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Surface Phenomena
Published in Pramod K. Naik, Vacuum, 2018
The sticking probability st is defined as the probability of adsorption of an incident molecule on the surface. Measurement of s t is made by the measurement of sorption/pumping speed S of the surface and comparing it with conductance C 0 of an orifice of the equivalent size. Thus S st = C0 Several workers 18,19 have investigated the subject of sticking probability. Generally, the sticking probabilities vary between 0.1 and 1 and then fall as the monolayer coverage is approached. We have seen that number of molecules incident on unit area per second is given as follows by equation (1.9)
Wax deposition rate model for heat and mass coupling of piped waxy crude oil based on non-equilibrium thermodynamics
Published in Journal of Dispersion Science and Technology, 2018
Yang Liu, Chenlin Pan, Qinglin Cheng, Bing Wang, Xuxu Wang, Yifan Gan
Not all precipitated solid particles and the wax molecules that passed to the tube wall will attach to the tube wall. Some of the particles will be bounced back into the oil flow by object surface. There exists a “sticking probability,” which means the probability of attachment of particles on the object surface. Attachment process is determined by many factors, including wall condition, particle size, intermolecular force and flow rate, and so forth. When the particles that delivered to the tube wall are all attached to the wall, the deposition rate can be expressed as:
Nozzle zone agglomeration in spray dryers: Determination of the agglomeration efficiency in the fines return by means of agglomerate properties and residence time distribution
Published in Drying Technology, 2023
Jakob Alfons Fröhlich, Nora Alina Ruprecht, Reinhard Kohlus
However, the effect of an altered feed solids content on the agglomeration efficiency cannot exclusively be explained by the altered sticking probability. For example, increasing the solids content may decrease the sticking probability because the surface is less wet. However, if the particles stick less, more particles will not agglomerate and thus remain in the fines return, increasing the collision probability. Thus, decoupling of both possibilities is required to evaluate the effect of different process parameters. This decoupling by means of a literature model is aimed at in the following paragraph.