Study On Throttling Notche Thermal Characteristics Of Slide Valve

Spool valves as the underlying hydraulic components are widely used in the hydraulic system, its technical level and the quality of performance, directly determines the performance of the hydraulic system and the quality. With the continuous development of hydraulic technology, the performance of the hydraulic valve put a higher demand; especially because of the problem caused by changes in temperature affecting the hydraulic valve operation has become a big problem. When the spool valves are used in the normal operating temperature range, they can maintain compliance with the design parameters of clearance and are not easy to wear and tear. But when the hydraulic oil temperature rises, spool valve will overheat and expand, and the clearance between the spool and the valve sleeve change. Because the clearance changes, the original size fitting is destroyed and fluid viscosity changes. If the gap becomes larger, it can lead to oil leakage increasing. And if the gap becomes smaller, it may cause spool valve clamping or stuck valve, so that the system does not work. Therefore studying optimal design of hydraulic valves and thermal properties become a very important practical significance.This article is mainly devoted to study the problems which the V-shaped spool valve in the course of the spool due to thermal throttling effect caused clamping, thermal stuck and the leakage. The numerical simulation results show that:the spool valve notch is the main area of throttling temperature, is the highest region of the valve surface temperature, and is the largest thermal deformation zone. The main contents are as follows:1. According to the basic laws of the hydromechanics, heat transfer theory and the expansion mechanism theory, proposes the theoretical mathematical model, and mainly consider the viscosity-temperature characteristics, turbulent and the selection of thermal transfer conditions.2. Study the slide valve cavity flow field:establish and mesh fluid and solid3-D model of the computational domain, import the model into FLUENT software and simulate, obtain the distribution of slide valve chamber fluid’s pressure, speed and temperature in different valve opening and different working pressure, analyze the results.3. Research slide valve body temperature characteristics:establish a V-shaped slide valve of3-D analysis model of steady-state thermal, and put the results obtained in the calculation of fluid into the steady-state thermal analysis model, and the spool start to simulate, and the values are discussed on the study. 4. Study the spool body’s heat distortion: put the thermal analysis and calculation results into structural analysis module, and simulate thermal deformation analysis, and study the impact of the spool surface temperature and deformation after changing spool notch physical parameters and structural parameters, finally identify the main factors which affect the clamping slide valve thermal and thermal phenomena stuck to improve hydraulic value clamping and stuck.