The equations are based on the following assumptions
1) The bar is straight and of uniform section
2) The material of the bar is has uniform properties.
3) The only loading is the applied torque which is applied normal to the axis of the bar.
4) The bar is stressed within its elastic limit.
Nomenclature
T = torque (Nm)
l = length of bar (m)
J = Polar moment of inertia.(Circular Sections) ( m^4)
J' = Polar moment of inertia.(Non circluar sections) ( m^4 )
K = Factor replacing J for non-circular sections.( m^4)
r = radial distance of point from center of section (m)
ro = radius of section OD (m)
τ = shear stress (N/m^2)
G Modulus of rigidity (N/m^2)
θ = angle of twist (radians)
Answer:
576.21kJ
Explanation:
#We know that:
The balance mass 
so, 
#Also, given the properties of water as;
#We assume constant properties for the steam at average temperatures:
#Replace known values in the equation above;
#Using the mass and energy balance relations;
#We have 
: we replace the known values in the equation as;
#Hence,the amount of heat transferred when the steam temperature reaches 500°C is 576.21kJ
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:
As the x-values go to negative infinity, the function’s values go to positive infinity.
Explanation:
if the ans choices are:
As the x-values go to negative infinity, the function’s values go to negative infinity.
As the x-values go to negative infinity, the function’s values go to positive infinity.
As the x-values go to positive infinity, the function’s values go to negative infinity.
As the x-values go to positive infinity, the function’s values go to zero.
the ans is the 2nd choice
