Answer:
a) Mechanical efficiency (
)=63.15% b) Temperature rise= 0.028ºC
Explanation:
For the item a) you have to define the mechanical power introduced (Wmec) to the system and the power transferred to the water (Pw).
The power input (electric motor) is equal to the motor power multiplied by the efficiency. Thus, 
.
Then, the power transferred (Pw) to the fluid is equal to the flow rate (Q) multiplied by the pressure jump 
. So 
.
The efficiency is defined as the ratio between the output energy and the input energy. Then, the mechanical efficiency is 
For the b) item you have to consider that the inefficiency goes to the fluid as heat. So it is necessary to use the equation of the heat capacity but in a "flux" way. Calling <em>H</em> to the heat transfered to the fluid, the specif heat of the water and 
the density of the water:
![[tex]H=(5.7-3.6) kW=\rho*Q*c*\Delta T=1000kg/m^3*0.018m^3/s*4186J/(kg \ºC)*\Delta T](https://tex.z-dn.net/?f=%5Btex%5DH%3D%285.7-3.6%29%20kW%3D%5Crho%2AQ%2Ac%2A%5CDelta%20T%3D1000kg%2Fm%5E3%2A0.018m%5E3%2Fs%2A4186J%2F%28kg%20%5C%C2%BAC%29%2A%5CDelta%20T)
[/tex]
Finally, the temperature rise is:
Answer:
a) civil engineering.
Explanation:
Civil engineering is a professional engineering program that deals with the construction, design, and maintenance of all the natural and man-made environments including dams, buildings, railways, and roads.
Civil engineering is the branch of engineering that is the practice not restricted because civil engineer is not restricted to academic profession but practice in designing and construction can make someone a professional civil engineer.
Hence, the correct answer is "a)."
Answer:
During film condensation on a vertical plate, heat flux at the top will be higher since the thickness of the film at the top, and thus its thermal resistance, is lower.
Explanation:
https://www.docsity.com/pt/cengel-solution-heat-and-mass-transfer-2th-ed-heat-chap10-034/4868218/
https://arc.aiaa.org/doi/pdf/10.2514/1.43136
https://arxiv.org/ftp/arxiv/papers/1402/1402.5018.pdf
Answer:
a) V_2 = 82.1 m/s
b) m = 0.298 Kg/s
Explanation:
from A-11 to A-13 we have the following data
P_1 = 600 kpa
V_1 = 0.033925 m^3/kg
h_1 = 262.52 kJ/kg
P_2 = 700 kpa
V_2 = 0.0313 m^3/kg
T_2 = 40°C = 313K
h_2 = 278.66 kJ/kg
Now, from the conversation of mass,
A_2*V_2/u_2 = A_1*V_1/u_1
V_2 = A_1/A_2*u_2/u_1*V_1
V_2 = A_1/1.8*A_1 * 0.0313 /0.033925*160
V_2 = 82.1 m/s
now from the energy balance equation
E_in = E_out
Q_in + m(h_1 + V_1^2/2) = m(h_2 + V_2^2/2)
m = 0.298 Kg/s
Answer:
you might be facing some difficulty in observing this point of division between your question and me
