The relationship between production rates of large diameter geothermal production wells, and slimholes, is studied. The analysis is based on wells completed in liquid-dominated geothermal fields, where flashing occurs either in the wellbore or at the surface. Effects of drawdown in the reservoir, and pressure drop in the wellbore, are included; heat losses from the wellbore to the formation are not presently included in our analysis. The study concentrates on the influence of well diameter on production rate. For situations where the pressure drop is dominated by the reservoir, it is found that the mass flowrate varies with diameter according to W - Da, where the exponent a is a function of reservoir outer radius, well diameter and skin factor. Similarly, when pressure drop in the wellbore is dominant, the scaling exponent was found to be a function of well diameter and pipe roughness factor. Although these scaling laws were derived for single-phase flow, numerical simulations showed them to be reasonably accurate even for cases where flashing occurs in the wellbore.

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