METHOD OF THERMODYNAMIC DIAGNOSTICS FOR SOLID HYDRAULIC MACHINES OF CONSTRUCTION EXCAVATORS
Abstract and keywords
Abstract:
A method of thermodynamic diagnostics for solid hydraulic machines of construction excavators is presented. When working with solid hydraulic machines of construction excavators, the temperature of the working fluid increases, which can reduce the viscosity and efficiency of the system, as well as lead to component wear. It is shown that the method of thermodynamic diagnostics for solid hydraulic machines of construction excavators makes it possible to estimate energy losses, heat generation and the effect of temperature on the efficiency of the hydraulic drive system. Equations of the energy balance of a hydraulic pump with drainage and drainage-free mains are given. The results of modeling the thermophysical parameters of working fluids used in a hydraulic drive are obtained for known values of the thermophysical parameters of the fluid. The efficiency of solid hydraulic machines is determined depending on pressure and temperature differences. It is found that in the presence of undissolved gas in the hydraulic system, the hydrodynamic method for determining total efficiency provides a lower probability of rejection of serviceable hydraulic pumps than the method for diagnosing high volumetric efficiency. The higher the pressure drop and the lower the pump efficiency, the higher the measurement accuracy. The error in determining the total efficiency of a hydraulic pump by thermodynamic methods is influenced by the following factors: instability of the characteristics of the working fluid, the presence of undissolved gas in the working fluid, heat exchange between the hydraulic pump case and the environment. Recommendations are made to determine the efficiency of volumetric pumps in real-world operating conditions by measuring pressure and temperature differences.

Keywords:
thermodynamic method, temperature, efficiency, pump, balance
References

1. Baulin MN, Nemtinova DA, Obolonskaya EM, Obolonskaya OYu, Shoter PI. Computational study of fluid flow in a centrifugal pump in Ansys CFX medium. Pumps. Turbines. Systems. 2016;2(19):75-79.

2. Valyukhov SG, Kretinin AV. Mathematical modeling of hydrodynamic processes in the flow part of a centrifugal pump using neural network algorithms. Pumps. Turbines. Systems. 2016;3(20):53-59.

3. Kalan VA, Petrov VI, Tuzov VYu, Doronina NI. Design method of flow passages of sinking pumps. Pumps. Turbines. Systems. 2016;3(20):60-65.

4. Lombardo M. Ways to increase the efficiency of centrifugal pumps. Theoretical aspects and operational experience. Pumps. Turbines. Systems. 2015;4(17):34-42.

5. Chaburko PS, Lomakin VO, Kuleshova MS, Baulin MN. Complex optimization of the flow part of a glandless pump by LP-Tau search. Pumps. Turbines. Systems. 2016;1(18):55-61.

6. Kornyushenko SI. Fundamentals of volumetric hydraulic drive and its control: textbook. Moscow: INFRA-M; 2024.

7. Volkov GYu, Menikhov VI, Melikhov OI. Problems of numerical modeling of a compensatory hydraulic shock with two-fluid codes and a possible mechanism of pressure drop before a hydraulic shock. Proceedings of the 12th International Conference - School of Young Scientists, December 01-03, 2021: Waves and Vortices in Complex Media; Moscow: ISPO-print LLC; 2021.

8. Kvasnikov IA. Thermodynamics and statistical physics. Theory of equilibrium systems: Thermodynamics. 2 ed. Moscow: Editorial; 2002.

9. Lunev S, Nikitin AA, Kaizer YF. Comparative analysis of the dependence of the bulk elastic modules of the liquid on pressure and gas factor. Journal of Physics: Conference Series. Krasnoyarsk: Institute of Physics and IOP Publishing Limited; 2019. DOIhttps://doi.org/10.1088/1742-6596/1399/5/055083.

10. Crane Technical Paper 410, 2006 International Standard ISO 13709, 2007. Centrifugal Pumps for Petroleum, Petrochemical, and Natural Gas Industries. Geneva: International Organization for Standardization; 2007.

11. Garcia A, Brun K, Aparicio A. Case Study of Liquids Drop-Out in a Natural Gas Pipeline Network. Pipeline Simulation Interest Group, Galveston. Texas; 2009.

12. McKee RJ, Broerman E. Acoustics in Pumping Systems. Proceedings of the Twenty-Fifth International Pump Users Symposium, Turbomachinery Laboratory. Texas: Texas A&M University, College Station; 2009.

13. Mohitpour M, Golshan H, Alan M. Pipeline Design and Construction. New York: ASME Press; 2005.

14. Mohitpour M, Szabo J, Hardeveld T. Pipeline Operation & Maintenance – A Practical Approach. ASME Press, New York. 2005.

15. Santos SP. Availability and Risk Analysis Effects on Gas Pipeline Tariff Making. Seventh International Pipeline Conference. Calgary, Alberta; 2008.

16. Santos SP. Monte Carlo Simulation – A Key for a Feasible Pipeline Design. Pipeline Simulation Interest Group. Texas: Galveston; 2009.

17. Southwest Research Institute Applied Physics Division Staff. Controlling the Effects of Pulsations and Fluid Transients in Industrial Plants. SGA-PCRC Seminar. Texas: San Antonio; 1982.

Login or Create
* Forgot password?