PDF Publication Title:
Text from PDF Page: 047
4 Study on dry ORC working fluids The objective of this chapter is to perform a preliminary evaluation of suitable working fluid candidates for small-scale ORC systems adopting high-speed turbines. First, a ther- modynamic analysis was carried out to highlight and discuss the special features related to the use of working fluids from different fluid groups, as well as to study the dependence of the critical temperature and molecular weight of the fluid on the most important pro- cess parameters. All the selected working fluids have a dry expansion to prevent droplets occurring in the turbine. In addition, the use of dry working fluids enables the use of a recuperator in the cycle. Second, a preliminary radial turbine design was carried out for several working fluids to evaluate and compare the availability for designing small-scale turbines with different fluids, as well as to investigate the main turbine dimensions and rotational speeds as a function of turbine power output. The selected turbine power output range is from 10 kW to 200 kW. 4.1 Thermodynamic analysis A thermodynamic analysis of subcritical processes adopting evaporation pressure slightly lower than the critical pressure of the fluid were carried out with two different condensing temperatures of 50 oC and 100 oC. The results were obtained by using the evaporation pressure of pev/pcr=0.9 for each fluid, in order to study processes having the evaporation pressure close to the critical pressure of the fluid and thus representing cycle efficiencies relatively close to the maximum efficiency that can be obtained with a subcritical process. It should be noted that this kind of approach was evaluated being suitable in the prelim- inary evaluation and in the comparison of working fluids, but in a more detailed design of ORC systems, the evaporation pressure of each fluid is highly dependent on the heat source temperature level as well as on the process optimization method. A more detailed thermodynamic analysis taking into account the temperature profiles in the heat exchang- ers is presented later in Chapter 5 and Chapter 7 for the studied applications. The vapor was superheated by 10 oC with all the fluids because a flow through type of evaporator was considered, which requires a superheating in the process (Talonpoika, 1996). Recuperator effectiveness of 0.6 was used which, enables the use of a recuperator, where the flow arrangement can also differ from the pure countercurrent flow configu- ration; and a feed pump efficiency of 60 % was used in the simulations. The turbine isentropic efficiency of 75 % was used in the simulations, which was evaluated as a real- istic value for the turbine efficiency when considering small-scale ORC turbines (Verneau, 1987; van Buijtenen et al., 2003; Kang, 2012). The thermodynamic analysis is structured as follows. First, the relation between the molecular weight and the critical temperature and the critical pressure is studied. Sec- ond, the relation between the cycle efficiency and the critical temperature is studied and discussed. Third, the relation between the critical temperature and the condensing pres- sure, the expansion ratio, and the enthalpy drop over the turbine are studied and discussed. 47PDF Image | WORKING FLUID SELECTION AND DESIGN OF SMALL-SCALE WASTE HEAT RECOVERY SYSTEMS BASED ON ORGANIC RANKINE CYCLES
PDF Search Title:
WORKING FLUID SELECTION AND DESIGN OF SMALL-SCALE WASTE HEAT RECOVERY SYSTEMS BASED ON ORGANIC RANKINE CYCLESOriginal File Name Searched:
Antti_Uusitalo_A_4_pdf_28_11__saa_painaa.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)