Answer Explanation:
CASCADE REFRIGERATION SYSTEMS :
cascade refrigeration systems are commonly used in the liquefaction of natural gas and some other gases
- cascade refrigeration system is also known as freezing system. It uses two types of refrigerants having different boiling points.
- this system is employed to obtain temperature of -40 to -80
- It allows stable ultra low temperature operation
examples of cascade refrigeration system: LNG (Liquefied natural gas ) plants mostly used cascade refrigeration system
ADVANTAGES OF CASCADE REFRIGERATION SYSTEMS:
- energy is saved because the system allows the use of refrigerant gases
- the running cost is inexpensive
- repair is easy
To solve the problem it is necessary to use the concepts related to frictional dissipation per unit mass, energy balance equation and Volumetric flow rate.
The frictional dissipation per unit mass is defined as
Where,
Superficial velocity of fluid
Fluid viscoisty
Porosity
Fluid density
L = Packed bed length
= Effective particle diameter
Through energy balance equation we have that
Neglect the change in velocity and pressure and the work done we have,
We have also that de grade is defined as
With our values and replacing at the previous equation we have,
Previously with the given depth and height we have to
Therefore the Volumetric flow rate,
Therefore the desired volumetric flow rate is 2456gal/min
Answer:
1/2
Explanation:
Lets take N is the speed of engine in RPM.
As we know that in two stroke engine ,crank rotates one times in two stroke of piston.Every rotation of crank gives one power stroke.It means that two stroke give one power stroke.
On the other hand in four stroke engine,crank rotates two times in 4 stroke of piston.It means that 4 stroke of piston gives one power stoke .
So we can say that the ratio of number of power stroke in two stroke engine to the number of power stroke in four stroke engine is 1/2.
A law stating that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature.
Hope it helps