Answer:
See explanation
Explanation:
Solution:-
- The shell and tube heat exchanger are designated by the order of tube and shell passes.
- A single tube pass: The fluid enters from inlet, exchange of heat, the fluid exits.
- A multiple tube pass: The fluid enters from inlet, exchange of heat, U bend of the fluid, exchange of heat, .... ( nth order of pass ), and then exits.
- By increasing the number of passes we have increased the "retention time" of a specific volume of tube fluid; hence, providing sufficient time for the fluid to exchange heat with the shell fluid.
- By making more U-turns we are allowing greater length for the fluid flow to develop with " constriction and turns " into turbulence. This turbulence usually at the final passes allows mixing of fluid and increases the heat transfer coefficient by:
U ∝ v^( 0.8 ) .... ( turbulence )
- The higher the velocity of the fluids the greater the heat transfer coefficient. The increase in the heat transfer coefficient will allow less heat energy carried by either of the fluids to be wasted ; hence, reduced losses.
Thereby, increases the thermal efficiency of the heat exchanger ( higher NTU units ).
Answer:
the pressure at a closed valve attached to the tank 10 ft above its bottom is 37.88 psi
Explanation:
Given that;
depth 1 = 71 ft
depth 2 = 10 ft
pressure p = 17 psi = 2448 lb/ft²
depth h = 71 ft - 10 ft = 61 ft
we know that;
p = P_air + yh
where y is the specific weight of ethyl alcohol ( 49.3 lb/ft³ )
so we substitute;
p = 2448 + ( 49.3 × 61 )
= 2448 + 3007.3
= 5455.3 lb/ft³
= 37.88 psi
Therefore, the pressure at a closed valve attached to the tank 10 ft above its bottom is 37.88 psi
The forklift overturning is a very common way of getting injured from a forklift. Overturning the forklift means it tips over onto it's side due to the operator turning it too fast.
Answer:
2.0%
Explanation:
Percentage of aggregate = 94%
Specific gravity = 2.65
Specific gravity of asphalt = 1.9
Density of mix = 147pcf = 147lb/ft³
Total weight of mix: (volume = 1ft³)
= (147lb/ft³)(1ft³)
= 147lb
Percentage weight of asphalt in<u> mix:</u>
100% - 94%
= 6%
Weight of asphalt binders
= 6% x 147lb
= 8.82lb
Weight of aggregate in mix:
= 94% x 147
= 138.18lb
Specific weight of asphalt binder:
(Gab)(Yw)
Yw = specific Weight of water
= 62.4lb
Gab = specific gravity of asphalt binder
= 1.0
(62.4lb)(1.0)
= 62.4 lb/ft³
Volume of asphalt in binder:
8.82/62.4
= 0.14ft³
Specific weight of binder in mix:
2.65 x 62.4lb/ft³
= 165.36 lb/ft³
Volume of aggregate:
= 138.18/165.36
= 0.84ft³
Volume of void in the mix:
1ft³ - 0.84ft³ - 0.14ft³
= 0.02ft³
<u>The percentage of void in total mix:</u>
VTM = (0.02ft³/1ft³)100
= 2.0%
