Computer-aided design of industrial installations

The paper concerns the design of industrial installations using computer programs. It also contains a description of problems that must be solved by a constructor who designs industrial installations, their components and characteristics at different stages of industrial design

Control system of laboratory stand for gearbox and coupling testing

The scheme control system of a laboratory stand for gearbox and coupling testing, capable of fulfilling many miscellaneous requirements has been described in the paper. The innovative solution, as well as the benefits of the application, based on the Program Logic Controller, connected with electrical motor drives and a computer measurement system, have been described and depicted. Special features of the suggested solution, such as flexibility and ability to develop or adjust for another application, have been characterized

Design Optimization of a Hydrodynamic Brake with an Electrorheological Fluid

This article describes the design optimization of a hydrodynamic brake with an electrorheological fluid. The design optimization is performed on the basis of mathematical model of the brake geometry and the brake’s electrical circuit. The parameters of the mathematical models are selected based on experimental tests of the prototype brake. Six different objective functions are minimized during the design optimization. The functions are created taking into consideration the following factors: the braking torque, brake weight, electric power absorbed by the brake, and the torque rise time. The assumed design variables are: the number of blades and the radii (inner and outer) of the brake’s working space. The optimization calculations are performed for two design variables intervals. The first interval is defined taking into consideration the accuracy of the mathematical model. The second, narrower interval is assumed for the tested prototypical brake. On the basis of the optimization calculation results, general guidelines are presented for the optimization of the hydrodynamic brakes with an ER fluid. In addition, the possibilities of optimizing the prototype brake are determined

DISTRIBUITION OF MANHATTAN DISTANCE IN SQUARE AND TRIANGULAR LATTICES

Abstract. This paper presents exact formulas to find the number of Manhattan distances in square and triangular lattices (with the step δ = 1) as a function of number of nodes, L. In the limit of L ∞ → and δ → 0, we provide probability density functions for distances in unit squares and triangles. These formulas are useful in the fields of statistical physics and computer science

Application of Plant Oils as Ecologically Friendly Hydraulic Fluids

This paper presents the results of physicochemical and tribological tests of vegetable oils obtained by the supercritical fluid extraction method from berry seeds. The research was conducted by using these oils as the raw material for the biodegradable hydraulic working fluids. The oils were assessed in terms of kinematic viscosity, anti-wear properties, resistance to oxidation and corrosive effects to copper and the pour point. The best results were achieved in the case of the blackcurrant seed oil. In order to confirm the practical possibility of using vegetable oils as working fluids for hydraulic couplings, experimental tests of the hydrodynamic clutch filled with blackcurrant seed oil were carried out. Based on the obtained research results, it was found that oils from berry plant seeds produced by supercritical extraction could be used in the future as potential working fluids for hydraulic systems

Modelling of Drive System Operation of a Wind Power Plant

The article presents experimental and theoretical studies concerning the possibility of using a controlled hydrodynamic clutch in a wind power plant’s drive system. The hydrodynamic clutch is controlled by changing the distance between the hydrodynamic clutch rotors. The control system is supposed to maintain a constant angular velocity of the electric generator shaft. The considered method of control has not been used so far in power plant's drive systems. The advantages of using a controlled hydrodynamic clutch is simple structure, high durability and low weight of the entire drive system. The equations of the mathematical model for the drive system are formulated on the basis of: the balance of torques and the equations of the hydrodynamic clutch with retractable rotors. The equations are based on the one-dimensional flow of the working fluid along the mean line of the stream. The model calculations are conducted numerically. In order to be able to determine the coefficients of the mathematical model, experimental research is conducted on a test bench designed specifically for this purpose. The research determines how the rotation direction and size of the gap between rotors influences the torque transferred by the hydrodynamic clutch, for selected values of the clutch’s filling degree and the working fluid’s temperature. On the basis of the model calculations results it was determined that a hydrodynamic clutch controlled by increasing the distance between rotors may be successfully used in drive systems of wind power plants to maintain a constant angular velocity of the electric generator shaft