Research — Auto Demo · Precomputed (draft, unvalidated)

Liquid loop: lose a CDU — auto

No controls here: six short stories play on their own. A spare CDU keeps the row inside what you entered. One survivor can run near the cited velocity limit. A survivor below the demand leaves a negative margin while its leg looks calm. A leg over the limit is fixed by the next size or by parallel runs. A 2.5 in leg has no cited limit and is never a pass. Use Pause, or the story and step buttons, to stop on any frame.

Story

Liquid loop · plan view of one rack row

passtight (display band)over the cited limitno cited limit (hatched, never a pass)unit outcited limit ticknominal level, for comparison

Velocity is checked per CDU leg (the trunk pipe between a CDU and the manifold), not on the manifold; the manifold arrows are schematic. Gauges run on a plain 0 to 5 m/s drawn axis. L/m is litres per minute. Supply 30 C, return 40 C and all kW are illustrative placeholders.

The same row · isometric

Leg diameter ladder · after losing one unit

The same row at each exported leg size, read from the grid (circles drawn to scale).

Every check at this step · the controlling row is highlighted

Rule column: the citation the data file gives for each check.

How the checks read it

Every check · before the loss, after the loss, after the fix

Required values are read from the data file. The table fills in as the story reaches each step. 'No cited limit' means not applicable, never a pass.

Precomputed results:every verdict, required value and margin on this page was computed by the real Python harness at export time and is played back from a data file. The page runs no harness logic and holds no standards tables, and it never interpolates between exported values. Not a live API call. Precomputed by the real functions aggregate_rack_heat_load, check_cooling_capacity_margin, evaluate_liquid_cooling_heat_dissipation, evaluate_pipe_velocity_for_flow_rate, propose_pipe_diameter_remediation and propose_parallel_pipe_remediation in thermal-calc-harness (recorded commit a5692d9), a v0.1 draft with no domain-expert review. Every kW, flow, temperature and diameter on this page is a round illustrative placeholder. The harness has no per-CDU failure function, so removing a unit, the flow the racks ask for, the proportional flow sharing among the running units, the cap at the survivors' rated flow, the "tight" display band (velocity at or above 80 % of the cited limit) and every comparison against the capacity you entered are this demo's own logic, tagged demo logic. Pipe-velocity limits are ASHRAE guidance reached only through secondary sources. Nominal 2 in to 3 in has no cited limit: not applicable, never a pass. Water properties are the harness's constants near 20 C, used at 30 to 40 C. Capacity is a nameplate comparison only; no pump curve is modelled. No catalog or product data is used. Domain maturity: starting inventory, not a completed review.Real functions this maps to:aggregate_rack_heat_load, check_cooling_capacity_margin, evaluate_liquid_cooling_heat_dissipation, evaluate_pipe_velocity_for_flow_rate, propose_pipe_diameter_remediation, propose_parallel_pipe_remediation.Not modeled: pump curves or flow-dependent capacity, pressure drop and the manifold itself (velocity is checked on each CDU leg only), an idle spare (every installed unit runs), the facility-water side, and any real site layout. The drawing is schematic.See also:Liquid loop, interactive with free play · Power path N-1, hands-off · Cooling capacity margin, hands-off