Pump Modeler Template Documentation

CONTENTS USER INTERFACE AND WORKFLOW... 4 STEP 1: IMPORT GEOMETRY... 5 IMPORT GEOMETRY... 5 STEP 2: PORTS DEFINITION... 6 INLET FACE... 7 OUTLET FACE... 7 INLET PORT BODIES... 7 OUTPORT BODIES... 7 STEP 3: CORE DEFINITION... 8 # OF TEETH ON INNER GEAR... 9 CORE TOP FACE... 9 CORE BOTTOM FACE... 9 CORE INNER GEAR FACES... 9 CORE OUTER GEAR FACES... 9 STEP 4: MESH SETTINGS...10 INTERFACE FACES FROM IN AND OUTPORT... 10 MESH DIVISIONS IN CORE GAP... 10 MESH DIVISIONS ALONG ROTATIONAL DIRECTION... 11 MESH DIVISIONS ALONG Z-DIRECTION... 12 STEP 5: MESH VERIFY...12 STEP 6: SOLVER SETTINGS...13 Page 2 of 17

CORE SPEED (RPM)... 13 PRESSURE AT INLET... 13 PRESSURE AT OUTLET... 13 WORKING FLUID... 13 VAPOR TYPE... 14 # CORES FOR FLUENT RUN... 14 LAUNCH FLUENT... 15 CUSTOM REPORT... 15 MASS FLOW RATE CHART... 16 ANIMATION OF PRESSURE... 17 ANIMATION OF GAS-VOF... 17 Page 3 of 17

User Interface and Workflow A custom wizard guides the workflow. This wizard can be access from Workbench (WB) page under ACT Start Page tab. Figure 1: Project Page wizards and PumpModeler wizard PumpModeler wizard includes 6 steps to setup the Gerotor Pump simulation using ANSYS DM/AM as pre-processing tools, ANSYS Fluent as solver and ANSYS CFDPost as post-processing tool. Page 4 of 17

Step 1: Import Geometry Import Geometry Select appropriate geometry file to import it into project. Geometry selected should have following geometrical conditions. It should contain flow-volume of inlet-port, outlet-port and core. Rotation of the gears should be along positive Z axis in the counter-clockwise direction. The center of the inner gear should be at (x=0, y=0). The axis of outer gear should be passing through a negative X coordinate value. The pump core should be a single solid body. Error! Reference source not found. shows project details for Step1 of the P umpmodeler wizard. After selecting the geometry file click on Next button from the wizard. This will create a fluid Flow system and imports the geometry. It also opens DesignModeler for next step inputs. Figure 2: Step 1 project page details Page 5 of 17

Step 2: Ports Definition This step has 4 input components representing pressure inlet faces, pressure outlet faces, inport bodies and outport bodies. A custom wizard in ANSYS DesignModeler, shown in Figure 3 and Figure 4: Step 1 Properties in DesignModeler guides the user through the process of creating named selections like inlet, outlet, inport and outport. User will be able to select different faces and bodies for respective conditions. Figure 3: Custom Wizard in DesignModeler Page 6 of 17

Figure 4: Step 1 Properties in DesignModeler Inlet Face Select appropriate faces from inlet port for inlet boundary conditions of the pump. Once selection is done click on Apply button from same section. This will add selected face as inlet face this boundary condition. User can select multiple faces here. Outlet Face Similar to inlet face, please select faces for pressure outlet boundary condition. User can select multiple faces here. Inlet Port Bodies Select bodies which represent intake port of the pump system. And click Edit and then Apply button from wizard section for inport bodies. User can select multiple bodies here. Outport Bodies Similar to inlet port bodies, please select bodies representing outport condition. Page 7 of 17

User can select multiple bodies here. After setting all the properties correctly, click on Next button from wizard panel. Operations are automated to create different named selections of ports. Figure 5 shows the named selection features added to DesignModeler tree. Step 3: Core Definition Figure 5: After end of Step 2 operations This step has 5 input components representing number of gear teeth, top, bottom, inner and outer faces of core body. A custom wizard in ANSYS DesignModeler, shown in Figure 6 guides the user through the process of adding named selections for core body. Figure 6: Step 2 Properties in DM Page 8 of 17

# of teeth on inner gear Enter the number of teeth on inner gear in this field. It should be more than 0 at any condition. Core Top Face Select core top faces from core body and assign to this property. Core Bottom Face Similarly, select core bottom faces from core body and assign to this property. Core Inner Gear Faces Select inner faces of the core which are belong to inner gear (wet surfaces of inner gear with core fluid). Core Outer Gear Faces Select outer faces of the core which are belong to outer gear (wet surfaces of outer gear with core fluid). After setting all the properties correctly, click on Next button from wizard panel. Operations are automated to create different named selections of core along with decomposition of core body in predefined manner. Figure 7: After end of Step 3 operations Page 9 of 17

Step 4: Mesh Settings This step has 4 input components, first component is for selecting the faces from ports to define interfaces, and other 3 are to set the custom mesh settings for core body. A custom wizard in ANSYS Meshing, shown in Figure. Figure 8: Step 3 Properties in Meshing Application Interface Faces from In and Outport Please select top and bottom faces of ports (inport and outport) which are going to connect with core top and bottom faces for interface definition. Mesh Divisions in Core Gap Figure 9: Details view of geometry component Number of mesh divisions between inner and outer gear clearance see Figure 10. Page 10 of 17

Figure 10: Creating MRF Mesh Divisions along Rotational Direction Number of mesh divisions for each sector of the core see Figure 101. Figure 11: Flow simulation inputs Page 11 of 17

Mesh Divisions along Z-Direction Number of mesh divisions along Z direction of the core see Figure 102. Figure 12: Flow simulation inputs After setting all the properties correctly, click on SUBMIT button from wizard panel. Operations are automated to create different named selections for core and ports. It also creates the specific mesh settings required for core. Then it proceeds to create mesh. Step 5: Mesh Verify In this step, mesh quality is reported if mesh generation is successfully from Step 4. For example here Element Count, Max. Aspect Ratio, Max. Skewness and Min. Orthogonal Quality is reported for generic gerotor pump. Figure 13: Accessing Report Page 12 of 17

Click on Next button from wizard panel to proceed to next step. This operation will export the profile data (inner gear and outer gear) from mesh which are required for fluent setup. Step 6: Solver Settings Two monitors are included in the report to check convergence. convergence level is necessary to achieve accuracy in results. Ensuring good Figure 14: Residual Monitors Core Speed (RPM) The rate at which core of the pump rotates in (revolutions per minute). Pressure at Inlet Pressure at inlet mentioned in Pa. Pressure at Outlet Pressure at outlet mentioned in Pa. Working Fluid This is auto populated list from XML file and fluid properties are set based on values from XML. Presently template includes 2 fluids in the list, but user can define the additional entries in XML file in installation directory. Page 13 of 17

Vapor Type Behavior of the vapor is defined using this dropdown selection. We have 2 options here Ideal Gas and Constant Density. # Cores for Fluent Run The number of cores has been set to 8 by default. This can be changed to lower or higher number depending on the availability of parallel cores on the computing machine used and parallel Fluent licenses. Higher number of cores will help in getting faster results. For a typical size of the problem using Mixing Template, the maximum number of cores that will give good speedup is about 64 cores. So the range for number of cores is from 2 to 64. But before setting this input, please check the availability of the compute resource and parallel license. Flow Iterations and Time step size are calculated based on RPM input. Generally we run the simulation for 2 revolutions of the pump core. The default value is set to 2880. This value is sufficient for most of the cases to reach repetitive trend. Page 14 of 17

Launch Fluent Your analysis is now ready; you can directly launch it by clicking on Update in your solution component. Custom Report A custom report gets generated CFD-Post using a session script. Once your calculation is over you can generate your report using update, or you can add components to it before generation. Page 15 of 17

The report is an HTML file, save as project_files\dp0\fff\post\report\report.html; to be opened in Mozilla Firefox. This report contains following entities: Mass Flow Rate Chart Page 16 of 17

Animation of Pressure Animation of Gas-VOF Page 17 of 17