What are the factors that affect flame speed?

Flame speed increases with an increase in intake temperature and pressure. A higher initial pressure and temperature may help to form a better homogeneous air-vapour mixture which helps in increasing the flame speed. This is possible because of an overall increase in the density of the charge.

What are the various factors that affect the flame speed explain any 3 with justification?

The temperature and pressure of the fuel/air mixture, ❑ The concentration of residuals , ❑ The chemical reaction rate.

What factors influence flame height?

The flame height is between 0.254 [m] and 1.5 (mn). Interior finish in a room, fuel continuity, feedback, material ignitability, thermal inertia of the fuel, proximity of flames to walls are the major factors that influence fire growth.

What is flame speed of natural gas?

The laminar flame speeds of hydrogen/air mixture and natural gas/air mixture reach their maximum values 2.933 and 0.374 m/s when equivalence ratios equal to 1.7 and 1.1, respectively.

What is the flame speed of propane?

These values agree quite well with the recent results of Strehlow & Stuart (1953), who measured the flame speed of propane/air mixtures by means of an improved soap-bubble method. They reported a flame speed of 40*4 ± 0-5 cm/s for q = 4-03 \%.

What is delay period and what are the factors that 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 are the factors affecting knocking in SI engine?

Factors affecting Detonation or Knocking in SI engine:

• Compression ratio: The pressure and temperature at the end of compression increases with increase in compression ratio.
• Supercharging:
• Increasing inlet temperature:
• Increase in load:
• Advancing the spark:
• Flame travel distance:
• Spark plug location:
• Engine size:

What are the 7 factors that affect fire development?

SOIL HEATING, TEMPERATURE, AND TRANSFER. Rate of burning and heat output for surface and crown fires are influenced by fuel load, fuel moisture, topography, ignition method, air temperature, wind, and relative humidity.

What are the 4 main factors influencing fire spread?

Fire spread depends on the principal methods of heat transfer: conduction, convection, radiation and direct burning.

What is fire speed?

The flame speed is the measured rate of expansion of the flame front in a combustion reaction. The flame is generally propagated spherically and the radial flame propagation velocity is defined as the flame speed. Flame speed is typically measured in m/s, cm/s, etc.

How does the flame speed affect the performance of combustion chamber?

The higher the flame speed is, the closer is the overall combustion process to the TDC, resulting in higher average temperature and pressure.

What factors affect the flame propagation speed of a flame?

Flame propagation speed increase with an increase in intake temperature and pressure. Higher intake pressure and temperature help to form better homogeneous fuel-air mixture. It also increases the density of the mixture, which increases flame speed. Flame speed is high in the turbulent mixture than the non-turbulent mixture.

What is the effect of engine speed on flame speed?

Increase in Engine speed increases the turbulence of charge inside the combustion chamber. The flame speed is also almost linearly increase with the increase in engine speed. When the engine speed doubled, the flame speed also doubled; in other words, the time taken for the complete combustion is halved.

How do you increase the speed of a flame?

A higher initial pressure and temperature may help to form a better homogeneous air-vapour mixture which helps in increasing the flame speed. This is possible because of an overall increase in the density of the charge.

Why does the flame speed increase with increase in turbulence?

The flame speed is quite low in non-turbulent mixtures and increases with increasing turbulence. This is mainly due to the additional physical intermingling of the burning and unburned particles at the flame front which expedites reaction by increasing’ the rate of contact.