PDF Publication Title:
Text from PDF Page: 004
designing a supersonic, converging-diverging nozzle, hence ensuring high levels of efficiency even at off-design operation due the variability of the heat source. The turbine efficiency at the design point was estimated using the performance charts developed by Perdichizzi and Lozza (1987). The working fluid Novec 649 was selected after screening different working fluid candidates from REFPROP (Lemmon et al., 2002) based on the following criteria: (i) zero ozone depletion potential; (ii) low global warming potential (< 150); (iii) no toxicity; (iv) no flammability; (v) thermal stability without decomposition up to 300 ◦C (3M, 2009); (vi) high cycle net power output and turbine efficiency (> 80 %); (vii) acceptable values of turbine rotational speed and rotor diameter. The choice of the working fluid Novec 649 for ORC systems has also been made in other studies (Cogswell et al., 2011; Reinker et al., 2015; Bonk et al., 2017). Table 2 lists the design conditions obtained for the two turbine case studies and their performance using the mean-line model. 2.4 Multi-objective turbine optimization A multi-objective optimization was performed on the two reference turbines to improve simultaneously the values of efficiency and manufacturability indicator. The optimization problem was formulated as follows: [U r6sr6h ] [min(−ηts),min(Iman)] = f(X) and X = C ,N, r , r ,Ris,Zr,Zs 0 4 6s (4) where U /C0 is the velocity ratio, N the rotational speed, r6h and r6s the rotor exit hub and shroud radii, r4 the tip radius, Ris the isentropic degree of reaction, Zr and Zs the number of rotor and nozzle blades, respectively. The optimization was performed using turbine geometric and fluid-dynamic constraints to achieve a reasonable design according to the indications by Rohlik (1968), Aungier (2006), Moustapha et al. (2003) and Perdichizzi and Lozza (1987). 3. RESULTS AND DISCUSSION 3.1 Optimal designs Figure 1 shows the Pareto fronts of the optimization for the air and the Novec 649 turbines. Five points in the Pareto front, from (i) to (v), were selected and analyzed. The Pareto front of the air turbine, illustrated in Fig. 1(a), indicates that the total-to-static efficiency varies from approximately 86.5 % to 79.5 %, with a relative and absolute change of about 8.1 % and 7 %-points, respectively. Better manufacturability can be achieved from the point (v) to (i), at the expenses of a lower efficiency. In this case, the manufacturability indicator changes from 2.35 to 1.42, suggesting an improvement of about 39.6 % in the turbine manufacturability. The Pareto front obtained in Fig. 1(a) is constrained at low values of efficiency (point (i)) due to the onset of choking conditions in the rotor blades while it is constrained at high value due to the maximum limit of −60° in the rotor exit shroud blade angle, in order to avoid the occurrence of excessive flow separation. Fig. 1(b) suggests that a larger variation in efficiency and manufacturability is obtained for the ORC turbine. The efficiency is in the range 85.7 % to 71.4 %, with a relative and absolute change of up to 16.7 % and 14.3 %-points, respectively. The manufacturability indicator is in the range 2.76 to 0.95, suggesting an improvement in manufacturability up to 65 % from point (v) to point (i). The Pareto front of the Novec 649 turbine is limited at point (v) due to the rotor exit blade constraint, close to −60°, and at point (i) due to onset of choking in the rotor as well as the minimum values of blade twist, which is close to zero. When the manufacturability indicator decreases in the Pareto front, the total-to-static efficiency of the optimal solutions reduces. Figure 2(a) depicts the breakdown of losses of the five points in the Pareto front for both the air and ORC turbines. The results indicate that the change in efficiency for the air turbine is dominated by the nozzle losses, which increase when the rotor has a low manufacturability indicator (easy to manufacture) to maintain the specified total-to-static pressure ratio through the stage. This aspect is also present in the breakdown of losses of the ORC turbine, although the main responsible for 5th International Seminar on ORC Power Systems, September 9-11, 2019, Athens, Greece Paper ID: 57, Page 4PDF Image | RADIAL-INFLOW TURBINES FOR ORGANIC RANKINE CYCLE POWER
PDF Search Title:
RADIAL-INFLOW TURBINES FOR ORGANIC RANKINE CYCLE POWEROriginal File Name Searched:
design-radial-inflow-turbine-for-orc.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)