Thermodynamic optimization of downhole heat exchangers for geothermal power generation
Parmanto, Slamet, author.

Thermodynamic optimization of downhole heat exchangers for geothermal power generation

Parmanto, Slamet, author.

Yazar Ek Girişi
Parmanto, Slamet, author.

Fiziksel Tanımlama
xi, 82 leaves:+ 1 computer laser optical disc.

Geothermal reservoirs have various thermodynamic and physical properties. The heat extraction and power generation from the geothermal reservoirs depend on the reservoir properties. Downhole heat exchangers (DHEs) are designed to move the heat extraction process into the geothermal well. The working fluid is injected to the DHE which suspends in the geothermal well, heated by geothermal fluid and then returned to the surface through the inner pipe. DHEs have been used for heating purposes widely but there is no application for electricity generation. Because of the natural convection on the geothermal fluid side, convective heat transfer coefficient is low and simultaneously the heat extraction rate is low comparing with extracting geothermal fluid by downhole pumps. Therefore if the temperature is high but flowrate is low in a geothermal well, DHEs are good alternatives to harness the energy from that well. Considering the number of wells with abovementioned conditions in the World, there is a potential for electricity generation coupling geothermal power plants with DHEs. The main purpose of the Thesis is to develop a thermodynamic and economic evaluation model of DHEs for power generation and to examine the feasibility of the model. The thermodynamic model is developed by EES software and over 300 simulations have been conducted to identify the effects of the insulation, geothermal well conditions, geometry of DHE, mass flowrate and the type of working fluids to the performance of DHE system. The economic analyses are conducted to evaluate the thermodynamic results regarding the economic consideration such as Net Present Value (NPV), simple payback time and electricity production rate. The results show that the insulation on the inner pipe is desirable to prevent heat loss along DHEs. The best design of the DHE is a design with deeper the depth, larger the diameter of the inner pipe, and higher mass flowrate for a specific geothermal heat source. The best design for the case study resulted as a work output of 3152 kW with annual net revenue and payback time of $1.75 million and 2.24 years, respectively. Besides, the economic evaluation gives positive value for NPV which means investment in DHE for geothermal power generation is acceptable.

Konu Başlığı
Heat exchangers -- Thermodynamics.
Heat exchangers.
Geothermal power plants.

Yazar Ek Girişi
Gökçlen Akkurt, Gülden

Tüzel Kişi Ek Girişi
İzmir Institute of Technology. Mechanical Engineering.

Tek Biçim Eser Adı
Thesis (Master)--İzmir Institute of Technology:Mechanical Engineering.
İzmir Institute of Technology: Mechanical Engineering--Thesis (Master).

Elektronik Erişim
Access to Electronic Versiyon.

KütüphaneMateryal TürüDemirbaş NumarasıYer NumarasıDurumu/İade Tarihi
IYTETezT001512TJ263 .P25 2016Tez Koleksiyonu