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\/cm\u00b2 in 20 minutes, then blows it down to the test article at 2.00 kg\/s, regulated to 4 kg\/cm\u00b2 \u00b10.35, for five starts back-to-back \u2014 dry to \u221265 \u00b0C dew point, oil content below 0.01 ppm, with an independent oil-free instrumentation air system running alongside.<\/p>\n
The fill loop uses three screw compressors \u2014 two working, one standby \u2014 each rated for at least 13 kg\/cm\u00b2(g) and 36 m\u00b3\/min of free air at the hardest honest ambient condition (40 \u00b0C and 100% humidity simultaneously, not the pleasant-day number a brochure might quote). Each compressor runs through its own 5 m\u00b3 receiver, filtration and blower-reactivation drier, charging the open-yard cylinder farm from zero to 13 kg\/cm\u00b2(g) inside 20 minutes on no more than 700 kW.<\/p>\n
The test article is fed from storage, one cell at a time, through regulation that holds 4 kg\/cm\u00b2(g) within \u00b10.35 while the farm’s pressure continuously falls \u2014 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.<\/p>\n
The entire 20-minute fill promise lives or dies on real, proven compressor performance, so factory acceptance testing \u2014 rated pressure, flow and shaft power demonstrated at the manufacturer’s own works \u2014 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.<\/p>\n
A separate instrumentation air system runs alongside the main station: two reciprocating, non-lubricated, oil-free, water-cooled compressors at \u226540 kg\/cm\u00b2(g) and \u2265150 CFM each, with their own driers, filters and storage \u2014 so the gauges and instruments keep reading precisely even when the main air farm is roaring down during a test.<\/p>\n
Not on the first start \u2014 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.<\/p>\n
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?<\/strong>
\nBecause 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.<\/p>\n