Studies on an Ammonia-Water Compression-Absorption Cooling System (CACS) Drived by Solar Energy

Author(s):  
Zezheng Qiu ◽  
Yulie Gong ◽  
Huashan Li ◽  
Weibin Ma
2020 ◽  
pp. 340-340
Author(s):  
Bayram Kiliç ◽  
Osman İpek

Together with the developing nano technology, nano-fluids and nano-particles are used as working fluid in energy applications. It is foreseen that nanoparticles have high heat conduction coefficient and it will increase system performance by using as a working fluid in energy systems. Many studies in the literature show that nano fluids increase the heat transfer rate by improving heat transfer. In this study, a performance analysis of an absorption cooling system using solar energy was performed as numerically. LiBr-Al2O3/water nano-fluid has been used in the cooling system as working fluid. The thermodynamic values and calculations used in the analyses were performed with Engineering Equation Solver program. Heat load necessary for the generator is provided with a flat plate solar collector. For different operation condition, the variation of COP values was determined depend on Al2O3/water nanoparticle concentration ratio. When the Al2O3/water nanoparticle concentrations are changed as 0%, 0.5% and 0.1%, it was determined that the COP values increased. Nanoparticles added to the refrigerant at certain concentration values affects the COP values positively of cooling systems. Maximum COP value is 0.86 for 85?C generator temperature and 0.1% Al2O3/water nanoparticle concentration. The lowest COP value was obtained for the 75 oC generator temperature. When the Al2O3/water nanoparticle concentration was increased together with the generator temperature, COP values also increased. When the nanoparticle concentration of the working fluid increases, the viscosity of the nanofluid can be increases. Due to, increased viscosity increases the pressure drop in the flow channel and the pump power required for the flow. Thus, 'minimum viscosity with maximum thermal conductivity' optimisation in applications is very important.


2020 ◽  
Vol 3 (1) ◽  
pp. 609-618
Author(s):  
Ozan Sen ◽  
Ceyhun Yilmaz

In this study, geothermal and solar energy assisted cogeneration energy system has been modeled to supply residences' electricity and cooling requirements. The geothermal water from the geothermal resource and the heat transfer fluid heated in the parabolic collector is used as the heat source in the absorption cooling system. Electricity is generated in the binary power plant with geothermal water and heat transfer fluid from the absorption cooling system. The generated electricity is supplied to the grid. Thermoeconomic analysis of the system is performed by using the Engineering Equation Solver (EES) program by using geothermal and solar energy values of Afyonkarahisar. The geothermal resource's temperature and mass flow in the system is 130 ºC and 85 kg/s, respectively. The parabolic trough collector operates in the range of monthly average solar radiation values (500-600 W/m2) calculated for the summer season, where cooling is planned. The LiBr-H2O solution is chosen as the refrigerant of the absorption cooling system. The system's parametric study is performed by considering the different geothermal resource temperatures and solar radiation values. According to these results, the unit electricity and unit cooling costs produced in the system will be investigated. The optimum working conditions are investigated in producing and using the energy form (electricity-cooling) requirements.


Sign in / Sign up

Export Citation Format

Share Document