CryoPulseCRYOPULSEBack to the car

THE FIRST COLD-FLOW DEMONSTRATOR / CF-1.1

Can colder air
flow faster?

20°C and 0°C. The same copper channel.
The same pressure. A test we can build.

Digital design · Hardware measurements: 0
↓

THE TEST ARTICLE

Small enough to build.
Specific enough to test.

Machined copper, gentle inlet and outlet adapters, four wall probes and two temperature-controlled plates.

Exploded render of the actual copper channel CAD, with lid, four fasteners, probes, two cold-plate allocations and tapered adaptersSTEP-derived geometry Unbuilt
The copper and airflow path are dimensioned CAD. The four 1 mm probes have a selected catalogue specification. Cold plates remain installation allocations; the assembled rig still needs fabrication review and calibration.
1.00mm

Channel gap

19mm

Internal width

50mm

Copper channel length

60.21Pa

Total-to-static pressure target

Download the bench design ↘Open the dimensions ↗Native STEP ↘

CHANGE ONE CONDITION

Keep the pressure.
Change the temperature.

Cooling changes air density and viscosity. We measure whether their combined effect increases mass flow through this channel.

INLET AIR 20°CCHANNEL WALL 20°COUTLET PRESSURE Recorded separately
Gentle entryCopper coreStraight outlet
Same geometry · Same pressure head · Dry airSchematic motion. Channel height is enlarged.
NUMERICAL STUDYUnder review

The full-gap warm/cold calculations are being checked for stable flow, grid sensitivity and heat balance.

PHYSICAL RESULTNot measured

The hardware has not been built. A calculation will not be presented as a measurement.

WHAT THIS CAN ESTABLISHOne flow effect

A positive experiment supports the measured channel conditions. The car’s performance requires its own evidence.

INSIDE THE NUMERICAL EXPERIMENT

Follow the temperature
through the channel.

These colours come from saved CFD temperature fields. Both runs use the same pressure head. The copper wall changes from 20°C to 0°C.

20°C wallWarm reference
Actual CFD mid-plane snapshot: air remains close to 20 degrees Celsius through the warm channel
0°C wallCooled channel
Actual CFD mid-plane snapshot: air cools next to the copper walls and through the narrow core before entering the expanding outlet
EntryCopper coreStraight outlet
Air temperature0°CTemperature scale from dark blue at zero to gold at twenty degrees Celsius20°C

Saved field snapshots, with the gap enlarged 8× for visibility. Grid, time-step and stable-window checks are continuing. This is numerical work; the prototype has not been measured.

Open the scientific figure ↗Field origin and checksums ↗

EXPLORE THE MECHANISM

Turn the temperature down.
Watch the calculation change.

An independent, simplified model predicts a flow increase. Its heat-transfer and duct-loss coefficients are inputs you can change. This is a calculation, awaiting the experiment.

Calculated bulk air temperature °C

2010002550Distance through the copper channel (mm)
Bulk air Channel wallOutlet —
CALCULATED MASS-FLOW CHANGE—

Compared with the same model at a 20°C wall.

—L/min at the warm inlet

—W of heat removed

Warm —
Selected wall —

Developed rectangular-duct resistance, ideal-gas density and temperature-dependent viscosity, with a constant Nusselt number. The real prototype has three-dimensional developing flow. The assumed coefficients are not fitted to its CFD. Cooling-system power is additional.

Compare all nine assumptions ↗Equations, inputs and checks ↗Run the reference calculation ↘

THE MEASUREMENT PLAN

A fair comparison,
before the first run.

The same article runs warm and cold in twelve paired blocks. Half begin warm; half begin cold. The order is fixed before measurements.

FROZEN TEST ORDERW = 20°C · C = 0°C

Each square is a thermal block, not a sensor sample. Sixty seconds of readings produce one run mean.

01

Measure the actual conditions.

Four calibrated wall probes, inlet temperature, dry-air dewpoint, mass flow and independent pressure readings.

02

Keep the controls in the record.

Leak blank, warm–warm comparison and open bypass. Failed runs stay visible with their rejection reasons.

03

Make the uncertainty count.

The paired interval must clear the stated instrument bounds. More sensor samples do not become more independent experiments.

Read the frozen protocol ↗Download the analysis ↘See the measurement fields ↗

THREE SEPARATE ACCOUNTS

Flow, heat and electrical power.

A flow increase is useful information. Its energy cost must be measured alongside it.

The blower supplies pressure.

Record the pressure head and flow. Pressure work is Δp × volume flow; blower electrical input is measured separately.

Pressure and flow instruments

The controller removes heat.

Hold the actual wall temperature. Record cooling-system, pump and heater input instead of treating the cold boundary as free.

Wall probes and power meters

The meter measures mass flow.

Compare warm and cold under the recorded conditions. A compact multi-channel core and its manifold will need a separate model and test.

Calibrated low-drop flow meter

THE EVIDENCE RECORD

Open the design.
Inspect the result.

The files below separate the prototype specification, numerical verification and future measurements.

Source material

Fluke 1 mm temperature probe data ↗Viscosity model ↗KME Cu-OFE material data ↗NIST copper properties ↗Furness pressure instrument data ↗Alicat flow instrument data ↗

Instruments are candidates, with catalogue bounds carried into the protocol. Final calibration and as-built dimensions govern the experiment.