scholarly journals Enhanced Teacher Learning Based Optimization on Organic Rankine Cycle in Shell and Tube Heat Exchanger

2021 ◽  
Vol 14 (6) ◽  
pp. 105-114
Keyword(s):  
Heat Exchanger ◽  
Teacher Learning ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Tube Heat Exchanger ◽  
Shell And Tube

scholarly journals Performance assessment of shell and tube heat exchanger based subcritical and supercritical organic Rankine cycles

2018 ◽  
Vol 22 (Suppl. 3) ◽  
pp. 855-866
Author(s):  
Anil Erdogan ◽  
Ozgur Colpan
Keyword(s):  
Heat Exchanger ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
System Level ◽  
Two Phase ◽  
Detailed Model ◽  
Tube Heat Exchanger ◽  
Organic Rankine Cycles ◽  
Level Model ◽  
Shell And Tube

In this study, thermal models for subcritical and supercritical geothermal powered organic Rankine cycles are developed to compare the performance of these cycle configurations. Both of these models consist of a detailed model for the shell and tube heat exchanger integrating the geothermal and organic Rankine cycles sides and basic thermodynamic models for the rest of the components of the cycle. In the modeling of the heat exchanger, this component was divided into sever?al zones and the outlet conditions of each zone were found applying logarithmic mean temperature difference method. Different Nusselt correlations according to the relevant phase (single, two-phase, and supercritical) were also included in this model. Using the system-level model, the effect of the source temperature on the performances of the heat exchanger and the organic Rankine cycle was assessed. These performance parameters are heat transfer surface area and pressure drop of tube side fluid for the heat exchanger, and electrical and exergetic efficiencies of the integrated organic Rankine cycles system. It was found that 44.12% more net power is generated when the supercritical organic Rankine cycle is used compared to subcritical organic Rankine cycle.

SIMULATION OF ORGANIC RANKINE CYCLE THROUGH FLUEGAS TO LARGE SCALE ELECTRICITY GENERATION PURPOSE

2015 ◽  
Vol 77 (27) ◽  
Author(s):  
Omid Rowshanaie ◽  
Saari Mustapha ◽  
Kamarul Arifin Ahmad ◽  
Hooman Rowshanaie
Keyword(s):  
Heat Exchanger ◽  
Large Scale ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Steady State Condition ◽  
Working Fluids ◽  
Tube Heat Exchanger ◽  
Heat Transfer Capacity ◽  
Mass Flow Rates ◽  
Shell And Tube

A simulation model of Organic Rankine Cycle (ORC) was developed with HYSYS software driven by R245fa, with NOVEC7000 and R141b as working fluids and Fluegas of boilers as a heat source of shell and tube Heat Exchanger to generate large scale electricity. The initial working condition was in subcooled liquid and steady state condition. R141b was found to generate the highest electricity power increment in specific mass flow rates and inlet pressures of Expander because of approaching its critical temperature to inlet Fluegas temperature. Howeever, in terms of economic considerations and cost of shell and tube Heat Exchanger that related to total heat transfer capacity, NOVEC7000 is the optimum selection. Furthermore, R245fa has the highest total effiiciency of ORC compared with other working fluids in this study.

scholarly journals Modelling of Polymeric Shell and Tube Heat Exchangers for Low-Medium Temperature Geothermal Applications

Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2737
Author(s):  
Francesca Ceglia ◽  
Adriano Macaluso ◽  
Elisa Marrasso ◽  
Maurizio Sasso ◽  
Laura Vanoli
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Power Plants ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Working Fluid ◽  
Heat Transfer Area ◽  
Geothermal Fluid ◽  
Shell And Tube

Improvements in using geothermal sources can be attained through the installation of power plants taking advantage of low and medium enthalpy available in poorly exploited geothermal sites. Geothermal fluids at medium and low temperature could be considered to feed binary cycle power plants using organic fluids for electricity “production” or in cogeneration configuration. The improvement in the use of geothermal aquifers at low-medium enthalpy in small deep sites favours the reduction of drilling well costs, and in addition, it allows the exploitation of local resources in the energy districts. The heat exchanger evaporator enables the thermal heat exchange between the working fluid (which is commonly an organic fluid for an Organic Rankine Cycle) and the geothermal fluid (supplied by the aquifer). Thus, it has to be realised taking into account the thermodynamic proprieties and chemical composition of the geothermal field. The geothermal fluid is typically very aggressive, and it leads to the corrosion of steel traditionally used in the heat exchangers. This paper analyses the possibility of using plastic material in the constructions of the evaporator installed in an Organic Rankine Cycle plant in order to overcome the problems of corrosion and the increase of heat exchanger thermal resistance due to the fouling effect. A comparison among heat exchangers made of commonly used materials, such as carbon, steel, and titanium, with alternative polymeric materials has been carried out. This analysis has been built in a mathematical approach using the correlation referred to in the literature about heat transfer in single-phase and two-phase fluids in a tube and/or in the shell side. The outcomes provide the heat transfer area for the shell and tube heat exchanger with a fixed thermal power size. The results have demonstrated that the plastic evaporator shows an increase of 47.0% of the heat transfer area but an economic installation cost saving of 48.0% over the titanium evaporator.

scholarly journals Heat Exchanger Sizing for Organic Rankine Cycle

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3615 ◽  
Author(s):  
James Bull ◽  
James M. Buick ◽  
Jovana Radulovic
Keyword(s):  
Heat Exchanger ◽  
Power Systems ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Working Fluid ◽  
Two Phase ◽  
Operational Conditions ◽  
Shell And Tube

Approximately 45% of power generated by conventional power systems is wasted due to power conversion process limitations. Waste heat recovery can be achieved in an Organic Rankine Cycle (ORC) by converting low temperature waste heat into useful energy, at relatively low-pressure operating conditions. The ORC system considered in this study utilises R-1234yf as the working fluid; the work output and thermal efficiency were evaluated for several operational pressures. Plate and shell and tube heat exchangers were analysed for the three sections: preheater, evaporator and superheater for the hot side; and precooler and condenser for the cold side. Each heat exchanger section was sized using the appropriate correlation equations for single-phase and two-phase fluid models. The overall heat exchanger size was evaluated for optimal operational conditions. It was found that the plate heat exchanger out-performed the shell and tube in regard to the overall heat transfer coefficient and area.

scholarly journals PERANCANGAN HRSG (HEAT RECOVERY STEAM GENERATOR) SEBAGAI PEMANAS REFRIGRANT R-134a PADA SIKLUS ORGANIC RANKINE CYCLE

2020 ◽  
Vol 12 (1) ◽  
pp. 35
Author(s):  
D. L. Zariatin ◽  
I. G.E. Lesmana ◽  
R. C. Hartantrie ◽  
Aditya Nugroho
Keyword(s):  
Heat Exchanger ◽  
Steam Generator ◽  
Flow Rate ◽  
Heat Recovery ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Heat Recovery Steam Generator ◽  
Shell And Tube ◽  
R 134A ◽  
Thermal Oil

Udara buang proses pirolisis masih menyimpan energi panas yang cukup tinggi dengan temperatur mencapai 800°C sehingga dapat dimanfaatkan sebagai media untuk merubah fase Refrigerant R-134a dari fase cair menjadi gas. Refrigerant R-134a yang sudah berubah menjadi gas digunakan untuk memutar turbin sebagai penggerak generator sehingga dapat menghasilkan aliran listrik dalam siklus Organic Rankine Cycle  (ORC). Refrigrant R-134a tidak menyerap panas dari proses pirolisis secara langsung. Panas dari pirolisis diserap melalui siklus thermal oil kemudian digunakan untuk mengubah fasa R-134a pada Heat Recovery Steam Generator (HRSG). Desain HRSG pada penelitian ini adalah tipe sistem Heat Exchanger shell  and tube. Dimana thermal oil yang memiliki suhu panas mengalir dalam shell dan refrigerant R-134a yang memiliki suhu dingin mengalir dalam Tube. Pertukaran panas terjadi ketika Refrigerant R-134a masuk ke dalam tube dan thermal oil masuk ke dalam shell. Dalam perancangan HRSG ini digunakan tiga variasi tekanan yaitu 8 bars, 10 bar, dan 12 bar. Data suhu, tekanan, diameter tube, dan mass flow rate di-input pada software HTRI Xchanger suite kemudian diproses oleh software tersebut sehingga menghasilkan output berupa laju perpindahan panas. Nilai laju perpindahan panas berturut turut sebesar turut 2,084 kJ/s, 2,622 kJ/s, dan 3,02kJ/s. Sehingga dapat disimpulkan hasil yang paling optimal berada pada tekanan 12 bar dengan nilai laju perpindahan panas sebesar 3,02 kJ/s Kata kunci: shell and tube HRSG, HTRI Xchanger suite, Organic Rankine Cycle

Waste Heat Recovery From the Exhaust of a Diesel Generator Using Shell and Tube Heat Exchanger

2013 ◽  
Author(s):  
Shekh N. Hossain ◽  
Saiful Bari
Keyword(s):  
Computer Simulation ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Heat Recovery ◽  
Rankine Cycle ◽  
Working Fluid ◽  
Diesel Generator ◽  
Tube Heat Exchanger ◽  
Hfc 134A ◽  
Shell And Tube

The heat from exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Bottoming Rankine Cycle (RC) is one of the promising techniques to recover heat from the exhaust. One derivative of RC known as Organic Rankine Cycle (ORC) is also suitable for heat recovery for moderate and small size engines as the exhaust heat content and temperature of these engines are low. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. In this current research, a shell and tube heat exchanger is optimized by computer simulation for two working fluids, water and HFC-134a. Two shell and tube heat exchangers were purchased and installed into a 40 kW diesel generator. The performance of the heat exchangers using water as the working fluid was then conducted. With the available data, computer simulation was carried out using CFD software ANSYS CFX14.0 to improve the design of the heat exchanger for both fluids. Geometric variables including length, number of tubes, and baffle design are all tested separately. Using the optimized heat exchangers simulation was conducted to estimate the possible additional power generation considering 80% isentropic turbine efficiency. The proposed heat exchanger was able to produce 11% and 9.4 % additional power using water and HFC-134a as the working fluid at maximum working pressure of 15 and 40 bar respectively. This additional power results into 12% and 11% improvement in brake-specific fuel consumption (bsfc) by using water and HFC-134a respectively. This indicates that besides water, organic fluids can also be a suitable option to recover heat from the exhaust of diesel engine.

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