Answer:
the overall heat transfer coefficient of this heat exchanger is 1855.8923 W/m²°C
Explanation:
Given:
d₁ = diameter of the tube = 1 cm = 0.01 m
d₂ = diameter of the shell = 2.5 cm = 0.025 m
Refrigerant-134a
20°C is the temperature of water
h₁ = convection heat transfer coefficient = 4100 W/m² K
Water flows at a rate of 0.3 kg/s
Question: Determine the overall heat transfer coefficient of this heat exchanger, Q = ?
First at all, you need to get the properties of water at 20°C in tables:
k = 0.598 W/m°C
v = 1.004x10⁻⁶m²/s
Pr = 7.01
ρ = 998 kg/m³
Now, you need to calculate the velocity of the water that flows through the shell:
It is necessary to get the Reynold's number:
Like the Reynold's number is greater than 10000, the regime is turbulent. Now, the Nusselt's number:
The overall heat transfer coefficient:
Here
Substituting values:
Answer:
option e is correct answer
Properties of Carpenter's hammer possess
Explanation:
1.The head of a carpenter's hammer should possess the impact resistance, so that the chips do not peel off the striking face while working.
2.The hammer head should also be very hard, so that it does not deform while driving or eradicate any nails in wood.
3.Carpenter's hammer is used to impact smaller areas of an object.It can drive nails in the wood,can crush the rock and shape the metal.It is not suitable for heavy work.
How hammer head is manufactured :
1.Hammer head is produced by metal forging process.
2.In this process metal is heated and this molten metal is placed in the cavities said to be dies.
3.One die is fixed and another die is movable.Ram forces the two dies under the forces which gives the metal desired shape.
4.The third process is repeated for several times.
Answer:
Explanation:
Steam at outlet is an superheated steam, since 
. From steam tables, the specific enthalpy is:
The throttle valve is modelled after the First Law of Thermodynamics:
Hence, specific enthalpy at inlet is:
The quality in the steam line is:
