Simulation of processing the “Power” composition in a mixer with oval rotors

The main dependence for determining the energy-power parameters of processing the compositions, whose behavior under load is described by a power rheological law in the operation gap of mixers with oval rotors. In the proposed method of calculating the power of the mixer drive motor an attempt was made to account for movement of a treated material not only in circular but also in the axial direction of the mixing chamber. These dependences for determining the pressure and power supplied to the rotors for rotation thereof may be recommended for engineering calculations of mixing equipment for plastics and rubber mixtures.     

Simulation of liquid cooling of an extruded sleeve plastic film

A mathematical model of a liquid cooling was considered for a tubular plastic film produced by extrusion down. The developed model allows for a preset film speed (extruder) and film parameters to determine a length of a cooling zone or for a preset length of the cooling zone calculation of maximum speed of the film with the preset parameters.     

Technique of parametric and heat computations of rollers for processing of plastics and rubber compounds

The technique of parametric and thermal simulation of rollers of continuous operation was developed for processing material whose behavior under load is described by a power rheological law. The technique is suitable for analyzing the process of rolling in the case of rollers with the same diameter, arbitrary frictions in a roll space, and also placing of rolled material in a low-speed as well as in a high-speed rollers.     

Simulation of disk extruder operation

Mathematical simulation of thermoplastic polymer processing by a disk extruder was considered. The results were compared with experimental data obtained in an extruder of a 200 mm diameter. The developed technique of calculation allows selection of design parameters of operational parts and disk speed for preset output of the disk extruder as well as energy-power parameters of extrusion.     

Classification of nozzles of mass transfer apparatuses

The detailed classification of nozzles of heat and mass transfer apparatuses is proposed. Examples of the constructive design of new types of domestic and foreign disordered and ordered nozzles are given.     

Pretreatment of recycled polymer raw material

The analysis of main methods and equipment for physical utilization (recycling) of polymer waste is performed. Main stages of the recycling as storage of waste, transportation, crushing and grinding, fractionation, sorting, washing, dehydration, agglomeration, and granulation are considered in detail.     

Screw extrusion of thermoplastics: II. Simulation of feeding zone of the single screw extruder

The technique of calculation of a feeding zone for a single screw extruder is developed taking into account the nonisothermal process and the actual boundary geometric conditions and speed conditions (the screw is rotated, the cylinder is fixed). An analysis of the influence of the screw geometry was performed and also of an effect of a ratio of friction coefficients of the processed material on the cylinder and worm, on a change in pressure and temperature of the processed material along the length of the feeding zone.     

Heat exchange in granulating thermoplastics

Cooling of polymer granules and strands in air and water was examined. The greatest effect of a turbulence of air flow on the cooling rate of granules was revealed in the starting period. An analysis of the cooling of granules in water demonstrated that the rate of heat transfer from a volume of thermoplastic material to its surface was a rate-limiting step and, thus, an effect of turbulization of a water flow on the cooling was negligible. We showed that it would be appropriate to install partitions destroying a heated boundary layer of water for intensifying process in a cooling bath since an actual cooling of the strands in the water bath longer corresponds to the case when water moves together with strand.     

Screw extrusion of thermoplastics: I. General model of the screw extrusion

New approach to a simulation of single and twin screw extruders for thermoplastics processing was suggested. The approach takes into account real boundary geometric conditions and conditions on velocity (a screw is rotated, cylinder is fixed), and also that there exist phase transformations of the processed material and its heat exchange with surfaces of the screw and cylinder limiting the working channel of the extruder.     

Modeling of the heat processing of continuously molded product

The mathematical models of heat processing (heating and cooling) of materials, semi-products and products, including multilayer produced by continuous molding, in particular, by extrusion and calendering are considered. The proposed models allows selection of main sizes of devices of the heat processing line for a preset output or determination of a maximum capacity of the line for given sizes of these devices.