What is delay period of CI engine combustion?

Abstract The ignition delay in a diesel engine is defined as the time interval between the start of injection and the start of combustion. This delay period consists of (a) physical delay, wherein atomisation, vaporization and mixing of air fuel occur and (b) of chemical delay attributed to pre-combustion reactions.

What is delay period and what are factor affect it?

I C ENGINES – II Air Motion & Combustion •Factors Affecting the Delay Period : – Intake temperature and pressure : Increase in intake temp. increases compressed air temp. resulting in reduced delay period. Preheating may not be desirable as it reduces density of air affecting volumetric efficiency and power.

What is delay period?

Your cycle Missed or late periods happen for many reasons other than pregnancy. Common causes can range from hormonal imbalances to serious medical conditions. There are also two times in a woman’s life when it’s totally normal for her period to be irregular: when it first begins, and when menopause starts.

What is delay period in CI engine What is the difference between physical delay and chemical delay?

After physical delay period is over, the time interval upto the time the fuel auto-ignites and flame appears is called chemical delay. During this period preflame reactions take place. This period corresponds to ignition lag of S.I. engines.

What is the delay period?

What causes ignition delay?

The longer ignition delay can be caused by a number of factors including: lower intake air temperature, lower boost pressure due to turbocharger lag, lower combustion chamber wall temperature and more advanced dynamic injection timing.

How many days are normal for a period delay?

That means that a 28-day cycle one month and a 26-day cycle the next month is probably nothing to worry about. Your period might be considered late if: It’s been more than 38 days since your last period. You’re normally really regular, and your period is more than three days late.

What is physical delay discuss the factors that affect the delay period in a CI engine?

Engine operating variables such as speed and load affect the ignition delay because they change the primary factors such as injection pressure, compression temperature, pressure and air velocity. It has been found that under normal running conditions, compression temperature and pressure are the major factors.

What is the difference between ignition lag and ignition delay?

In the internal combustion engine, the time interval between the passage of the spark and the inflammation of the air-fuel mixture. Also known as ignition delay.

How do I reduce ignition delay?

Hence, if n 2 is somewhat increased prior to the fuel being exposed to oxygen, the observed ignition delay, τ, should decrease. According to the two energy level system, τ can be decreased simply by increasing the fuel temperature prior to injecting or exposing the fuel to oxygen.

What is ignition delay period in a CI engine?

Ignition Delay Period At this first stage of combustion in the CI engine, the fuel from the injection system sprayed in the combustion chamber in the form of a jet. Due to atomization and vaporization, this fuel disintegrates at the core which is surrounded by a spray of air and fuel particles.

What is the purpose of delay period in a jet engine?

4. Delay period serves a useful purpose in that it allows the fuel jet to penetrate well into the combustion space. Explanation: None. 5. If the delay is too short the amount of fuel available for simultaneous explosion is too great and the resulting pressure rise is too rapid.

What happens if there is more ignition delay?

If there is more ignition delay then engine is more prone to knocking. Delay period is basically the time gap between starting of mixing of air and fuel and the start of ignition. Physical Delay is the time taken for the air and fuel to mix with each other properly.

What is the difference between delay period and physical delay?

Delay period is basically the time gap between starting of mixing of air and fuel and the start of ignition. Physical Delay is the time taken for the air and fuel to mix with each other properly. Chemical delay is the time taken for the chemical reactions to take place till the time of start of ignition.