Перспективы применения в регенераторах ГТУ поверхностей теплообмена с интенсификацией теплоотдачи выступами и впадинами

Abstract

Определено влияние размещения на наружной и внутренней поверхностях трубок впадин и выступов различной формы на теплоотдачу, гидравлическое сопротивление и массу трубчатого регенератора ГТУ. Установлено, что перспективным является применение тонкостенных (толщина стенки 1 мм) трубок с лунками на наружной поверхности, которые увеличивают теплоотдачу в 1,16 – 1,97 раза при незначительном увеличении сопротивления, что приведет к снижению массы поверхности теплообмена до 33 %.

The heat regeneration results in an increase in the efficiency factor of gas turbine plant (GTP) on average by 6 to 8% (absolute); however the plant size and mass are increased significantly. In this connection, when designing the regeneration GTP an important task is to reduce the regenerator mass and increase its compactness; one of the ways to the solution of this problem is to make use of intensified heat-exchange surfaces. Joint experimental and computational research done by the Institute for Engineering Heat Physics of the National Academy of Sciences of Ukraine and the state-owned Scientific and Production Company SE Gas Turbine Scientific Production Complex "Zorya"-"Mashproekt" allowed us to determine the influence produced by the ridges and cavities of a different shape arranged on external and internal pipe surfaces on the heat release, hydraulic resistance and the tubular regenerator mass. It has been established that the arrangement of holes on the external surface would increase the heat release by a factor of 1.16 to 1.97 with an insignificant increase in the resistance (on average 1.01 times), which will result in the reduction of the mass of heat exchange surface by 33 %. Spiral grooves made on the external surface of the pipes would increase the heat release 1.5 – 1.9 times with the 21 to 32 % mass reduction. The formation of cylindrical projections on the internal surface of pipes would increase the heat release 1.03 – 1.5 times and the resistance 1.18 – 2.85 times which may result both in the mass decrease (by 18 %) and the mass increase (by 27 %). The use of spiral ribs results in 1.75 – 2.25 times increase in the heat release and 4.05 – 6.8 times increase in the resistance and the mass is increased by 37 %.