Geothermal well behaviour prediction after air compress stimulation using one-dimensional transient numerical modelling

Padjadjaran Earth Dialogues: International Symposium on Geophysical Issues

Yusman, W.^1,4 ; Viridi, S.^2,4 ; Rachmat, S.^3,4

Geothermal Engineering, Faculty of Mining and Petroleum Engineering, Indonesia^1

Nuclear Physics and Biophysics, Faculty of Mathematics and Natural Science, Indonesia^2

Petroleum Engineering, Faculty of Mining and Petroleum Engineering, Indonesia^3

Institute Teknologi Bandung, Ganesha 10 st., Bandung

40132, Indonesia^4

关键词: Behavior prediction;    Field conditions;    Field observations;    Geothermal development;    Geothermal fluids;    Geothermal reservoir;    Prediction methods;    Single phase fluids;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/29/1/012008/pdf
DOI  :  10.1088/1755-1315/29/1/012008

来源: IOP

【 摘 要 】

The non-discharges geothermal wells have been a main problem in geothermal development stages and well discharge stimulation is required to initiate a flow. Air compress stimulation is one of the methods to trigger a fluid flow from the geothermal reservoir. The result of this process can be predicted by using by the Af / Ac method, but sometimes this method shows uncertainty result in several geothermal wells and also this prediction method does not take into account the flowing time of geothermal fluid to discharge after opening the well head. This paper presents a simulation of non-discharges well under air compress stimulation to predict well behavior and time process required. The component of this model consists of geothermal well data during heating-up process such as pressure, temperature and mass flow in the water column and main feed zone level. The one-dimensional transient numerical model is run based on the Single Fluid Volume Element (SFVE) method. According to the simulation result, the geothermal well behavior prediction after air compress stimulation will be valid under two specific circumstances, such as single phase fluid density between 1 - 28 kg/m3and above 28.5 kg/m3. The first condition shows that successful well discharge and the last condition represent failed well discharge after air compress stimulation (only for two wells data). The comparison of pf values between simulation and field observation shows the different result according to the success discharge well. Time required for flow to occur as observed in well head by using the SFVE method is different with the actual field condition. This model needs to improve by updating more geothermal well data and modified fluid phase condition inside the wellbore.