INFLUENCE OF THE MEASURING TOOLS ON THE FLOW CHARACTERISTICS IN VORTEX CHAMBER PUMP

Problem. Perturbation of the flow by measuring instruments forces researchers to choose optical research methods. But these methods significantly increase the cost of experimental research, due to the high cost of optical-type measuring equipment. On the other hand, using contact methods for measuring the flow velocity, such as Pitot tubes, hot-wire anemometers, the researcher must be sure that the measurement results can really be compared with the calculations results and the equipment influence on the flow parameters is minimal. The aim of this work is to study the measuring tool influence on the flow characteristics in the swirl chamber pump, as well as to compare the results obtained due to the measurements with the parameters of the undisturbed flow. The research methodology consisted of two stages: 1) modeling the flow in the model pump; 2) comparison of flow characteristics, as well as the values of velocity and pressure at the points of installation of the measuring tool. Results. Although the total velocity at the measuring point is practically independent of the measuring tool, the tangential component of the velocity is significantly reduced. It indicates that there is a significant error in velocity measuring. For a more accurate rotational velocity component measurement, it is necessary to orient the instrument perpendicular to the measured component. Scientific novelty. Installing the measuring tool in the end cover of the swirl chamber reduces the flow rate sucked by the pump through the lower axial channel. The size of the tool has practically no effect on the energy characteristics of the swirl chamber pump. Practical value. To ensure measurement accuracy, the ratio of the swirl chamber dimensions and the tool should be ensured in the way that the relative diameter of the tool does not exceed 0.25 of the swirl chamber neck diameter.

Flow fields of a non-Newtonian fluid in vortex chamber pumps

Problem. Pumping different fluids by hydraulic transport is associated with fast wear of the pump contact surfaces. The fluids being pumped are often non-Newtonian. The use of jet pumps for pumping is impractical due to low efficiency. Vortex chamber pumps may have higher efficiency when pumping non-Newtonian fluids, however, their operation on such fluids has not yet been studied. The aim of this work is to study the characteristics of the flow fields of a non-Newtonian fluid using the example of a Bingham fluid in the vortex chamber pump. Methodology. Predicting pump energy performance and determining flow fields for highly viscous fluids using CFD simulations enables advanced jet pumps to handle non-Newtonian fluids. Results. Modeling was carried out based on the numerical solution of the RANS equations with the SST turbulence model. To ensure the operability of the vortex chamber pump when pumping non-Newtonian fluid, with known rheological parameters of the mixture, it is necessary to select the required supply pressure for the active flow, and also to consider the issue of diluting the liquid with water to reduce the mixture viscosity and achieve the specified values of the pumping energy parameters. Originality. The hypothesis that the vortex chamber supercharger can operate on a hypothetical ideal fluid has been confirmed. In this case, the performance indicators of such a supercharger improve and tend to ideal. With an increase in plastic viscosity, the volumetric flow rate of the pumped fluid decreases, and at high values of the viscosity, an active flow is ejected through the axial channels. Practical value. Researchers can use the theoretical results of this work to design new devices for pumping other Bingham fluids, such as oil paint, resins, varnishes, swamp soils, and many others.

Pilot test results of GP-200/11x500-m stage chamber pump

The article reviews and analyses issues that include optimisation of pumping equipment for efficient drainage of saline water in conditions of underground mines. It describes approaches to design improvement of pumping equipment and shows the economic effect of its implementation based on the results of pilot tests.

MODELING THE INFLUENCE OF THE DESIGN OF THE AERATION DEVICE ON THE UNLOADING OF THE AIR PUMP

It is impossible to imagine the technological process of production of building materials, dry building mixes, reinforced concrete products without an important technological operation of transporting powder materials. Pneumatic chamber pumps are widely used for transporting powder bulk materials and are a mandatory element in the configuration of concrete plants and other mixing equipment. Their advantages are the possibility of full automation of work, reliable protection from atmospheric influences and the necessary sanitary and hygienic working conditions. Therefore, pneumatic chamber pumps are increasingly used for transportation. Compressed air is piped into the pump chamber. The bulk material is saturated with air, the resulting aerated mixture under the influence of excess pressure enters the pipeline and is transported in the specified direction. The disadvantage of pneumatic chamber pumps is the increased consumption of compressed air during transportation. To reduce air consumption, various aeration devices are used. Currently, at the modeling stage, modern software is used to determine the effectiveness of the developed aeration device. The influence of the air flow velocity on the discharge of a pneumatic chamber pump is considered. A design solution for the aeration device of the TA-29 pneumatic chamber pump is proposed.

Performance evaluation and comparison of a serial–parallel hybrid multichamber piezoelectric pump

To improve the output capability of piezoelectric pumps, researchers have made an attempt to combine multiple single-chamber pumps either in series or in parallel. In this article, a serial–parallel hybrid multichamber piezoelectric pump is presented. The novel serial–parallel hybrid multichamber piezoelectric pump structure is characterized by the simultaneous occurrence of serial/parallel forms through a combination of synchronous and asynchronous modes of piezoelectric actuators. Moreover, the pump can be operated in multiple working modes to obtain the desired chamber volume and number through different serial–parallel configurations. The performance characteristics of the pump with various serial–parallel hybrid combinations were experimentally investigated and evaluated using a quintuple-chamber pump at 90 V with a frequency range of 60–400 Hz. Experimental results showed that the characteristics in terms of flow rate and backpressure changed significantly with different serial–parallel modes. Nevertheless, the backpressure presented very similar characteristics for the serial–parallel hybrid multichamber piezoelectric pump with the same number of in-phase parallel actuators. Meanwhile, the frequency-dependent flow rate characteristics were approximately similar for those pumps with symmetric serial–parallel combinations. It was found that the flow rate and backpressure mainly depended on the actuation frequency and serial–parallel modes, respectively. Compared with the quintuple-chamber pump with full out-of-phase actuators, the maximum powers of the serial–parallel hybrid multichamber piezoelectric pump with two, three, four, and five in-phase actuators were decreased by 21.1%, 51.4%, 77.7%, and 94.4%, respectively.