One of the key factors ensuring gas turbine engines (GTE) competitiveness is improvement of life, reliability and fuel efficiency. However fuel efficiency improvement and the required increase of turbine inlet gas temperature (T*g) can result in gas turbine engine life reduction because of hot path components structural properties deterioration. Considering circumferential nonuniformity, local gas temperature T*g can reach 2500 K. Under these conditions the largest attention at designing is paid to reliable cooling of turbine vanes and blades. At present in design practice and scientific publications comparatively little attention is paid to detailed study of turbine split rings thermal condition. At the same time the experience of modern GTE operation shows high possibility of defects occurrence in turbine 1st stage split ring. This work objective is to perform conjugate numerical simulation (gas dynamics + heat transfer) of thermal condition for the turbine 1st stage split ring in a modern GTE. This research main task is to determine the split ring thermal condition by defining the conjugate gas dynamics and heat transfer result in ANSYS CFX 13.0 package. The research subject is the turbine 1st stage split ring. The split ring was simulated together with the cavity of cooling air supply from vanes through the case. Besides turbine 1st stage vanes and blades have been simulated. Patterns of total temperature (T*Max = 2000 °C) and pressure and turbulence level at vanes inlet (19.2 %) have been defined based on results of calculating the 1st stage vanes together with the combustor. The obtained results of numerical simulation are well coherent with various experimental studies (measurements of static pressure and temperature in supply cavity, metallography). Based on the obtained performance of the split ring cooling system and its thermal condition, the split ring design has been considerably modified (one supply cavity has been split into separate cavities, the number and arrangement of perforation holes have been changed etc.). All these made it possible to reduce considerably (by 40…50 °C) the split ring temperature comparing with the initial design. The design practice has been added with the methods which make it possible to define thermal condition of GTE turbine components by conjugating gas dynamics and heat transfer problems and this fact will allow to improve the designing level substantially and to consider the influence of different factors on aerodynamics and thermal state of turbine components in an integrated programming and computing suite.

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The purpose of this work is to realize the adaptive and productive potential of pigs with immunoprophylaxis of transport stress. Analysis of the morbidity and preservation of young pigs for the periods of growth and fattening found that immunotropic preparations PigStim-C and PigStim-M reduce morbidity, reduce recovery time and increase the effectiveness of therapeutic measures. Against the background of immunoprophylaxis, the incidence of pigs during the growth and fattening periods decreased by 4-5 %, the recovery time was reduced by 0.9-1.7 days, and the safety of pigs increased to 99 %, at 97 % in the control group. A more pronounced positive effect of the application of PigStim-C to diseases characterized by respiratory damage was revealed, and PigStim-M – the gastrointestinal tract. Prevention of transport stress by immunotropic preparations PigStim-C and PigStim-M contributed to an increase in live weight of pigs at the end of the growth period by 1.61 and 1.23 kg, respectively, more than control values, and by the end of the fattening period by 2.55 and 3.17 kg. A similar pattern was revealed in the dynamics of average daily increases in live mass. The average daily increases in the live weight of piglets against the background of the use of preparations of the PigStim series during the growth period were higher by 24.6-32.3 g, during the fattening period by 9.4-19.4 g, and on average for the growth and fattening periods by 17.0-21.2 g.

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