logo

Thermal Properties of Supercritical Carbon Dioxide

PDF Publication Title:

Thermal Properties of Supercritical Carbon Dioxide ( thermal-properties-supercritical-carbon-dioxide )

Previous Page View | Next Page View | Return to Search List

Text from PDF Page: 003

THERMAL PROPERTIES OF SC The isochoric heat capacity, Cv, can be calculated from thermodynamic relations as: CO2 BY MC SIMULATIONS 407 h􏴢›kVl􏴣 i2 ›T P b2P CP2Cv1⁄42T 􏴢›kVl􏴣 1⁄4TkVlk ð9Þ ›P T Finally, the Joule–Thomson coefficient, mJT, and speed of sound, u, can be expressed as: 􏴜›T􏴝 1 􏴚 􏴜›kVl􏴝 􏴛 mJT1⁄4 ›P 1⁄4C T ›T 2kVl hPP 1⁄4 kVl 1⁄2TbP 2 1􏴟 CP ð10Þ u 1⁄42Cv􏴢›kVl􏴣 N 1⁄4Cv N k ð11Þ CP kVl2 MNA CP MNA kVl ›P T where M is the molecular weight. Expressions for other thermodynamic properties, such as the adiabatic expansivity or the Gru ̈neisen parameter can be obtained from combinations of the relations in this section. POTENTIAL MODEL The model of Mo ̈ ller and Fischer for a 2CLJQ fluid [2] was used to describe CO2. A molecule is composed of two identical Lennard–Jones sites a distance l apart plus a point quadrupole moment Q placed in the geometric center of the molecule. The full potential, u2CLJQ, is written as: u2CLJQðrij; vi; vj; l; Q2Þ 1⁄4 u2CLJðrij; vi; vj; lÞ þuQðrij;vi;vj;Q2Þ ð12Þ 2 where u2CLJðrij; vi; vj; lÞ 1⁄4 41 r a1⁄41 b1⁄41 and uQðrij;vi;vj;Q Þ1⁄444p10jrijj51⁄2125ðci þcjÞ "# X2 X2 􏴜 s 􏴝12 2 􏴜 s 􏴝6 r 23Q2 22 215c2ic2j þ2ðc25cicjÞ2􏴟 ð14Þ ab ab ð13Þ FIGURE 1 consists of two LJ centers of diameter s separated by a distance l. Dispersion – repulsion interactions between the sites are calculated for all distances rab. (b) Point quadrupoles are located at the center of each 2CLJ molecule. Quadrupole – quadrupole interactions between two molecules depend on the orientation of the molecules (u1, u2, f) and the distance rij between the two molecules. Eq. (14), where rij is the center-to-center distance between two molecules, i and j (see Fig. 1b). The vectors vi and vj represent the orientation of molecules i and j; ui and uj are the angles between the axis of the molecule and the center-to-center connection line, and fij is the difference in azimuthal angles of molecules i and j. In this equation, 10 is the permittivity of free space. We used potential parameters suggested by Mo ̈ller and Fischer [2]: 1=kB 1⁄4 125:317 K; s 1⁄4 3:0354 A􏴤 ; L 1⁄4 l=s 1⁄4 0:699 and Q*2 1⁄4 Q2=ð4p10s5Þ 1⁄4 3:0255: SIMULATION DETAILS The fluctuation method based on Monte Carlo simulations in the isothermal – isobaric ensemble was used. Simulations containing 500, 864 and 1320 molecules, initially placed on a face-centered cubic lattice, were performed at low and high temperature, and it was verified that the results were independent on the size of the system. Therefore, the results in this work correspond to a total of N 1⁄4 500 molecules. Periodic boundary conditions and minimum image conventions were applied. Simulations were orga- nized in cycles. Each cycle consisted of N attempts to displace or rotate a randomly chosen molecule and an attempt of volume change. A variable spherical cut-off radius rc, equal to half the box length was used (e.g. at 330.39 K and P 1⁄4 2:5 MPa; rc 1⁄4 15:5s 1⁄4 4:7 nm; and at 330.39 K and P 1⁄4 72:3 MPa; rc 1⁄4 5:4s 1⁄4 1:6 nm), and long-range corrections were recalculated after each volume Representation of the 2CLJQ model. (a) Each molecule In Eq. (13), rab is one of the four Lennard – Jones site-to-site distances (see Fig. 1a) where a counts the two sites of molecule i, and b counts those of molecule j. The Lennard – Jones parameters s and 1 represent the size of each site and the well depth of the potential energy, respectively. The contribution to the potential energy due to the quadrupole – quadrupole interactions is given by

PDF Image | Thermal Properties of Supercritical Carbon Dioxide

thermal-properties-supercritical-carbon-dioxide-003

PDF Search Title:

Thermal Properties of Supercritical Carbon Dioxide

Original File Name Searched:

Thermo_Prop_scCO2.pdf

DIY 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 | RSS | AMP