engines standards could be the only real action to substantially improve the efficiency of diesel engines for the next 10–15 years. For that reason, a strong case can be made that they should push the technology envelope as hard as is feasible based on emerging efficiency technologies.