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What are the types of discretization methods?

Time: Explicit and Implicit

Spatial: Forward, Backward and Central Difference

What is explicit and implicit? Which one of these methods is more stable and

why?

Explicit methods calculate the state of a system at a later time from the state of the system at the

current time.

Implicit methods find a solution by solving an equation involving both the current state of the system

and the later one.

Implicit methods need extra computation and are harder to implement.

What are the coordinates of: Cartesian, cylinder, polar? 

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What is grey body, black body and define emissivity. Give value for emissivity

of a grey body.

 A grey  body  is a body with constant emissivity over all wavelengths and temperature.

 A black body  is an idealized physical body that absorbs all incident electromagnetic radiation.

Consider the following chemical reaction:

aA+bB -> cC+dD

Which chemical reaction rate and define the parameters?

Define the reaction rate constant ?

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What are types of heat models?

Which model is use for very high temperature and explain why

Which molecules...... radiation

The monte carlo models is used for very high temperature because it is used to trace beams in

furnace.

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Is it possible to solve the equation (Fundamental Fluid dynamic equations)

directly by analytical methods? If yes, how? If not, how can it be solved?

It is impossible that is why the Reynolds average Navier stoke equation is used to solve it.