Mahnaz Hekmatzadeh - IOR Research Institute, National Iranian Oil Company, Tehran, Iran
Habib Valiollahi - IOR Research Institute, National Iranian Oil Company, Tehran, Iran
Shahab Gerami - IOR Research Institute, National Iranian Oil Company, Tehran, Iran

In order to accurately predict the performance of a gas condensate well using numerical simulation, local grid refinement is inevitable, otherwise the effects of condensate blockage and high velocity of gas could not be properly captured. But, the complexities of such calculation make the numerical simulation time-consuming. On the other hand, to conduct uncertainty analysis on the reservoir and well parameters, this calculation package must be repeated thousands of times. Therefore, a faster method for calculation of gas condensate well flow rate is of a precious value. In this paper a fast semi-analytical method is introduced for calculation of flow rate in gas condensate wells and then based on Monte-Carlo procedure, an uncertainty analysis study is conducted for verticalwell. Uncertainty analysis is absolutely necessary at the beginning of a reservoir's life and it can help the reservoir managers to make the most possible realistic decision for development plan, infrastructure, and the sale contracts for produced gas and condensate. The finding of the study is realizing the uncertain parameters that have the biggest impacts on the accuracy of production prediction, and if there is any budget for reducing uncertainties, this budget should be invested on those parameters, rather than unimportant parameters. For the particular studied case in this work, porosity is the most influential uncertain parameter

Gas Condensate, Productivity, Uncertainty Analysis, High Velocity Effects