Abstract:An optimal way to select parameters of a driver’s seat of a special vehicle, which contributes directly to an increase in driving comfort is presented in the work. A mathematical model of the vehicle was formulated by using of joint coordinates and homogenous transformations. A maneuver of driving over obstacles in a form of a speed bump of different heights and lengths is presented. A subject of the investigations was to select such damping parameters and driver’s seat stiffness to minimize amplitudes of vibrations present in this subassembly. An influence of a form of an objective function and a selection of decisive variables on quality of the optimization results obtained was analyzed.
Abstract:A method of calculating the apparatus of combined action for carrying out a high-temperature reaction in a fluidised bed of the solid reactant particles is proposed based on a system approach. In this bed, the reaction proceeds simultaneously with the continuous grinding of the formed products and the processes of heat and mass transfer are significantly intensified in connection with the constant renewal (denudation) of the reaction surface both due to the impact fracture of the product shell in the zones of the intensive collision in the counterflows of the reacting particles and its abrasion in the body of the fluidised bed.
Abstract:In areas with scattered buildings and a low population density, the sewage management infrastructure is underdeveloped. Until recently, the only practical solution was to make a non-effluent and tight tank: a septic tank, which was one of the means to carry sewage away from detached houses in areas without sewage systems. Currently, domestic sewage treatment plants are highly popular. The paper shows the operating principle of a septic tank and a domestic treatment plant and analyses their advantages and disadvantages. Particular attention was paid to the economical aspect.
Abstract:This paper presents several ways of calculating real and theoretical energy efficiency coefficients of vapour compression heat pumps in short and long time. Differences in the calculation are associated with taking into account, among others, various components of the heat pump responsible for the consumption of electricity, steady state or transient conditions, part or the nominal load ratio of heat pump. The calculation results are compared with the values of coefficients, which have been obtained theoretically.
Nikiforova, Tatiana, Natareevv, Sergey, Kozlov, Vladimir
Type: Article
Release date:
2017
Abstract:An investigation of sorption kinetics of heavy metal ions on polysaccharide materials has been performed. Traditionally, kinetic study of ion exchange sorption begins with a determination of the slowest stage of the proces, but the stage of chemical reaction between heavy metal ions and the sorbent functional groups can also make essential contribution. Results of kinetic studies were treated using different kinetic models and, experimental data are described most adequately with pseudo-second order kinetic model. It is determined that polysaccharide materials used in the studies have relatively good kinetic characteristics.
Abstract:The paper presents the results of experimental studies of the enhancement of the boiling process of a zeotropic agent with high temperature glide inside tubes at a low heat flux density. It discusses the effect of three types of inserts on the heat transfer process and the flow resistances during boiling of R407C in vertical tubes. The experimental studies covered measurements of heat transfer coefficient values, flow resistance values and thermal efficiency in the measurement section.
Abstract:The study evaluated the impact of emissions (VOCs) as a result of the operation of the printing of plant at working positions of those performing their tasks outdoors or in buildings next door to the subject of the printing installation (offset printing). The first part of the paper presents the general characteristics of the process and materials used for printing. The further part shows the results of the modelling of emissions, depending on the operating state of purification (emission in normal conditions and emission conditions, which deviate from normal – failure state of the afterburner).
Abstract:Critical impeller rotational speeds for having a solid suspension in a liquid and for gas dispersion in the slim vessel with two independently driven impellers were determined. An A-315 impeller functioned as the lower impeller whereas a Rushton turbine was fixed higher with gas being fed right below the latter. We investigated what influence on this rotational speed was had by the distance between the impellers, their rotational direction, solid concentration, solid particle size and gas flow rate. Results obtained for the twoand three-phase systems were compared. In the three-phase systems, we also measured the power input in order to assess the efficiency of mixing.
Abstract:Our developed cell model of the mass transfer for the computation and prediction output parameters in a roll dewatering process of fibre materials by distributed pressure are presented. The model makes it possible to determine relationships between residual moisture content of fibre material and input parameters of the dewatering process.
Abstract:The thesis presents the analysis of the pneumatic tube system, one of the solutions in material handling. Contemporary solution components of pneumatic tube systems were presented and described, such as: blowers, diverters, send/receive stations, carriers, air brakes and system couplers. For the purpose of the article, a bypass air brake was built at the Laboratory of Techno-Climatic Research and Heavy Duty Machines of the Cracow University of Technology., which was then tested. The aim of the test was to determine the minor loss coefficient ζ, depending on the degree of the air brake valve override. The measurement results are given in the work.
