Platform / AcaysiaGEM

Geometry engine

AcaysiaGEM

A spatial simulation is only ever as good as the shape you run it in.

Real vessels are not boxes — they have dished bottoms, baffles, downcomers, sparger rings and nozzles set at awkward angles, and every one of those changes the answer. GEM builds that shape, proves it is fit to simulate before a GPU hour is spent on it, and hands it to AcaysiaDRT ready to run.

Geometry library
18
Parametric geometries, benchmark duct to full vessel
Boundary tags
100%
Boundary faces tagged, or the build fails
Wasted GPU hours
0
On a leaking domain

The model is the picture

Rendered from the solver's own geometry

Not a picture of a plant — the plant itself.

Twelve units, routed lines and procedural steel.

Authored parametrically and rendered straight from the same model the solver runs on. There is no separate marketing model to fall out of sync — when the design changes, the picture changes with it.

Render of a twelve-unit process plant built by AcaysiaGEM: stirred vessels, distillation columns, routed yellow piping and structural steel on a hardstanding. The same plant rendered in x-ray: vessel walls transmissive, showing distillation trays, downcomers, impellers and packing inside.

Figure — the twelve-unit plant Metal is the plant as equipment, standing on the hardstanding. X-ray is the same scene: the walls go transmissive and the internals the geometries already built — trays, downcomers, impellers, packing — are simply there. 3D model is the exported model itself, running in your browser at 147,710 triangles — the same geometry the solver meshes, one export flag on the plant above.

  • Two looks

    Equipment, or x-ray.

    One scene rendered twice. Nothing was modeled specially for the transparent version — the internals were always in the geometry, because the solver needs them there.

  • Fast

    Seconds, not hours.

    The twelve-unit plant renders in about 6 seconds on a GPU. Fast enough that a render is something you do while iterating, not a deliverable you schedule a day for.

  • Web-native

    Ship the model, not a screenshot.

    Output is a still image, an editable scene, or a 3D file a browser can open — usually the better answer, since it is the model itself rather than a picture of it.

  • Composable

    Drops onto a page.

    Renders come out on transparent backgrounds with the plant still standing on its own shadow, so it composites cleanly onto whatever sits behind it.

The idea

Fluid domain · tagged negative space

Model the space,
not the steel.

Ordinary CAD describes the vessel: the shell, the flanges, the weld prep. A solver does not care about any of that. It cares about the shape of the liquid.

GEM models that negative space directly, and labels its edges as it builds them. That is why its output drops into a solver without the usual translation losses.

  1. Inlet This face is where fluid enters.
  2. Wall That one is a wall — shell, dished bottom and baffles.
  3. Exclusion This volume is swept by an impeller and is not fluid at all.
  4. Outlet And this is where it leaves.
Cross-section of a stirred vessel The fluid domain drawn as tagged negative space: an inlet nozzle through the top head, wall boundaries on the shell, dished bottom and baffles, an impeller exclusion zone around the turbine, and an outlet nozzle in the bottom head. Dimension lines mark the parameters the vessel is built from: diameter D, liquid height H, impeller diameter d and clearance C. D H C d FLUID DOMAIN negative space INLET WALL EXCLUSION OUTLET
Diameter · liquid height · impeller · clearance Every face carries exactly one tag

Internals

What the solver sees, and what it doesn't.

Agitator shafts, turbines, drive motors, baffles and nozzle flanges can be carried for visual fidelity without polluting the physics. A rotating impeller is handed to the solver as the volume it sweeps, which is the honest representation of it.

Geometry library

18 geometries · 3 families

Eighteen shapes, three families.

From the ducts the solver is benchmarked on to the real equipment, internals and all.

Family Geometries What it is for
Flow domains6 Channel · cylinder in channel · backward-facing step · sudden expansion · serpentine mixer · lid-driven cavity Benchmark ducts — the shapes the solver is benchmarked on, where an analytic or published answer exists.
Inline components2 Tee mixer · orifice plate Round pipe fittings — blending at a junction, and pressure loss across a restriction.
Vessels10 Stirred tank · distillation column · bubble column · packed-bed reactor · fermenter · flash drum · decanter · cyclone · drum · horizontal separator The real equipment — internals and all, at the scale a plant actually runs.
Vessels / stirred tank Metal
Studio render of a stirred tank built by GEM: dished shell, drive motor on the top head and a flanged side nozzle.
Stirred tank. Shaft, turbine, drive motor, baffles and nozzle flanges are all here — carried for fidelity, and none of them confusing the solver about where the fluid is.
Vessels / distillation column X-ray
X-ray render of a distillation column revealing the stack of trays and downcomers inside the shell.
Distillation column, walls made transparent. The tray stack and downcomers are genuinely modeled, not implied by a texture — which is why a spatial solver can be asked what happens between them.

Parameter sweeps

Each geometry sweeps across its whole parameter range in the test suite, so a mis-tagged large impeller, a baffle poking through a dished bottom, or an unsealed vessel is caught automatically on any change — not discovered halfway through a run.

Process · the export is gated

Describe · Build · Check · Export

How a domain gets built.

Describe it, build it, check it, export it — nothing reaches the solver until the check has passed.

Each step exists because the alternative fails quietly rather than loudly.

  1. Describe · Parametric

    Dimensions, not drawings.

    A vessel is described by the numbers an engineer already has — diameter, liquid height, impeller ratio, clearance, nozzle positions — and rebuilt from them on demand. Changing a design means changing a number, not redrawing a model.

  2. Build · Tagged at build

    The builder knows what it built.

    Boundary faces get their meaning — inlet, outlet, wall, symmetry, exclusion — at the moment the builder creates them. No fragile post-hoc guessing about which surface was the inlet, and no selector language to get wrong.

  3. Check · Health check

    Fail on the desk.

    Watertight, every face tagged, one connected fluid, nothing protruding. Every domain has to pass its health check before it can be exported — the four checks.

  4. Export · Lattice-ready

    Straight into the solver.

    A validated domain converts into exactly what AcaysiaDRT consumes, in the solver's own conventions — no translation losses.

Step 03 · Health check

Runs before every export

Fail on the desk, not on the cluster.

The expensive failure in spatial simulation is not a wrong answer.

It is a run that consumes a night of GPU time and produces nonsense because the domain leaked. Every GEM domain has to pass a health check before it can be exported.

  • Watertight

    A real solid.

    Valid, watertight, a single connected body with positive volume. The check that catches a geometry which merely looks closed on screen.

  • No untagged faces

    Every boundary has a rule.

    Each boundary face must carry exactly one tag. An untagged face is a hole in the physics — a boundary the solver has no instruction for — and it leaks silently rather than erroring.

  • Nothing stranded

    One connected fluid.

    The fluid must be one region with no isolated pockets, every declared opening must actually reach it, and the domain must be sealed everywhere an opening does not exist.

  • Nothing protruding

    Internals stay inside.

    Anything declared as submerged has to genuinely sit within the fluid. When it doesn't, the check names the offending point rather than leaving you to find it in a render.

Grounded

Checked against real CAD.

Where a trusted reference part exists, GEM's model is regression-checked against it, so a simplified flow domain stays honest about the equipment it represents.

  • Volume
  • Surface area
  • Centroid
  • Inertia
  • Bounding box

Step 04 · Export

Build · check · hand off

Straight into the solver.

Build, check, hand off. Every domain has to pass its health check before it reaches the solver.

Export
Lattice-ready, three ways. A validated domain converts into exactly what the solver consumes. Where a geometry carries an exact mathematical description of its surface, the export uses it, giving sub-cell accuracy at curved walls instead of a staircase.
Contract
No translation losses. The export encodes the solver's own conventions directly, pulled from its source rather than reimplemented — the class of mismatch that produces a simulation which runs happily and means nothing.
Downstream
Then it's a DRT run. From there it is an AcaysiaDRT job: solved flow, transport, and the chemistry that AcaysiaRT supplies per cell.
In the app
Without the toolchain. AcaysiaCORE brings this into the browser — pick a geometry, set the parameters, see it in 3D, check the regions, and export it for a run without installing anything.

Channel · 100 × 20 × 20 mm · as the solver receives it

Schematic

A channel domain after export A rectangular channel drawn as lattice cells: a row of solid wall cells along the top and bottom, a column of inlet cells at the left end, a column of outlet cells at the right end, and fluid cells between them, with flow running from inlet to outlet.
  • Fluid
  • Wall · solid
  • Inlet
  • Outlet

Health check · before export

  1. Watertight
  2. Every face tagged
  3. One connected fluid
  4. Nothing protruding
Every lattice cell carries exactly one flag, and the solid mask is written in the solver's own cell order. Nothing is handed to AcaysiaDRT until all four checks have passed.

Plant assembly

The physical counterpart of a Rete flowsheet

One vessel is the primitive.
A plant is the point.

The same machinery that places one vessel places thirty of them.

GEM grows from independent geometries into a laid-out, connected, named plant.

Render of a thirty-unit process plant: four parallel process trains with pipe racks, routed yellow lines and structural steel on a hardstanding.
Figure — the thirty-unit plant Thirty units, four parallel trains, 1.6 million triangles — spanning 105 × 172 meters of plot. Built from eight distinct designs, because identical units share one underlying shape.

  • Plot plan

    Place and orient.

    Units are positioned as a plot plan, each placed unit carrying its boundary tags along with it — the detail that separates a real assembly from a pile of shapes that lost their meaning when they moved.

  • Piping

    Routed, not drawn.

    Connections between units are routed through the plant as real line work rather than sketched, with nozzle-to-nozzle port matching and collision awareness.

  • Structure

    Racks, steel and access.

    Pipe racks, supports and access structure come with it, so what you are looking at reads as a plant rather than as vessels floating in space.

  • Cheap by design

    Thirty units, eight builds.

    Identical units share one underlying shape, so a thirty-unit plan costs eight builds and not thirty. That is what makes assembling a whole plant routine instead of an overnight job.

AcaysiaGEM

Geometry → AcaysiaDRT

Start from your geometry.

Talk to us about modeling your vessels — and what changes when the simulation runs in the real shape instead of an idealized one.

Book a discovery call