CRITICAL FLOW NOZZLE FLOWMETER FOR MEASURING RESPECTIVE FLOWS OF BOTH GAS AND LIQUID PHASES IN MULTIPHASE FLOW AND MEASURING METHOD

摘要

A critical flow nozzle flowmeter for measuring respective flows of both gas and liquid phases in a multiphase flow, comprising a throttling nozzle, which is provided with an inlet, an outlet (7), and a throat (6), where a flow area for a fluid is smallest at the throat part (6); a gamma ray detector, which comprises a gamma ray transmitter (3) and a gamma ray receiver (5), arranged in a way that allows the gamma ray transmitted by the gamma ray transmitter (3) to run in the diametrical direction through the cross-section at the inlet of the throttling nozzle and to reach the gamma ray receiver (5); pressure sensors (2 and 4) respectively used for measuring the pressure at the inlet and the pressure at the outlet of the throttling nozzle; a temperature sensor (2) used for measuring the temperature at the inlet of the throttling nozzle. The throttling nozzle flowmeter is applicable for use at an oilfield wellhead. Also provided is a measuring method for using the critical flow nozzle flowmeter in measuring the respective flows of both gas and liquid phases in the multiphase flow.