Study On The Law And Prediction Model Of Temperature And Pressure In Horizontal Gas Well

Horizontal well technology is widely used in the exploitation of oil and gas reservoirs because it can improve the recovery factor.Gas-liquid two-phase flow often occurs in horizontal wells.The in-depth study of the temperature and pressure distribution in the wellbore is of great significance for analyzing oil and gas reservoir productivity and optimizing production processes.In this paper,a perforated horizontal wellbore experimental device is designed to simulate the perforated horizontal wellbore from the aspects of perforation cluster opening method,intercluster interference,perforation inflow flow rate,and liquid holding rate.Distribution of temperature and pressure in the medium,and corresponding prediction models are proposed.The average relative error of the temperature prediction model is within 4% and the average relative error of the pressure drop prediction model is within 20%.The pressure distribution in the wellbore is verified with numerical simulation for further analysis.The study found that the perforation opening method has a great impact on the distribution of temperature and pressure in the wellbore.As the number of perforations increases,the flow-temperature curve becomes smoother,and the pressure in the wellbore is higher,but the overall change trend the same;With the same number of perforations,the more uniform the perforation distribution,the smoother the temperature change in the wellbore.The effect of inter-cluster interference on pressure and temperature is similar.The effect of inter-cluster interference on pressure is closely related to the distance and relative position between clusters.The larger the inter-cluster distance,the smaller the mutual interference,and the impact of upstream clusters is much greater than Impact of downstream clusters.For two-phase flow in the perforation,the amount of liquid production has a significant effect on the temperature distribution in the wellbore.The larger the liquid volume,the weaker the temperature drop effect caused by the energy loss caused by the gas throttling of the same gas volume;the liquid volume increases The more the pressure increases,the greater the pressure increase in the wellbore.When the gas volume exceeds 200m~3/h,the effect of the liquid volume on the wellbore pressure becomes more obvious.The presence of fluid in the wellbore also has a great impact on the distribution of temperature and pressure.The more fluid accumulates,the smoother the temperature distribution becomes.When the fluid holding rate in thewellbore is below 50% and the perforation air intake is greater than 200m~3 / h When the gas volume increases,the pressure increases.When the liquid holding rate is greater than 50%,the smaller the gas volume,the lower the temperature in the cylinder,and the pressure will fluctuate only in the vicinity of the first perforation cluster.This study provides a theoretical basis for gas well mining projects.The laboratory experiment has enriched the research content of horizontal wellbore gas production process,and it also has certain guiding significance for the interpretation of gas production technology by temperature and pressure profile.