The Discharging Well

  • Arnold Watson


Once discharge is achieved, the discharge flow rate and its temperature, pressure and specific enthalpy can be measured; several methods are available. The main parameters are presented as “discharge characteristics”, which are required for power station control but also contain information about the producing formations. The chemical constituents of the discharge are measured at the same time as the discharge characteristics and provide further clues as to conditions in the producing formations. Some wells discharge at a steady flow rate, with perhaps a long-term decline as the formation pressure declines, but some have a periodic flow or even a regular intermittent discharge like a geyser. It is sometimes useful to have a means of predicting the details of the flow during discharge, and numerical discharge prediction methods have been developed. All of these matters are discussed in this Chapter.


Mass Flow Rate Discharge Characteristic Lower Zone Specific Enthalpy Orifice Plate 
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  1. Brennand AW, Watson, A (1987) Use of the ESDU compilation of two-phase flow correlations for the prediction of well discharge characteristics. In: Proceedings of 9th NZ Geothermal Workshop, University of AucklandGoogle Scholar
  2. Chevron Corporation (1988) US Patent No 4788848Google Scholar
  3. Durand P, Juan Torres JL (1996) Solute transfer in agricultural catchments; the interest and limits of mixing models. J Hydrol 181:1–22CrossRefGoogle Scholar
  4. Ellis AJ, Mahon WAJ (1977) Chemistry and geothermal systems. Academic, New YorkGoogle Scholar
  5. Elmi D, Axelsson G (2009) Application of a transient wellbore simulator to wells HE-06 and HE-20 in the Hellisheidi geothermal system, SW-Iceland. In: Proceedings of 34th Workshop on Geothermal Reservoir Engineering, StanfordGoogle Scholar
  6. ESDU (1978) Guide to calculation procedures for solving typical problems related to pressure drop in two-phase systems, ESDU 780018Google Scholar
  7. ESDU (2008) Pressure gradient in upward adiabatic flows of gas–liquid mixtures in vertical pipes, ESDU 04006Google Scholar
  8. Fournier RO (1977) Chemical geothermometers and mixing models for geothermal systems. Geothermics 5:41–50CrossRefGoogle Scholar
  9. Glover RB, Lovelock BG, Ruaya JR (1981) A novel way of using gas and enthalpy data. In: Proceedings of 3rd NZ Geothermal Workshop, University of AucklandGoogle Scholar
  10. Grant, MA (1979) Interpretation of downhole measurements in geothermal wells, Report No. 88, Applied Maths Division, Department of Scientific and Industrial Research, NZGoogle Scholar
  11. Helbig S, Zarrouk SJ (2012) Measuring two-phase flow in geothermal pipelines using sharp-edged orifice plates. Geothermics 44:52–64CrossRefGoogle Scholar
  12. James R (1962) Steam-water critical flow through pipes. Proc Inst Mech Eng 176(26):741CrossRefGoogle Scholar
  13. James R (1965) Metering of steam-water two-phase flow by sharp edged orifices. Proc Inst Mech Eng 180:549–566CrossRefGoogle Scholar
  14. James R (1966) Measurement of steam-water mixtures discharging at the speed of sound to the atmosphere. NZ Eng 21(10):27Google Scholar
  15. Karaalioglu H, Watson A (1999) A comparison of two wellbore simulators using field measurements. In: Proceedings of 21st NZ Geothermal Workshop, University of AucklandGoogle Scholar
  16. Kestin J (ed) (1980) Sourcebook on the production of electricity from geothermal energy, US DoE, Contract No EY-76-S-4051.A002Google Scholar
  17. Kieffer S (1977) Sound speed in liquid–gas mixtures: water-air and water-steam. J Geophys Res 82(10):2895CrossRefGoogle Scholar
  18. King TR, Freeston DH, Winmill RL (1995) A case study of wide diameter casing for geothermal systems. In: Proceedings of 17th NZ Geothermal Workshop, University of AucklandGoogle Scholar
  19. Leaver JD, Freeston DH (1987) Simplified prediction of output curves for steam wells. In: Proceedings of 9th NZ Geothermal Workshop, University of AucklandGoogle Scholar
  20. Lovelock B (2006) Flow testing in Indonesia using alcohol tracers. In: Proceedings of 31st Workshop on Geothermal Reservoir Engineering, Stanford UniversityGoogle Scholar
  21. Lovelock BG, Baltasar SJ (1983) Geochemical techniques applied to medium term discharge tests in Tongonan. In: Proceedings of 5th NZ Geothermal Workshop, University of AucklandGoogle Scholar
  22. Lovelock BG, Cope DM, Baltasar AJ (1982) A hydrogeochemical model of the Tongonan geothermal field, Philippines. In: Proceedings of Pacific Geothermal Conference incorporating the 4th NZ Geothermal Workshop, University of AucklandGoogle Scholar
  23. Lu X (2004) An investigation of transient two-phase flow in vertical pipes with particular reference to geysering PhD thesis, Department of Mechanical Engineering, University of Auckland, New ZealandGoogle Scholar
  24. Lu X, Watson A, Gorin AV, Deans J (2005) Measurements in a low temperature CO2 driven geysering well, viewed in relation to natural geysers. Geothermics 34:389–410CrossRefGoogle Scholar
  25. Lu X, Watson A, Gorin AV, Deans J (2006) Experimental investigation and numerical modeling of transient two-phase flow in a geysering well. Geothermics 35:409–427CrossRefGoogle Scholar
  26. Menzies AJ (1979) Transient pressure testing. In: Proceedings of NZ Geothermal Workshop, University of AucklandGoogle Scholar
  27. Menzies AJ, Gudmundsson JS, Horne RN (1982) Flashing flow in fractured geothermal reservoirs. In: Proceedings of 8th Workshop on Geothermal Reservoir Engineering, StanfordGoogle Scholar
  28. Murdock JW (1962) Two-phase flow measurement with orifices. J Basic Eng 84:419CrossRefGoogle Scholar
  29. New Zealand Ministry of Energy (1985) The Rotorua geothermal field; technical report of the Rotorua Geothermal Task ForceGoogle Scholar
  30. Pinder GF, Jones JF (1969) Determination of the groundwater component of peak discharge from the chemistry of total runoff water. Water Resour Res 5:438–445CrossRefGoogle Scholar
  31. Ryley DJ (1964) Two-phase critical flow in geothermal steam wells. Int J Mech Sci 6(4):273CrossRefGoogle Scholar
  32. Thain IA, Carey B (2009) 50 years of geothermal power generation at Wairakei. Geothermics 38:48CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Arnold Watson
    • 1
  1. 1.51 Ash GroveTe AwamutuNew Zealand

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