Effect of undissolved gas on fluid bulk modulus

This document describes the effect of undissolved gas on the bulk modulus of the fluid. The concept of liquid compressibility and dependence on composition, temperature and pressure is considered. Various methods of measuring the modulus of volumetric elasticity of the liquid were considered. It was also proposed to improve the mathematical model for calculating the module of volumetric elasticity of a liquid. The results of the study were used to plot the effect of the gas phase content modulus of volumetric elasticity of working fluid at different pressures. It was also concluded that the obtained values describe the need to equip hydraulic drives with devices for degassing working liquids

Pump jack balancing control method depending on the load

This article focuses on the method of balancing the pump jack and optimizing its operation. In the course of the work, the main balancing methods were considered and a method based on changing the balancing value by moving the movable carriage was proposed. In the course of the work, a model was developed that made it possible to simulate loads, the results of which determined the effectiveness of the proposed balancing method. Based on the results of the study, a graph of the change in torque when the support is located during the operation of the drive was built. Based on the results of the work, the corresponding conclusion was made

The impact of seasonal changes in stratification on the dynamics of internal waves in the Sea of Okhotsk

The properties and dynamics of internal waves in the ocean crucially depend on the vertical structure of water masses. We present detailed analysis of the impact of spatial and seasonal variations in the density-driven stratification in the Sea of Okhotsk on the properties of the classic kinematic and nonlinear parameters of internal waves in this water body. The resulting maps of the phase speed of long internal waves and coefficients at various terms of the underlying Gardner’s equation make it possible to rapidly determine the main properties of internal solitary waves in the region and to choose an adequate set of parameters of the relevant numerical models. It is shown that the phase speed of long internal waves almost does not depend on the particular season. The coefficient at the quadratic term of the underlying evolution equation is predominantly negative in summer and winter and therefore internal solitons usually have negative polarity. Numerical simulations of the formation of internal solitons and solibores indicate that seasonal variations in the coefficient at the cubic term of Gardner’s equation lead to substantial variations in the shape of solibores