CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > CD-adapco

Regarding Coefficient-of-Discharge of intake port

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   May 17, 2005, 02:00
Default Regarding Coefficient-of-Discharge of intake port
  #1
LeelaPrasad
Guest
 
Posts: n/a
Hi,

In STAR-CD how to find Coefficient Of Dischage(Cd) of intake port/manifold.Actually i did steady flow analysis for induction stroke now i want to find out Cd for inlet manifold ....kindly guide me how to get Cd.

With Regrds.

LeelaPrasd.
  Reply With Quote

Old   June 15, 2005, 10:34
Default Re: Regarding Coefficient-of-Discharge of intake p
  #2
Michele
Guest
 
Posts: n/a
hi

you can find what you need at http://www.adapco-online.com/adapco_...frontpage.html

anyway it follows a copy of what you requested. bye

michele

***************************************

(5) Calculation of Discharge and Swirl Coefficients: ! !-Calculation of Discharge Coefficient (CD): ! *CLEAR *SET MASS 0.085 $!-Inlet Mass Flow Rate (kg/s) *SET DVAL 0.04683 $!-Valve Diameter (m) *SET GAMMA 1.4 $!-Ratio of specific heats *SET LIFT 0.01225 $!-Valve Lift (m) *SET M 28.96 $!-Molecular weight (kg/kmol) *SET REG1 1 $!-Inlet boundary region number *SET REG2 2 $!-Outlet boundary region number *SET SCAL 0.001 $!-Geometry Scale Factor ! ! CD = MA / MTH ! MA = Actual Mass Flow Rate ! MTH = Theoretical Mass Flow Rate ! = AREF * PTOT * SQRT [ A1 * A2 * A3 ] ! ! AREF = 2 * PI * DVAL * LIFT (= Reference Area (m**2)) ! ! A1 = 2 * GAMMA / ( (GAMMA-1) * R * TTOT ) ! ! A2 = (P/PTOT)**(2/GAMMA) ! ! A3 = 1 - (P/PTOT)**((GAMMA - 1)/ GAMMA) ! ! P = Outlet Static Pressure ! ! PTOT = Plenum inlet total pressure ! ! TTOT = Plenum inlet total temperature ! ! R = gas constant ! *SET,MA,MASS *SET,PI,3.14159 *SET,AREF,2.0 * PI * DVAL * LIFT *SET,R,8314.4 / M CSET,NEWS,FLUID ! !-Get Cell Data: ! LOAD,, OPER,CLEAR,1,6 OPER,GETC,PSTA,1,ABSO OPER,GETC,PTOT,2,ABSO OPER,GETC,TTOT,3,ABSO OPER,GETC,VOLU,4 OPER,SMULT,SCALE * SCALE * SCALE 4 4 ! ! Step 1 - Calculate Quantities at Outlet: ! BSET,NEWS,REGI,REG2 VSET,NEWS,BSET CSET,NEWS,VSET,ANY CSET,SUBS,FLUID ! ! Calculate Volume Averaged Static Pressure P: ! OPER,MULT,1,4,6 *GET,VOLU,RTOT,4 *GET,P,RTOT,6 *SET,P,P / VOLU ! ! Step 2 - Calculate Quantities at Inlet: ! BSET,NEWS,REGI,REG1 VSET,NEWS,BSET CSET,NEWS,VSET,ANY CSET,SUBS,FLUID ! ! Calculate Volume Averaged Total Pressure PTOT: ! OPER,MULT,2,4,6 *GET,VOLU,RTOT,4 *GET,PTOT,RTOT,6 *SET,PTOT,PTOT / VOLU ! ! Calculate Volume Averaged Total Temperature TTOT: ! OPER,MULT,3,4,6 *GET,VOLU,RTOT,4 *GET,TTOT,RTOT,6 *SET,TTOT,TTOT / VOLU ! ! Step 3 - Calculate Coefficient: ! *SET,A1,GAMMA - 1 * R * TTOT *SET,A1,2 * GAMMA / A1 *SET,A2,2 / GAMMA *SET,A2,P / PTOT ** A2 *SET,A3,GAMMA - 1 / GAMMA *SET,A3,P / PTOT ** A3 *SET,A3,1 - A3 *CALC,MTH,AREF * PTOT,SQRT,A1 * A2 * A3 *SET,CD,MA / MTH *LIST,CD

! !-Calculation of Impulse Meter Swirl Coefficient (CS): ! *CLEAR *SET,BORE,0.0934056 $!-Bore Diameter *SET,CSYS,78 $!-Cylindrical Coordinate System for Cylinder *SET,GAMMA,1.4 $!-Ratio of specific heats *SET,MASS,0.085 $!-Mass flow rate *SET,REG1,1 $!-Inlet Boundary Region Number *SET,SCALE,0.001 $!-Geometry Scale Factor *SET,M,28.96 $!-Molecular weight (kg/kmol) SPOINT,0,-92,0 $!-Section location (PROSTAR units) SNORM,0,1,0 LOCAL,78,CYLI,0,0,0,0,-90,0 ! ! CS = 8 * T / MA / VREF / B ! ! Where: ! ! T = SUM [R * VW * DENS * VA * AN] = Torque ! ! SUM = Summation over all cells at section location ! R = Radius of centroid of cell I ! VW = Tangential velocity in cell I ! DENS = Density in cell I ! AN = Area of cell normal to cylinder axis (m^2) ! VA = Axial velocity through cell I ! MA = Mass flow rate through port (kg/s) ! B = Cylinder bore diameter (m) ! VREF = Reference velocity (m/s) ! = SQRT [ A1 * A2 * A3 ] ! ! A1 = 2 * GAMMA / (GAMMA - 1) ! A2 = R * TTOT ! A3 = 1 - (P/PTOT)**((GAMMA - 1)/ GAMMA) ! ! PTOT = Plenum inlet total pressure ! P = Static pressure at section location ! TTOT = Plenum inlet total temperature ! R = Gas constant ! *SET,PI,3.14159 *SET,B,BORE *SET,MA,MASS *SET,R,8314.4 / M LOAD,, CSET,NEWS,FLUID OPER,CLEAR,ALL ! ! Step 1 - Determine Torque T ! ! Put radial distance in register 5: ! OPER,GETC,X,CSYS,5 OPER,SMUL,SCALE,5,5 ! ! Put tangential velocity sv (VW) and axial velocity sw (VA) ! in registers 2 and 6: ! PSYS,CSYS OPER,GETC,SV,2 OPER,GETC,SW,6 ! ! Make register 4 be the following product: R*VW*DENS*VA ! OPER,GETC,DENS,4 OPER,MULT,5,4,4 OPER,MULT,2,4,4 OPER,MULT,6,4,4 SUMM,CSET ! ! Put u,v,w in csys 1 in registers 1,2,3 respectively: ! PSYS,1 OPER,GETC,SU,1 OPER,GETC,SV,2 OPER,GETC,SW,3 SUMM,CSET OPER,PLLOAD SUMM,CSET ! ! Perform summation to calculate torque: ! INTEGRATE,CSET *GET,T,TAS ! ! Step 2 - Calculate Reference Velocity VREF: ! ! Calculate static pressure P at section location: ! GETC,ALL,P,ABSO INTE,CSET *GET,TAS,TAS *GET,TAREA,TAREA *SET,P,TAS / TAREA ! ! Calculate inlet total pressure PTOT: ! BSET,NEWS,REGI,REG1 VSET,NEWS,BSET CSET,NEWS,VSET,ANY CSET,SUBS,FLUID OPER,CLEAR,ALL OPER,GETC,PTOT,1,ABSO OPER,GETC,TTOT,3,ABSO OPER,GETC,VOLU,4 OPER,SMUL,SCALE * SCALE * SCALE,4,4 OPER,MULT,1,4,6 SUMM,CSET *GET,VOLU,RTOT,4 *GET,PTOT,RTOT,6 *SET,PTOT,PTOT / VOLU ! ! Calculate inlet total temperature TTOT: ! OPER,MULT,3,4,6 SUMM,CSET *GET,VOLU,RTOT,4 *GET,TTOT,RTOT,6 *SET,TTOT,TTOT / VOLU ! ! Calculate reference velocity VREF: ! *SET,A1,GAMMA - 1 *SET,A1,2 * GAMMA / A1 *SET,A2,R * TTOT *SET,A3,GAMMA - 1 / GAMMA *SET,A3,P / PTOT ** A3 *SET,A3,1 - A3 *CALC,VREF,1.0,SQRT,A1 * A2 * A3 ! ! Step 3 - Calculate Coefficient: ! *SET,CS,8 * T / MA / VREF / B *LIST,CS

  Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
discharge coefficient thomas CFX 11 May 2, 2013 15:02
discharge coefficient abudaniell FLUENT 3 April 21, 2013 08:31
coefficient of discharge MADANI SYED CD-adapco 1 January 4, 2006 05:46
discharge coefficient for aeroengine inlet Friederike FLUENT 0 September 30, 2003 14:46
turbulence model for intake port of an engine? Nyquist CD-adapco 0 May 23, 2003 03:52


All times are GMT -4. The time now is 17:56.