20-Kw nitrogen diluent chemical oxygen-iodine laser

Abstract

A new Chemical Oxygen-Iodine Laser (COIL) has been developed and demonstrated at chlorine flow rates up to 1 gmol/s. The laser employs a cross flow jet oxygen generator operating with no diluent. The generator product flow enters the laser cavity at Mach 1 and is accelerated by mixing with 5 gmol/s, Mach 5 nitrogen diluent in an ejector nozzle array. The nitrogen also serves as the carrier for iodine. Vortex mixing is achieved through the use of mixing tabs at the nitrogen nozzle exit. Mixing approach design and analysis, including CFD analysis, led to the preferred nozzle configuration. The selected mixing enhancement design was tested in cold flow and the results are in good agreement with the CFD predictions. Good mixing was achieved within the desired cavity flow length of 20 cm and pressure recovery above 90 Torr was measured at the cavity exit. Finally, the design was incorporated into the laser and power extraction as high as 20 kw was measured at the best operating condition of 0.9 gmol/s. Stable resonator mode footprints showed desirable intensity profiles, with none of the sugar scoop profiles characteristic of the conventional COIL designs.

Development of efficient nitrogen diluted discharge-driven HF CW chemical laser

“…Discharge-driven chemical laser (DCL) typically employ low pressure dc, rf or microwave induced cold plasma to dissociate Fluorine contained molecules (Such as NF 3 ,SF 6 , and F 2 ), due to its low pressure, and temperature characteristics, it could directly reacted with injected H 2 /D 2 without further gas dynamic cooling and allow long time running. Due to high voltage dc discharge plasma's simpleness and easy to inject large amount of electric power, it was mostly used compared to rf and microwave discharge.…”

“…Since the high voltage dc-discharge is cold plasma, its plenum temperature is much lower than arc or combustion driven device, cryogenic adsorption, which had been successful applied to COIL [6], provides a possible way to reduce its size. However, it request ordinary used Helium dilute be replaced by Nitrogen at first, which had been wide known will greatly reduce chemical laser's efficiency since the early years of chemical laser development [7], and the decrease was significant on straight channel transverse injecting DCL [9] [10].…”

Singlet oxygen generators - the heart of chemical oxygen iodine lasers: past, present, and future

“…Researchers from the United States [32,33], Russia [31,34,35], the Czech Republic [22,36], China [37], India [38,39], Korea [40], Japan [41][42][43] and Israel [44,45] have built jet generators which can be classified by the direction of the chlorine and BHP flows; co-flow, counter-flow and cross-flow. The cross-flow variant has become the dominant type of jet generator.…”

Properties of O2(Δ1)–I(P21/2) laser medium with a dc glow discharge iodine atom generator

“…[9][10][11][12] Higher gas temperature is undesirable because the laser efficiency decreases as the temperature of the laser medium is increased. Therefore, at the iodine generator outlet, the total gas pressure should exceed 20 Torr, the iodine atom number density should be of the order of 10 16 cm −3 , and the gas temperature should be lower then 350 K. For higher pressure iodine flows, more efficient mixing schemes may be implemented.…”