Answer:
(a) The mass fractions of α and β phases
⇒ and
(b) The mass fractions of primary α and eutectic micro constituents.
primary α = 0.73 and eutectic micro constituents = 0.27
(c) The mass fraction of eutectic α. = 0.07
Explanation:
Answer:
give the question in English it'd be understandable
Answer:
- Fins should be attached outside the tube
- Fins can be attached on both sides when convection coefficient of air inside the tube is equal to the convection coefficient of atmospheric air outside the tube
Explanation:
The main function of the fins that are to be added is to ensure the speedy transfer of heat from the Hot air.
The fins should be attached outside the tube because the convection coefficient of air is higher inside the tube than the convection coefficient of the outside air ( atmospheric air ), BUT
When convection coefficient of air inside the tube is equal to the atmospheric air outside the tube, it is recommended that the fins can be added on both sides of the tube ( i.e. in and outside the tube )
Explanation:
Damkohler numbers are mainly used in chemistry. It is a dimensionless number. It denotes the timescale at which the reaction takes place with relation to the transport phenomenon.
There are two Damkohler numbers
First Damkohler number is the ratio of reaction rate to the convective mass transport rate.
Second Damkohler number is the ratio of reaction rate to the diffusive mass transfer rate
It can be seen from the equations that if the numerator is greater than the denominator then Da>1 and vice versa.
So,
When Da>1, the diffusion rate distribution is lower than the reaction rate.
When Da<1, the reaction rate is lower than the diffusion rate.