Store Slowly. Spend at Two Kilograms a Second.

A gas-turbine test article swallows air at a scale no sensible compressor plant can deliver live: 2.00 kg/s of conditioned, regulated air made in real time would require a megawatt-class machine that sits idle between tests. Neometrix’s ground air supply station solves this the way every good high-demand system does: store slowly, spend fast. A screw-compressor plant charges an open-yard air storage farm to 13 kg/cm² in 20 minutes, then blows it down to the test article at 2.00 kg/s, regulated to 4 kg/cm² ±0.35, for five starts back-to-back — dry to −65 °C dew point, oil content below 0.01 ppm, with an independent oil-free instrumentation air system running alongside.

Average Power In, Peak Flow Out

The fill loop uses three screw compressors — two working, one standby — each rated for at least 13 kg/cm²(g) and 36 m³/min of free air at the hardest honest ambient condition (40 °C and 100% humidity simultaneously, not the pleasant-day number a brochure might quote). Each compressor runs through its own 5 m³ receiver, filtration and blower-reactivation drier, charging the open-yard cylinder farm from zero to 13 kg/cm²(g) inside 20 minutes on no more than 700 kW.

The Spend Loop Never Lets the Article Go Hungry

The test article is fed from storage, one cell at a time, through regulation that holds 4 kg/cm²(g) within ±0.35 while the farm’s pressure continuously falls — two minutes of continuous 2.00 kg/s flow per start, five starts in succession with two-minute gaps between them, and the article’s inlet never drops out of band throughout. One compressor keeps replenishing storage throughout, running on an islanded site generator at no more than 400 kW without disturbing the generator’s frequency.

Compressor FAT at the Maker’s Works

The entire 20-minute fill promise lives or dies on real, proven compressor performance, so factory acceptance testing — rated pressure, flow and shaft power demonstrated at the manufacturer’s own works — is carried in the scope of supply before anything ships. The performance demonstration is then repeated on site, fully integrated, at handover, rather than trusting the factory numbers alone.

Instrument Air Stays Alive While Main Air Is Spent

A separate instrumentation air system runs alongside the main station: two reciprocating, non-lubricated, oil-free, water-cooled compressors at ≥40 kg/cm²(g) and ≥150 CFM each, with their own driers, filters and storage — so the gauges and instruments keep reading precisely even when the main air farm is roaring down during a test.

Where Blow-Down Stations Actually Fail

Not on the first start — on the fifth. A storage farm sized only for one heroic single-run demonstration passes its commissioning trial and then quietly starves the real test programme: the fourth start begins from a lower shelf of stored pressure than intended, the regulator runs out of upstream authority to hold the band, and the article’s inlet sags out of specification mid-test. That’s precisely why the five-start duty cycle is the entire design’s spine, and why farm volume is a submitted engineering calculation rather than a brochure line item.

Frequently Asked Questions

Why can’t a gas-turbine test cell just use a compressor plant that produces air in real time, rather than a storage-and-blow-down system?
Because the peak air demand during an actual engine test run is dramatically higher than the average demand across the full test cycle. A gas-turbine test article can consume air at roughly 2 kilograms per second during a run — delivering that flow rate live, continuously, would require a compressor plant sized in the megawatt class that then sits almost completely idle between test runs. That’s an enormously wasteful and expensive way to solve the problem. Instead, storing air slowly over time using a much smaller, continuously-running compressor plant, then releasing that stored air in a short, high-flow burst when a test actually runs, lets a comparatively modest compressor plant support test demands that would otherwise require far more installed power.

Why does a ground air supply station need to prove it can handle five consecutive test starts rather than just one?
Because a storage farm that looks perfectly adequate for a single demonstration test can still fail a real test programme, which typically involves multiple consecutive engine starts in sequence. Each start draws down the stored air pressure further. If the farm’s storage volume was only sized (or only tested) against a single heroic run, the third, fourth or fifth consecutive start in a real sequence can begin from a lower starting pressure than the system was actually designed to handle — at which point the pressure regulator can run out of upstream pressure “authority” to hold its target band, and the test article’s air supply sags below specification mid-test, potentially compromising the test data or the test itself. Designing and proving the system against a defined multi-start duty cycle — not just a single successful run — is what actually guarantees it will support a real test campaign.

Get In Touch

For full specifications, RFQs, or a technical discussion about the ground air supply station:
– Product page: Ground Air Supply Station
– Email: [email protected]
– Phone: +91-7777-876-876