The good news is that there is no difference in the calculation of a vacuum conveying- and pressure conveying system.
The calculation of a pneumatic conveying system (vacuum or pressure) is based on the law of continuity of the air and material mass flow.
And the law of continuity is valid for both systems.
However, what is different, is that the air mass flow for a vacuum system is a function of the vacuum (variable) and for a pressure system the air mass flow is a function of the compressor intake pressure (approx. constant).
Both calculations start with the calculation of the air mass flow, based on the compressor.
(A vacuum pump is a compressor)
The consequence of this conclusion is that the ratio “material flow/gas flow” (Solid Loading Ratio) is the important variable to calculate and quantify a pneumatic conveying installation.
A vacuum calculation and a pressure calculation are both limited by the used pressure ratios and local suspension velocities, all governed by the same formulas.
Once you have a calculation algorithm for a pressure system, you have also a calculation algorithm for a vacuum system.
The above leads to the conclusion that pneumatic conveying is a mass conveying technology and NOT a volume conveying technology, like a belt conveyor. ■
Difference between the calculation of vacuum conveying and pressure conveying.
The good news is that there is no difference in the calculation of a vacuum conveying- and pressure conveying system.
The calculation of a pneumatic conveying system (vacuum or pressure) is based on the law of continuity of the air and material mass flow.
And the law of continuity is valid for both systems.
However, what is different, is that the air mass flow for a vacuum system is a function of the vacuum (variable) and for a pressure system the air mass flow is a function of the compressor intake pressure (approx. constant).
Both calculations start with the calculation of the air mass flow, based on the compressor.
(A vacuum pump is a compressor)
The consequence of this conclusion is that the ratio “material flow/gas flow” (Solid Loading Ratio) is the important variable to calculate and quantify a pneumatic conveying installation.
A vacuum calculation and a pressure calculation are both limited by the used pressure ratios and local suspension velocities, all governed by the same formulas.
Once you have a calculation algorithm for a pressure system, you have also a calculation algorithm for a vacuum system.
The above leads to the conclusion that pneumatic conveying is a mass conveying technology and NOT a volume conveying technology, like a belt conveyor. ■
Teus