Thermal analysis of COIL

Comparison Study of Subsonic and Transonic Mixing in a Multi-Kw Grid-Nozzle Supersonic Chemical Oxygen Iodine Laser

“…For the subsonic injection, we omitted the data for the downstream half of the laser cavity due to large measurement error. As predicted by thermal analysis, 7) the gas medium for subsonic injection has a higher heat release and a higher temperature than that for transonic injection. In both schemes, increasing the iodine flow rate results in an increase in temperature.…”

“…( 3) represent the heat per unit of time released from the gas mixture, and the terms on the right-hand are defined as follows: q Á n I 2 FN is the energy released from O 2 ( 1 Á) during the iodine dissociation, q I 2 n I 2 F is the energy consumed by molecular iodine for the dissociation, and q I Ã n I 2 F Á 2K e Y= fðK e À 1ÞY þ 1g is the energy consumed by atomic iodine for the excitation. The stagnation temperature of the primary flow T 0ip was determined by gasdynamic method 7) from the experiments without secondary flow and was found to be approximately 300 K. For the secondary flow, T 0is was close to the temperature of the iodine supplying duct, because the gas traveled inside the duct at low subsonic speed. The pipes were preheated up to 100 C in order to avoid iodine condensation, so T 0is was taken as 373 K. The last unknown parameter is the stagnation temperature in the laser cavity T 0 .…”

“…The cavity temperature calculated while the pressure broadening taking into account is in agreement with the data obtained by the gasdynamic model. 7)…”

“…Experimental measurement of temperature made it possible to check the accuracy of the heat release evaluation performed. 7) The results of temperature measurement for subsonic and transonic injections are shown in Figs. 4 and 5, respectively.…”

“…As the static pressure inside the cavity changes along the flow, we can estimate T 0 only at the point 7 cm downstream from the NEP, where the pressure gage is installed. This estimation was performed using the model described in our paper, 7) and the values of T 0 are listed in the Table III, which lists the results for eqs. ( 1)-( 3).…”