HPLC Fluid Visualizer
Flow path
Drag components to arrange them. Select a component or tube to edit it. Double-click a valve to switch it.
System properties
| Pump | Backpressure (bar) | Band broadening, σ (µL) | Gradient delay (min) | Flow path |
|---|
Calculated at the composition with the highest viscosity in each pump’s programmed solvent range. Gradient delay includes the pump and tubing up to the first column, including its preheater.
Using the fluid visualizer
Select a part from the toolbar, move its translucent preview onto the grid, and click to place it. Press Escape to cancel. On a keyboard, focus the diagram, use the arrow keys to position the preview, and press Enter to place it. Then choose Connect tubing and select the two ports to join. Select blank space between ports to add bends; press Escape or turn off Connect tubing to cancel. Each port accepts one tube. Connected ports have a filled center and an outer ring; open ports are hollow. Components and tubing bends snap to the visible grid, while tube ends attach directly to their ports. Tubing can connect two ports of the same valve to form a sample loop.
Drag a component to move it. Select a tube and drag its square bend handles to change its route, or use Reset route. Drawing length does not set physical tubing length: enter the length or volume in Properties. Drag blank space to pan; use the mouse wheel or zoom buttons to zoom. On a keyboard, focus a component or port and press Enter to select it; use arrow keys to move a selected component.
Select a valve and choose Switch position, or double-click it on the diagram. Arrows show the flow direction from a connected source and update when valves switch. Blocked paths have no arrows. Colored tubing shows connectivity from each pump or autosampler at the current valve position; this is a steady-state flow-path diagram, not a time-resolved simulation of fluid mixing.
Save and open browser layouts as JSON files. The six supplied Java examples have been converted for this version. Other Java .lc files need offline conversion. Undo also restores a layout after loading an example or starting a new one.
How are system properties calculated?
Tubing pressure drop follows the Hagen–Poiseuille relationship, ΔP = 8ηLQ / (πr4). Column pressure is calculated from flow velocity, particle size, bed porosity, and viscosity. Water–methanol and water–acetonitrile viscosity depend on composition and temperature.
Tubing dispersion combines longitudinal diffusion and Taylor dispersion. Column dispersion uses the van Deemter relationship for plate height. Independent volume variances are added along each flow path; the reported band broadening is their square root. The model uses an average analyte molar volume of 120 cm³/mol in the Wilke–Chang diffusion relationship.
Gradient delay is the upstream volume divided by the pump flow rate. Detector and autosampler internal dispersion are not included. Valve pressure drop, delay, and dispersion include the rotor groove and two stator holes. A blocked path has no finite operating pressure in this model. These calculations are educational estimates.