Week 8 - Simulating Cyclone separator with Discrete Phase Modelling
Aim:- To perform analysis on cyclone separator and calculate the separation efficiency and pressure drop.
Objective:-
- To write a few words about any four empirical models used to calculate the cyclone separator efficiency.
- To perform an analysis on a given cyclone separator model by varying the particle diameter from 1 μm to 5 μm and calculate the separation efficiency in each case. Discuss the results. [Use both the velocity's as 3m/sec.]
- To perform an analysis on a given cyclone separator model by varying the particle velocity from 1 m/sec to 5 m/sec and calculate the separation efficiency and pressure drop in each case. Discuss the results. [Use particle diameter size as 5 μm for all cases & keep flow velocity same as particle velocity]
Boundary Conditions:-
Inlet and wall:- Reflect
Outlet(Top):- Escape
Outlet(Bottom/dustbin) - Trap
Emperical model used to calculate the Cyclone seperator Efficiency are:
In this case we will use Lapple method to find out the efficiency of the cyclone seperator. which is total number of particles trapped by total number of particles present.
STEPS TO FOLLOW FOR MODELLING AND DEVELOPING MESH FOLLOWED BY PREPROCESSING ARE GIVEN BELOW.
THE STEPS ARE AS FOLLOWS.
STEP 1- FIRST WE NEED TO OPEN SPACE CLAIM
STEP 2- THEN WE NEED TO IMPORT THE CYCLONE SEPERATOR STEP FILE INTO THE SYSTEM WHICH WILL GENERATE THE BODY.
STEP 3- NOW WE HAVE TO USE THE REPAIR EDGE TOOL TO REPAIR ANY DUPLICATE EDGES.
STEP 4- NOW WE NEED TO EXTRACT THE VOLUME OUT OF THIS 3 D MODEL
STEP 5- CLOSE THE SPACECLAIM INTERFACE
STEP 6- NOW OPEN MESHING.IN MESHING WE GIVE A MESH SIZE STANDARD OF 10 mm AND GENERATE THE MESH. WE LIMIT THE SIZE OF TH MESH SINCE WE ARE USING THE ACADEMIC LISENCE OF ANSYS. HERE WE WILL NAME 1 INLET AND TWO OUTLETS USING NAME SELECTION.
STEP 7-NOW OPEN THE SETUP WINDOW AND LOOK FOR THE MESH WHICH WILL LOOK AS BELOW.
STEP 8- WE WILL USE A PRESSURE BASE SOLVER HERE WITH STEADY STATE ANALYSIS. WE WILL USE K-EPSILON TURBULANCE MODEL. WE WILL BE APPLYING GRAVITY IN NEGETIVE Y DIRECTION AT THE MAGNITUDE OF 9.81m/s^2
STEP 9- WE WILL BE USING RNG VERSION OF K-EPSILON MODEL OF VISCOUS FLOW AND SWIRL DOMINATED FLOW WILL BE TICKED IN.
STEP-10 HERE WILL BE ADDING THE DISCRETE PHASE. AS FOLLOWS.
STEP 11- WE WILL NOW CLICK ON THE INJECTIONS AND CLICK ON SET. THE FOLLOWING WINDOW WILL APPEAR
STEP 12- WE WILL SELECT AN INERT MATERIAL PREFERABLY ANTHRACITE AND WILL SELECT INLET AS THE POINT OF ENTRY.
STEP 13- UPTILL HERE ALL THE DRILL WILL BE SAME. BUT HERE WE ARE EXPERIMENTING INSANCES BY by varying the particle diameter from 1 μm to 5 μm and calculate the separation efficiency in each case. Discuss the results. [Use both the velocity's as 3m/sec.] AND varying the particle velocity from 1 m/sec to 5 m/sec and calculate the separation efficiency and pressure drop in each case. [Use particle diameter size as 5 μm for all cases & keep flow velocity same as particle velocity]
IN THE DEMO WE ARE SHOWING 3M/S WITH 1MICROMETER PARTICLE DIAMETER.
STEP 14 : NOW WE WILL GO TO BOUNDARY CONDITION AND CHANGE THE INLET VELOCITY AS DESIRED i.e. 3M/S
STEP15: WE WILL INITIALIZE THE STANDARD VERSION AND FROM THE INLET AS THE PARTICLES ARE ENTERING FROM THAT REGION ITSELF.
STEP 16: AFTERWORD WE WILL CALCULATE THE EQUATION FOR ABOUT 600 ITERATION.
THE RESULTS ARE AS FOLLOWS.
INSTANCE 1: By varying the particle diameter from 1 μm to 5 μm and calculate the separation efficiency in each case. [Use both the velocity's as 3m/sec.]
CASE 1: PARTICLE 1 um AND VELOCITY 3m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 35.
TOTAL PARTICLES:71
EFFICIENCY:35/71*100=49.29%
CASE 2: PARTICLE 3 um AND VELOCITY 3m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 103.
TOTAL PARTICLES: 124
EFFICIENCY:103/124*100=85.123%
CASE 3: PARTICLE 5 um AND VELOCITY 3m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 112.
TOTAL PARTICLES: 124
EFFICIENCY:112/124*100=90.32%
INSTANCE 2: By varying the particle velocity from 1 m/sec to 5 m/sec and calculate the separation efficiency and pressure drop in each case. [Use particle diameter size as 5 μm for all cases & keep flow velocity same as particle velocity]
CASE 1: PARTICLE 5 um AND VELOCITY 1m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 12.
TOTAL PARTICLES: 124
EFFICIENCY:12/124*100=9.677%
CASE 2:PARTICLE 5 um AND VELOCITY 3m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 112.
TOTAL PARTICLES: 124
EFFICIENCY:112/124*100=90.32%
CASE 3:PARTICLE 5 um AND VELOCITY 5m/s.
RESIDUALS:
PARTICLE TIME:
VORTEX FLOW:
THE TRAPPED PARTICLES ARE 122.
TOTAL PARTICLES: 124
EFFICIENCY:122/124*100=98.38%
INFERENCE:
1. HIGHER THE PARTICLE SIZE HIGHER IS THE SEPERATION EFFICIENCY OF CYCLONE SEPERATOR.
2.HIGHER THE VELOCITY OF THE PARTICLE HIGHER IS THE SEPERATION EFFICIENCY OF CYCLONE SEPERATOR.
3.HENCE THE SEPERATOR WILL WORK BEST AT HIGHER DIAMETER OF PARTICLE.