摘要 |
<p>An outlet valve for a high pressure pump which is designed to alleviate "sticking" of the moveable valve element. An annular recess is formed at a transitional flow area where high pressure fluid flows forwardly and then radially outwardly between contact surfaces of the valve element and a valve seat member. It is believed this alleviates a problem of separated flow at the transition area which would effectively decrease the flow area and cause a localized pressure reduction which would delay proper opening of the valve element. Also, other configurations are shown for tripping the boundary layer to avoid separation, and other configurations to alleviate the same.</p> |