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Bernoulli Equation Solver mechanism
The inspectable method record for Bernoulli Equation Solver, kept separate from implementation and qualification.
Model scope
The core ideal Bernoulli relation is correct, but the specification needs an explicit loss-inclusive equation and documented required inputs and constraints before it can receive PASS. The honest label should state that the loss-inclusive version is a steady incompressible energy equation with modeled head loss, not an inviscid equation.
- The ideal Bernoulli equation shown is standard for steady, incompressible, inviscid flow along a streamline, assuming no pump or turbine head.
- The phrase "(+ head loss term)" is ambiguous unless the equation explicitly states P1/(rho*g)+V1^2/(2*g)+z1 = P2/(rho*g)+V2^2/(2*g)+z2+h_L. A positive loss head must be added on the downstream side, or equivalently subtracted when solving for an upstream-to-downstream pressure.
- The claim "Any 5 of 6 terms at two points" is incomplete unless density, gravitational acceleration, and any head loss are known inputs. Some missing-term choices also require a physical-domain constraint, such as a nonnegative velocity magnitude.
- The formula does not include pump head or turbine-extraction head, so it cannot represent systems containing pumps or turbines without additional terms.
Units and conventions
- Use a single consistent unit system; the test vectors use SI units with pressure in Pa, density in kg/m^3, velocity in m/s, elevation and head loss in m, and g in m/s^2.
- rho is fluid density and is assumed constant between the two points.
- g is gravitational acceleration, taken as 9.81 m/s^2.
- P1 and P2 must use the same pressure reference, either both absolute or both gauge; only pressure differences affect the basic equation.
- For the loss-inclusive form, h_L is a nonnegative head loss in metres of the same fluid.
Inspectable vector
One of 4 source-bound review vectors:
{
"inputs": {
"rho_kg_per_m3": 1000,
"g_m_per_s2": 9.81,
"P1_Pa": 200000,
"V1_m_per_s": 3,
"z1_m": 5,
"V2_m_per_s": 5,
"z2_m": 2,
"hL_m": 0
},
"expected_outputs": {
"P2_Pa": 221430
},
"working": "Use P1/(rho*g)+V1^2/(2*g)+z1 = P2/(rho*g)+V2^2/(2*g)+z2+hL. Rearrange: P2 = P1 + 0.5*rho*(V1^2-V2^2) + rho*g*(z1-z2) - rho*g*hL. Compute: P2 = 200000 + 0.5*1000*(3^2-5^2) + 1000*9.81*(5-2) - 1000*9.81*0 = 200000 + 500*(9-25) + 9810*3 = 200000 - 8000 + 29430 = 221430 Pa."
}Failure boundary
BREAK_CLAIMED · SELF_FLAGGED
A zero-density input causes division by zero in the pressure-head terms, so the solver must reject the input or return undefined rather than a numeric pressure.
Other records
Sources and evidence
These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.
VERIFIED_LEDGER.jsonevidence-tranche4/tranche4-results.jsonBOUNDARY_HAZARD_CATALOG.json