Contents

- 1 What is the formula of thermal efficiency?
- 2 How is thermal efficiency of a diesel engine calculated?
- 3 What is the formula for efficiency of Carnot engine?
- 4 How do we calculate efficiency?
- 5 What are the two factors of thermal efficiency?
- 6 What is the efficiency of diesel cycle?
- 7 Which cycle has more efficiency?
- 8 What is the efficiency of diesel engines?
- 9 Is Carnot engine 100 efficient?
- 10 How do you calculate cycle efficiency?
- 11 How do you calculate engine efficiency?
- 12 How do we calculate time?
- 13 What is work formula?
- 14 Can you have over 100 percent efficiency?

## What is the formula of thermal efficiency?

quantities are heat-equivalent values. So, for a boiler that produces 210 kW (or 700,000 BTU/h) **output** for each 300 kW (or 1,000,000 BTU/h) heat-equivalent input, its **thermal efficiency** is 210/300 = 0.70, or 70%. This means that 30% of the energy is lost to the environment.

## How is thermal efficiency of a diesel engine calculated?

The input and output energies and the **efficiency** can be **calculated** from the temperatures and specific heats: It is convenient to express this **efficiency** in terms of the compression ratio r_{C} = V_{1}/V_{2} and the expansion ratio r_{E} = V_{1}/V_{3}. The **efficiency** can be expressed in terms of the specific heats and temperatures.

## What is the formula for efficiency of Carnot engine?

Your first **equation** is correct, but your second one isn’t. For the **Carnot engine**, the **equation for efficiency** with respect to temperature is [eff = 1+(Tc/Th)].

## How do we calculate efficiency?

The work **efficiency** formula is **efficiency** = output / input, and you can multiply the result by 100 to get work **efficiency** as a percentage. This is used across different methods of measuring energy and work, whether it’s energy production or machine **efficiency**.

## What are the two factors of thermal efficiency?

In theory, the factors that affect thermal efficiency (the performance of an engine or the work it has done in relation to the value of heat supplied to it) are the **heat input** and the heat output. Additionally, **temperature variations** also come in play, the amount and the rate of losing or gaining heat.

## 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**.

## Which cycle has more efficiency?

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.

## What is the efficiency of diesel engines?

Diesel Engines

Engine type |
Thermal efficiency |
---|---|

4-Stroke, spark-ignition engine |
30% |

2-Stroke, spark-ignition engine |
22% |

4-Stroke, DI compression-ignition engine |
40.3% |

2-Stroke, DI compression-ignition engine |
43% |

## Is Carnot engine 100 efficient?

Solution: η=1-T2T1 for **100**% effeicency η=1 which gives T2=0K.

## How do you calculate cycle efficiency?

The **efficiency** of the **cycle** is obtained by comparing the **total** work W to the **total** heat input QIN. β = V4/V3 is the cutoff ratio. (V3 = V2.) γ = CP/CV is the specific heat ratio.

## How do you calculate engine efficiency?

An Example. If 200 joules of thermal energy as heat is input (), and the **engine** does 80 J of work (), then the **efficiency** is 80J/200J, which is 40% **efficient**. This same result can be gained by measuring the waste heat of the **engine**.

## How do we calculate time?

To solve for **time** use the formula for **time**, t = d/s which means **time** equals distance divided by speed.

## What is work formula?

We can calculate **work** by multiplying the force by the movement of the object. W = F × d. Unit. The SI unit of **work** is the joule (J)

## Can you have over 100 percent efficiency?

It is thermodynamically impossible to **have** an **efficiency** of **more than 100**%, as this implies that more energy is being produced than is being put in. For this reason the performance is expressed as a Coefficient of Performance (COP) rather than an **efficiency**. The **above** example **would** be expressed as **having** a COP of 3.