Experimental characterization of globe and gate valves in vertical gas–liquid flows

Abstract

Valves are mechanical devices commonly used in pipelines and pipe networks for industrial applications, including petroleum, power and process industries. In two-phase flows more complex flowing conditions occur and special attention must be paid to predict pressure losses. To date, studies on two-phase flows through valves have been mainly devoted to safety relief valve (SRV). This paper presents the results of an experimental characterization study of a globe and a gate valves 2″ DN. The aim of the study is to investigate the flow through this type of valve, to understand the phenomena that occur inside and to improve models to calculate pressure drops in two-phase flow conditions.The valve has been preliminary characterized in single phase flow obtaining quite good results. The flow coefficient of the valve has been determined in order to proceed in two phase tests. Comparison between two phase flow measured data and predictive models has been considered. The Chisholm model seems to give the best agreement with the data in the observed interval for the globe valve. The best model for the gate valve seems to be the Lockart–Martinelli modified model. Predicting pressure drops in both cases, the average error is close to zero and less than ±10%.