Adhesion of Dust to Obstacles in an Air Stream

Adhesion of Dust to Cylindrical and Spherical Surfaces. The number of particles of a given size deposited on an obstacle can be calculated from the equation 

In the present case, r o is the ratio of the number of adherent particles to the total number of particles passing across the midsection of the obstacle. The amount of adherent dust and the value of the capture coefficient will depend on the conditions of flow around the obstacle by the dust-laden stream, on the possibility of particle rebound from the surface, and on the adhesive forces capable of holding these particles. The capture coefficient will have a value less than unity. 

The capture coefficient is a quantity characterizing not only the conditions of flow around the surfaces by the dust-laden stream, but also the adhesion of particles to these surfaces. 

The coefficient Kq, in contrast to the capture coefficient 170, determines only the particle rebound it does not take any account of the conditions of flow around the surfaces. Hence the capture coefficient gives a more nearly complete characterization of particle adhesion for the flow around different obstacles. 

The values of the capture coefficient can be calculated in some cases or may be determined experimentally [255-257]. 

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