An Experimental Study Into The Effect Of Temperature And Pressure on The Hydraulic System

Abstract

The present work is conducted in order to study the effect of oil temperature and pressure variation on the hydraulic system performance at various ranges of temperature and pressure. The oil is the first component which will be influenced by the changes in the surrounding conditions and all its properties will be changed. The most important property of the oil that will be studied is the viscosity. The viscosity is measured experimentally at different temperatures (20 → 100) °C and atmospheric pressure and by using correlations taken from literature of other researchers in order to evaluate the viscosity at different temperatures and pressures. The hydraulic test bench existing at the Fluid Mechanic Laboratory/University of Technology has been developed to meet the requirements of the experimental work. The effect of the temperature and pressure will be studied by evaluating the work of two loading actuators (hydraulic cylinder and motor). It was found that, the oil viscosity depends mainly on the temperature and the effect of pressure on the viscosity can be noticed clearly at low temperature. The temperature rising in the closed hydraulic circuit is faster and higher than that in the open hydraulic circuit and the work of the system depends mainly on the temperature and the working period. Keywords: Hydraulic system, oil viscosity, temperature effect. ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴ‬ ‫ﺍﻟﻤﻨﻅﻭﻤﺔ‬ ‫ﻋﻠﻰ‬ ‫ﻭﺍﻟﻀﻐﻁ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺔ‬ ‫ﺘﺄﺜﻴﺭ‬ ‫ﻓﻲ‬ ‫ﺍﻟﻌﻤﻠﻴﺔ‬ ‫ﺍﻟﺩﺭﺍﺴﺔ‬ ‫ﺔ‬ ‫ﺍﻟﺨﻼﺼﺔ‬ ‫ﺍﺩﺍﺀ‬ ‫ﻋﻠﻰ‬ ‫ﺍﻟﻀﻐﻁ‬ ‫ﻭﺘﻐﻴﺭ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺔ‬ ‫ﺘﺄﺜﻴﺭ‬ ‫ﺩﺭﺍﺴﺔ‬ ‫ﻫﻭ‬ ‫ﺍﻟﺒﺤﺙ‬ ‫ﻫﺫﺍ‬ ‫ﻤﻥ‬ ‫ﺍﻷﺴﺎﺴﻴﺔ‬ ‫ﺍﻟﻐﺎﻴﺔ‬ ‫ﻭﺍﻟﻀﻐﻁ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺎﺕ‬ ‫ﻤﻥ‬ ‫ﻤﺘﻐﻴﺭ‬ ‫ﻟﻤﺩﻯ‬ ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴﺔ‬ ‫ﺍﻟﻤﻨﻅﻭﻤﺔ‬. ‫ﻫـﺫﻩ‬ ‫ﻓﻲ‬ ‫ﺘﻨﺎﻭﻟﻪ‬ ‫ﺘﻡ‬ ‫ﺘﺄﺜﻴﺭ‬ ‫ﺃﻭل‬ ‫ﺘﺄ‬ ‫ﻫﻭ‬ ‫ﺍﻟﺩﺭﺍﺴﺔ‬ ‫ﺍﻟﻤﻨﻅﻭﻤـﺔ‬ ‫ﻓـﻲ‬ ‫ﺍﻟﻤـﺴﺘﺨﺩﻡ‬ ‫ﺍﻟﺯﻴـﺕ‬ ‫ﻋﻠـﻰ‬ ‫ﻭﺍﻟـﻀﻐﻁ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺎﺕ‬ ‫ﺘﻐﻴﻴﺭ‬ ‫ﺜﻴﺭ‬ ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴﺔ‬ , ‫ﺨﻭﺍﺼﻪ‬ ‫ﺠﻤﻴﻊ‬ ‫ﻭﺘﺘﻐﻴﺭ‬ ‫ﺍﻟﻤﺤﻴﻁﻴﺔ‬ ‫ﺒﺎﻟﻤﺘﻐﻴﺭﺍﺕ‬ ‫ﻴﺘﺄﺜﺭ‬ ‫ﻤﻥ‬ ‫ﺃﻭل‬ ‫ﻫﻭ‬ ‫ﺍﻟﺯﻴﺕ‬ ‫ﺇﻥ‬ ‫ﺤﻴﺙ‬. ‫ﻤﻥ‬ ‫ﺍﻟﻠﺯﻭﺠـﺔ‬ ‫ﻫـﻲ‬ ‫ﺍﻟﻤـﺴﺘﺨﺩﻡ‬ ‫ﺒﺎﻟﺯﻴـﺕ‬ ‫ﺍﻟﻤﺘﻌﻠﻘﺔ‬ ‫ﺍﻟﺒﺤﺙ‬ ‫ﻫﺫﺍ‬ ‫ﻓﻲ‬ ‫ﺇﻟﻴﻬﺎ‬ ‫ﺍﻟﺘﻁﺭﻕ‬ ‫ﺘﻡ‬ ‫ﺍﻟﺘﻲ‬ ‫ﺍﻟﺨﻭﺍﺹ‬ ‫ﺃﻫﻡ‬ (Viscosity). ‫ﺍﻟﻠﺯﻭ‬ ‫ﻗﻴﺎﺱ‬ ‫ﺘﻡ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺎﺕ‬ ‫ﻤﻥ‬ ‫ﻤﺘﻐﻴﺭ‬ ‫ﻟﻤﺩﻯ‬ ‫ﻋﻤﻠﻴﺎ‬ ‫ﺠﺔ‬ (20 → 100)°C ‫ﻭﻋﻨـﺩ‬ ‫ﺍﻟﺠﻭﻱ‬ ‫ﺍﻟﻀﻐﻁ‬ , ‫ﻤﻥ‬ ‫ﺍﻟﻌﻼﻗﺎﺕ‬ ‫ﺒﺎﺴﺘﺨﺩﺍﻡ‬ ‫ﻤﺨﺘﻠﻔﺔ‬ ‫ﻭﻀﻐﻭﻁ‬ ‫ﺤﺭﺍﺭﺓ‬ ‫ﻟﺩﺭﺠﺎﺕ‬ ‫ﺍﻟﻠﺯﻭﺠﺔ‬ ‫ﻗﻴﻡ‬ ‫ﺤﺴﺎﺏ‬ ‫ﻭﺘﻡ‬ ‫ﺍﻟﺴﺎﺒﻘﺔ‬ ‫ﺍﻟﺒﺤﻭﺙ‬. ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜ‬ ‫ﺍﻟﻔﺤﺹ‬ ‫ﻤﻨﺼﺔ‬ ‫ﺘﻁﻭﻴﺭ‬ ‫ﺘﻡ‬ ‫ﻲ‬ ‫ﺍﻟﻤﻭﺍﺌـﻊ‬ ‫ﻤﺨﺘﺒـﺭ‬ ‫ﻓﻲ‬ ‫ﺍﻟﻤﻭﺠﻭﺩﺓ‬ / ‫ﺍﻟﺠﺎﻤﻌـﺔ‬ ‫ﺍﻟﺘﺠﺎﺭﺏ‬ ‫ﻤﻥ‬ ‫ﻤﺠﻤﻭﻋﺔ‬ ‫ﻹﺠﺭﺍﺀ‬ ‫ﺍﻟﺘﻜﻨﻭﻟﻭﺠﻴﺔ‬ ‫ﺃﻋﻼﻩ‬ ‫ﻟﻠﻐﺭﺽ‬. ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴﺔ‬ ‫ﺍﻟﻤﻨﻅﻭﻤﺔ‬ ‫ﺸﻐل‬ ‫ﺩﺭﺍﺴﺔ‬ ‫ﺘﻡ‬ ‫ﺍﻟﻤﺸﻐﻼﺕ‬ ‫ﻤﻥ‬ ‫ﻨﻭﻋﻴﻥ‬ ‫ﺃﺩﺍﺀ‬ ‫ﺒﺘﻘﻴﻴﻡ‬ (Actuators)) ‫ﻫﻴﺩﺭﻭﻟﻴﻜﻲ‬ ‫ﻭﻤﺤﺭﻙ‬ ‫ﺍﺴﻁﻭﺍﻨﺔ‬. (‫ﺍﻟﺘﻭﺼـل‬ ‫ﺘﻡ‬ ‫ﻟﻘﺩ‬ ‫ﻴﻜـﻭﻥ‬ ‫ﺍﻟﻠﺯﻭﺠـﺔ‬ ‫ﻋﻠﻰ‬ ‫ﺍﻟﻀﻐﻁ‬ ‫ﺘﺄﺜﻴﺭ‬ ‫ﻭﺍﻥ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺔ‬ ‫ﻋﻠﻰ‬ ‫ﻜﺒﻴﺭ‬ ‫ﺒﺸﻜل‬ ‫ﺘﻌﺘﻤﺩ‬ ‫ﺍﻟﻠﺯﻭﺠﺔ‬ ‫ﺇﻥ‬ ‫ﺇﻟﻰ‬ ‫ﺍﻟﻭﺍﻁﺌﺔ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺎﺕ‬ ‫ﻋﻨﺩ‬ ‫ﻭﺍﻀﺤﺎ‬. ‫ﺍﺭﺘﻔﺎ‬ ‫ﺇﻥ‬ ‫ﺍﻟﻤﻐﻠﻘـﺔ‬ ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴﺔ‬ ‫ﺍﻟﺩﺍﺌﺭﺓ‬ ‫ﻓﻲ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺔ‬ ‫ﻉ‬ PDF created with pdfFactory Pro trial version www.pdffactory.com An Experimental Study into the Effect of Temperature and Pressure on the Hydraulic System 2532 (Closed Hydraulic Circuit) ‫ﺍﻟﻤﻔﺘﻭﺤـﺔ‬ ‫ﺍﻟﻬﻴﺩﺭﻭﻟﻴﻜﻴـﺔ‬ ‫ﺍﻟﺩﺍﺌﺭﺓ‬ ‫ﻤﻥ‬ ‫ﻭﺃﻋﻠﻰ‬ ‫ﺃﺴﺭﻉ‬ ‫ﻴﻜﻭﻥ‬ (Open Hydraulic Circuit) ‫ﺍﻟﻌﻤل‬ ‫ﻭﻓﺘﺭﺓ‬ ‫ﺍﻟﺤﺭﺍﺭﺓ‬ ‫ﺩﺭﺠﺔ‬ ‫ﻋﻠﻰ‬ ‫ﻜﺒﻴﺭ‬ ‫ﺒﺸﻜل‬ ‫ﻴﻌﺘﻤﺩ‬ ‫ﺍﻟﻤﻨﻅﻭﻤﺔ‬ ‫ﺸﻐل‬ ‫ﻭﺇﻥ‬. Introduction Hydraulic systems utilize the process of energy conversion and transmission. The process of energy conversion and transmission involve losses in which mechanical and hydraulic energy is converted into heat. The operating temperature is one of the factors governing the efficiency of a hydraulic system. Where the temperature of the hydraulic fluid depends on:-The power losses-The place of installation-The surface area of heat-radiating components (such as tank)