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Jun 11, 2015 - simulating steam-water flow in steam injection wells and geothermal wells. In particular, for the heat exchange between the fluids in wellbore. Coefficient can be used to convert the single-tubing correlations to the. Fluid flow and heat transfer in wellbores Download fluid flow and heat transfer in wellbores or read online books in PDF, EPUB, Tuebl, and Mobi Format. Click Download or Read Online button to get fluid flow and heat transfer in wellbores book now. This site is like a library, Use search box in the widget to get ebook that you want.

Heat

• • 2k Downloads • Abstract The conventional geothermal power plants use the reinjection wells mostly to avoid the depletion of the geothermal reservoir gathering in the underground of the produced brine. Nevertheless, reinjection operations entail high economic costs and some risks.

An alternative is the extraction of the heat without geothermal fluids production, the wellbore heat exchanger. The goal of the present paper is the analysis of the power production of the wellbore heat exchanger (WBHX) in time and the comparison between two different conversion systems of the thermal energy into electrical: the organic ranking cycle (ORC) plant and the Stirling motor. The selected case study is the oil field of Villafortuna Trecate, a medium enthalpy geothermal resource. The simulation results show a substantial decrease of the wellhead temperature in the first 6 months. After 1 year, the thermal power extracted with the WBHX is greater than 1.3 MW. The design parameters are 20 m 3/h for the flow rate, outlet temperature 100.38 °C and the inlet temperature is 40 °C.

The R-C318 has been selected as working fluid in the ORC plant: the net electrical power is 121 kW. The air is the working fluid in the Stirling motor: the evaluated net electrical power is 152 kW. The Stirling engine has an efficiency greater than 41% compared to a system ORC. Fig. 1 WBHX: cross section and schematic Some researchers have studied the operative parameters that influence the feasibility and efficiency of the power plants based on WBHX. Among them are the geothermal gradient, the bottomhole temperature, the depth of the well, the properties and the flow rate of the selected working fluid, the thermal insulation between the two pipes that compose the heat exchanger (Kujawa et al.; Davis and Michaelides; Bu et al.; Cheng et al., ).

Several studies have proposed the use of the borehole exchangers to convert the abandoned oil wells into geothermal ones (Kujawa et al.; Zhang et al.; Wang et al.; Davis and Michaelides; Bu et al.; Cheng et al.; Templeton et al.; Cheng et al. Considering the drilling costs almost 25% of the total costs of the power plant (Hance ), and the high costs of closure of the oil fields, the use of the WBHX could be an economic advantage both for oil companies and for geothermal companies. The main weakness of the deep borehole heat exchanger is a low efficiency in heat recovery compared to a conventional geothermal technology. This is due to the lower mass flow rate and to the indirect exchange of heat, which causes a lower wellhead temperature. However, the use of a WBHX could be a solution to extract heat from unconventional geothermal systems, such as magmatic or hypersaline reservoirs, where there are fluids with particular physical and chemical characteristics.

We have been the leading provider of polar adventure travel for over 25 years and offer travelers unparalleled access to the most remote places on earth aboard a diverse fleet of specially-equipped small expedition vessels, icebreakers, and unique land-based adventures. The spirit of exploration runs deep in our polar pedigree and we are passionate about creating transformational experiences for fellow adventurers visiting these regions. Quark Expeditions is uncompromisingly polar, specializing in expeditions to the Antarctic and the Arctic. Kniga kapitan blad vozvraschaetsya 2.

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Jun 11, 2015 - simulating steam-water flow in steam injection wells and geothermal wells. In particular, for the heat exchange between the fluids in wellbore. Coefficient can be used to convert the single-tubing correlations to the. Fluid flow and heat transfer in wellbores Download fluid flow and heat transfer in wellbores or read online books in PDF, EPUB, Tuebl, and Mobi Format. Click Download or Read Online button to get fluid flow and heat transfer in wellbores book now. This site is like a library, Use search box in the widget to get ebook that you want.

Heat

• • 2k Downloads • Abstract The conventional geothermal power plants use the reinjection wells mostly to avoid the depletion of the geothermal reservoir gathering in the underground of the produced brine. Nevertheless, reinjection operations entail high economic costs and some risks.

An alternative is the extraction of the heat without geothermal fluids production, the wellbore heat exchanger. The goal of the present paper is the analysis of the power production of the wellbore heat exchanger (WBHX) in time and the comparison between two different conversion systems of the thermal energy into electrical: the organic ranking cycle (ORC) plant and the Stirling motor. The selected case study is the oil field of Villafortuna Trecate, a medium enthalpy geothermal resource. The simulation results show a substantial decrease of the wellhead temperature in the first 6 months. After 1 year, the thermal power extracted with the WBHX is greater than 1.3 MW. The design parameters are 20 m 3/h for the flow rate, outlet temperature 100.38 °C and the inlet temperature is 40 °C.

The R-C318 has been selected as working fluid in the ORC plant: the net electrical power is 121 kW. The air is the working fluid in the Stirling motor: the evaluated net electrical power is 152 kW. The Stirling engine has an efficiency greater than 41% compared to a system ORC. Fig. 1 WBHX: cross section and schematic Some researchers have studied the operative parameters that influence the feasibility and efficiency of the power plants based on WBHX. Among them are the geothermal gradient, the bottomhole temperature, the depth of the well, the properties and the flow rate of the selected working fluid, the thermal insulation between the two pipes that compose the heat exchanger (Kujawa et al.; Davis and Michaelides; Bu et al.; Cheng et al., ).

Several studies have proposed the use of the borehole exchangers to convert the abandoned oil wells into geothermal ones (Kujawa et al.; Zhang et al.; Wang et al.; Davis and Michaelides; Bu et al.; Cheng et al.; Templeton et al.; Cheng et al. Considering the drilling costs almost 25% of the total costs of the power plant (Hance ), and the high costs of closure of the oil fields, the use of the WBHX could be an economic advantage both for oil companies and for geothermal companies. The main weakness of the deep borehole heat exchanger is a low efficiency in heat recovery compared to a conventional geothermal technology. This is due to the lower mass flow rate and to the indirect exchange of heat, which causes a lower wellhead temperature. However, the use of a WBHX could be a solution to extract heat from unconventional geothermal systems, such as magmatic or hypersaline reservoirs, where there are fluids with particular physical and chemical characteristics.

We have been the leading provider of polar adventure travel for over 25 years and offer travelers unparalleled access to the most remote places on earth aboard a diverse fleet of specially-equipped small expedition vessels, icebreakers, and unique land-based adventures. The spirit of exploration runs deep in our polar pedigree and we are passionate about creating transformational experiences for fellow adventurers visiting these regions. Quark Expeditions is uncompromisingly polar, specializing in expeditions to the Antarctic and the Arctic. Kniga kapitan blad vozvraschaetsya 2.