Re: Maintaining Capacity When The Conveying Length Is Increased
Originally Posted by Teus Tuinenburg
SLR = constant / Length^
Consequently, a longer pipeline with the same diameter and velocity and pressure drop results in a lower capacity.
It can also be proven that:
Diameter pipe = SQRT (Capacity* Length^/constant)
This formula implicates that, when a pipeline is lengthened and the pressure is maintained and the capacity is maintained, the pipe diameter must be increased.
The “scaling factor” is then:
D2 = D1 * SQRT (Length2^ / Length1^)
A conclusion of this exercise is that if the length of a pipeline is increased, the diameter of the pipeline must also be increased to maintain the capacity.
This indicates that the capacity of a pipeline is related to the volume of the pipeline, not only by the increased length, but also by the increased diameter.
This results in:
Volume longer pipe = (length longer pipe / length shorter pipe) ^ (1+ ) * Volume shorter pipe.
Rule of thumb: Higher capacity requires a higher volume of the conveying pipe.
This theory is applicable for both dense and dilute phase conveying system? ■
Re: Maintaining Capacity When The Conveying Length Is Increased
Dear chavannilesh,
Depends on your exact definition of dense and dilute phase pneumatic conveying. ■
Teus
Re: Maintaining Capacity When The Conveying Length Is Increased
Originally Posted by Teus TuinenburgDepends on your exact definition of dense and dilute phase pneumatic conveying.
Dear sir,
How you differntiate dense and dilute phase conveying.
How different theory can work for the both system. ■
Re: Maintaining Capacity When The Conveying Length Is Increased
Dear chavannilesh,
The mathematics do not work for conveying systems operating in the unstable region of the Zenz diagram and also not for plug conveying systems.
The "scaling" is valid for an approximation assessment of the new situation and only valid for the same capacity, the same pressure and the same velocities.
How you differentiate dense and dilute phase conveying.
How different theory can work for the both system.
It was you, who asked about the validity for dense- and/or dilute phase.
This assumes that you know the difference between dense- and/or dilute phase and you must at least know what you are asking for. ■
Teus
Re: Maintaining Capacity When The Conveying Length Is Increased
Originally Posted by Teus TuinenburgThe mathematics do not work for conveying systems operating in the unstable region of the Zenz diagram and also not for plug conveying systems.
The "scaling" is valid for an approximation assessment of the new situation and only valid for the same capacity, the same pressure and the same velocities.
It was you, who asked about the validity for dense- and/or dilute phase.
This assumes that you know the difference between dense- and/or dilute phase and you must at least know what you are asking for.
Actually we design dilute systems taking maximum SLR upto 3.
actually peoples are taking more than 3 SLR at the same time air flow is reduced and pressure is increased
For the same capacity.
I am not much familiar with design of dense phase conveying. ■
Re: Maintaining Capacity When The Conveying Length Is Increased
Dear chavannilesh,
Actually we design dilute systems taking maximum SLR up to 3.
actually peoples are taking more than 3 SLR at the same time air flow is reduced and pressure is increased
For the same capacity.
Of course, a system can be designed for an SLR of 3.
Such a system will work almost always and there is little chance that such a system fails.
This because the pressure drop for material acceleration and -losses is almost zero.
The air pressure drop is the dominant pressure drop, as you are mostly conveying air (or another gas).
The consequence is that the energy consumption per conveyed ton is very high.
(Far right in the Zenz diagram)
Certainly not an efficient design, resulting in high investment and high operation costs.
I am not much familiar with design of dense phase conveying.
Again, what do you consider as dense phase conveying? ■
Teus
Re: Maintaining Capacity When The Conveying Length Is Increased
Originally Posted by Teus TuinenburgOf course, a system can be designed for an SLR of 3.
Such a system will work almost always and there is little chance that such a system fails.
This because the pressure drop for material acceleration and -losses is almost zero.
The air pressure drop is the dominant pressure drop, as you are mostly conveying air (or another gas).
The consequence is that the energy consumption per conveyed ton is very high.
(Far right in the Zenz diagram)
Certainly not an efficient design, resulting in high investment and high operation costs.
Again, what do you consider as dense phase conveying?
When SLD is high with lower velocity and high pressure with material flow is plug type then we said dense phase. ■
Re: Maintaining Capacity When The Conveying Length Is Increased
Dear chavannilesh,
When SLR is high with lower velocity and high pressure with material flow is plug type then we said dense phase.
For sure, when the material flow is of the plug type, then it is dense phase, regardless the SLR, pressure, and velocity. ■
Teus
Maintaining capacity when the conveying length is increased
It can be proven that an increased pipeline allows a lower SLR for the same pressure and velocity.
SLR = constant / Length^
Consequently, a longer pipeline with the same diameter and velocity and pressure drop results in a lower capacity.
It can also be proven that:
Diameter pipe = SQRT (Capacity* Length^/constant)
This formula implicates that, when a pipeline is lengthened and the pressure is maintained and the capacity is maintained, the pipe diameter must be increased.
The “scaling factor” is then:
D2 = D1 * SQRT (Length2^ / Length1^)
A conclusion of this exercise is that if the length of a pipeline is increased, the diameter of the pipeline must also be increased to maintain the capacity.
This indicates that the capacity of a pipeline is related to the volume of the pipeline, not only by the increased length, but also by the increased diameter.
This results in:
Volume longer pipe = (length longer pipe / length shorter pipe) ^ (1+ ) * Volume shorter pipe.
Rule of thumb: Higher capacity requires a higher volume of the conveying pipe. ■
Teus