Answer:
a) 2622.903 N/m^3
b) 1.38233
c)4.878811765
Explanation:
Find the void ratio using the formula:
Here;
is specific gravity of soil solids
is unit weight of water = 998 kg/m^3
is the moisture content = 0.17
is the void ratio
is the unit weight of soil = 14.9KN/m^3
Saturation Ratio Formula:
S is saturation rate
Substitute Eq 2 into Eq 1
Specific gravity of soil solids
Saturated Unit Weight
Solution :
Methods for selling pressure of a distillation column :
a). Set, the overhead stream using cooling water.
(minimum of approximate 45°C condenser temperature)
b). Set, of bottom product that avoids decomposition or reaction.
c). Set, not utility for reboiler.
Running the distillation column above the ambient pressure because :
The components to be distilled have very high vapor pressures and the temperature at which they can be condensed at or below the ambient pressure.
Run the reactor at an evaluated temperature because :
a). The rate of reaction is taster. This results in a small reactor or high phase conversion.
b). The reaction is endothermic and equilibrium limited increasing the temperature shifts the equilibrium to the right.
Run the reaction at an evaluated pressure because :
The reaction is gas phase and the concentration and hence the rate is increased as the pressure is increased. This results in a smaller reactor and /or higher reactor conversion.
The reaction is equilibrium limited and there are few products moles than react moles. As increase in pressure shifts the equilibrium to the right.
Answer:
a) What is the surface temperature, in °C, after 400 s?
T (0,400 sec) = 800°C
b) Yes, the surface temperature is greater than the ignition temperature of oak (400°C) after 400 s
c) What is the temperature, in °C, 1 mm from the surface after 400 s?
T (1 mm, 400 sec) = 798.35°C
Explanation:
oak initial Temperature = 25°C = 298 K
oak exposed to gas of temp = 800°C = 1073 K
h = 20 W/m².K
From the book, Oak properties are e=545kg/m³ k=0.19w/m.k Cp=2385J/kg.k
Assume: Volume = 1 m³, and from energy balance the heat transfer is an unsteady state.
From energy balance:
Initial temperature wall =
Surface temperature = T
Gas exposed temperature =