2939 KB29 KB199920252015Feng, JilingGuo, YongchangLian, ZishengLiao, YaoyaoYuan, Hongbingštevilka:6letnik:61str. 355-364, SI 67ISSN:0039-2480COBISSID:14051611URN:URN:NBN:SI:doc-D6ZM4MLCenZveza strojnih inženirjev in tehnikov Slovenije et al.Strojniški vestnikhidravlični sistemihidravlično podporjehisterezahysteresispotni ventili za velike pretokeradialne neravnotežne sileResearch and analysis of the hysteresis characteristics of a large flow directional valve|The 1000 L/min large flow hydraulic system for the hydraulic support used in a coal mine is currently a topic of great interest. The large flow directional valve is a key component for hydraulic systems, so the design of the 1000 L/min large flow directional valve is essential. The designed single-channel valve shows serious hysteresis characteristics in a 1000 L/min large flow condition, but it does not happen in a 16 L/ min small flow condition. Based on this phenomenon, the computational fluid dynamics (CFD) technology was used to simulate the flow in the valve. It was discovered that the single-channel caused unbalanced pressure in the annular region and on the surface of the valve spool, so the valve spool is subjected to great radial unbalanced force. Then a double-channel valve was designed to improve the pressure distribution. The simulated radial unbalanced force on the double-channel valve is 67.2% lower than that of the single-channel valve. The experimental results showed that the hysteresis characteristics also disappeared under the 1000 L/min large flow condition. Therefore, the conclusion can be drawn that the hysteresis characteristics of the single-channel valve is due to the radial unbalanced force caused by the unsymmetrical flow field. The results show that the maximum radial unbalanced force the valve spool can withstand is 170 N. Furthermore, symmetrical flow passages have to be taken into account in large flow conditions. This paper provides valuable references for the design of large flow valvesV zadnjih letih je bilo odkritih več debelih premogovnih žil, ki zahtevajo hidravlično podporje na večjih globinah. Večji cilindri hidravličnega podporja pa delajo z večjimi pretoki in zato obstaja nujna potreba po hidravličnem sistemu za podporja s pretokom 1000 l/min, od tod pa potreba po zasnovi velikih potnih ventilov za omenjeni pretok. Pri preizkusu enokanalnega ventila na preizkuševališču za velike pretoke do 1000 l/min se je pokazala velika histereza pri izklopu, medtem ko so bili rezultati na manjšem preizkuševališču (do 16 l/min) dobri. Članek preučuje ta pojav histereze. Problem histereze pri potnem ventilu za pretok 1000 l/min je bil raziskan s kombinacijo pristopa CDF in eksperimentalnega testaTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo