Answer:
T(water)=50.32℃
T(air)=3052.6℃
Explanation:
Hello!
To solve this problem we must use the equation that defines the transfer of heat by convection, which consists of the transport of heat through fluids in this case water and air.
The equation is as follows!
Q = heat
h = heat transfer coefficient
Ts = surface temperature
T = fluid temperature
a = heat transfer area
The surface area of a cylinder is calculated as follows
Where
D=diameter=20mm=0.02m
L=leght=200mm)0.2m
solving
For water
Q=2Kw=2000W
h=5000W/m2K
a=0.01319m^2
Tα=20C
solving for ts
for air
Q=2Kw=2000W
h=50W/m2K
a=0.01319m^2
Tα=20C
Answer:
12.332 KW
The positive sign indicates work done by the system ( Turbine )
Explanation:
Stagnation pressure( P1 ) = 900 kPa
Stagnation temperature ( T1 ) = 658K
Expanded stagnation pressure ( P2 ) = 100 kPa
Expansion process is Isentropic, also assume steady state condition
mass flow rate ( m ) = 0.04 kg/s
<u>Calculate the Turbine power </u>
Assuming a steady state condition
( p1 / p2 )^(r-1/r) = ( T1 / T2 )
= (900 / 100)^(1.4-1/1.4) = ( 658 / T2 )
= ( 9 )^0.285 = 658 / T2
∴ T2 = 351.22 K
Finally Turbine Power / power developed can be calculated as
Wt = mCp ( T1 - T2 )
= 0.04 * 1.005 ( 658 - 351.22 )
= 12.332 KW
The positive sign indicates work done by the system ( Turbine )
Answer:
a. 4
b. 1 m
Explanation:
According to the question, the data is as follows
The Density of water at 20 degrees celcius is 1000 kg/m^3
Viscosity is 0.001kg/m/.s
Velocity V = 25 cm/s
V = 0.25 m/s
Now
a. The creeping motion is
As we know that
Reynold Number = (Density of water × V × d) ÷ (Viscosity)
1 = (1,000 × 0.25 × d) ÷ 0.0001
d = (1 × 0.001) ÷ (1,000 × 0.25)
= 4E - 06^m
= 4
b. Now the sphere diameter is
Reynold Number = (Density of water × V × d) ÷ (Viscosity)
250,000 = (1,000 × 0.25 × d) ÷ 0.0001
d = (250,000 × 0.001) ÷ (1,000 × 0.25)
= 1 m
