Hamid Reza Nasriani - South Zagros Oil and Gas Production Company, Iranian Central Oil Fields Co. (ICOFC), National Iranian Oil
Azim Kalantari Asl - South Zagros Oil and Gas Production Company, Iranian Central Oil Fields Co. (ICOFC), National Iranian Oil
M. Shabaninejad - South Zagros Oil and Gas Production Company, Iranian Central Oil Fields Co. (ICOFC), National Iranian Oil
M. Shabaninejad - South Zagros Oil and Gas Production Company Iranian Central Oil Fields Co. (ICOFC) National Iranian Oil

Flow through a surface choke can be described as either critical or sub-critical. Most of the correlations available to petroleum engineers are for critical flow but in lots of high rate gas/condensate wells subcritical flow occurs in large choke sizes. Field data of fifteen high rate wells producing from ten gas condensate reservoir located in Iran were used to develop a general Gilbert type formula obtained by non-linear regression of data points for gas condensate wells. The present study develop a general Gilbert type formula for gas condensate wells, flowing through differentlarge choke sizes between 40/64 in. and 192/64 in. under subcritical flow conditions in order to develop empirical correlations to be applied to predict gas flow rates under wide range of flow conditions usually encountered during the flow of gas condensates through wellhead chokes in wells. A comparison between the measured data and observed data is done with five different errors parameters. The results of this study could be considered in the design and implementation of deliverability tests, pressure transient tests, well control, and long-term well production of high rate gas condensates wells.

Choke performance, sub-critical flow, gas condensate, non-linear regression, errors analysis