Experimental and Numerical Investigation of Convective Heat Transfer in a Gas Turbine Can Combustor

Abstract

Experiments and numerical computations are performed to investigate the convective heat transfer characteristics of a gas turbine can combustor under cold flow conditions in a Reynolds number range between 50,000 and 500,000 with a characteristic swirl number of 0.7. It is observed that the flow field in the combustor is characterized by an expanding swirling flow, which impinges on the liner wall close to the inlet of the combustor. The impinging shear layer is responsible for the peak location of heat transfer augmentation. It is observed that as Reynolds number increases from 50,000 to 500,000, the peak heat transfer augmentation ratio (compared with fully developed pipe flow) reduces from 10.5 to 2.75. This is attributed to the reduction in normalized turbulent kinetic energy in the impinging shear layer, which is strongly dependent on the swirl number that remains constant at 0.7 with Reynolds number. Additionally, the peak location does not change with Reynolds number since the flow structure in the combustor is also a function of the swirl number. The size of the corner recirculation zone near the combustor liner remains the same for all Reynolds numbers and hence the location of shear layer impingement and peak augmentation does not change.

Impact of Swirl Flow on the Cooling Performance of an Effusion Cooled Combustor Liner

“…Hence, the distributions found are unique for single geometry combinations of airspray nozzle and heat shield design and independent from the airspray nozzle operating conditions. This result is also confirmed by the studies conducted by Patil et al [13]. Figure 3 shows a contour plot for test case C3 and C4.…”

“…Basic considerations on the effect of various Reynolds numbers on the convective heat transfer in a gas turbine can combuster has been conducted by Patil et al [13]. In this study, an airspray nozzle is investigated at a swirl number of 0.7.…”

Modelling of heat transfer and fluid flow in the hot section of gas turbines used in power generation: A comprehensive survey

“…A model with a side wall was used to study the sharp edge case under slip and nonslip boundary conditions. Moreover, slip boundary conditions with side walls were used for the radiused edge case to conserve the computation time …”

Effect of thermal stress on creep lifetime for a gas turbine combustion liner

“…Since the thermal stress is mainly induced by the temperature differences along the substrate which leads to the critical thermal damage of the hot components, there is a critical requirement to predict the thermal stress distributions of hot components under an actual operating condition [10][11][12] Under this circumstance, most of the studies on the gas turbine hot components are mainly focused on fluid dynamics or heat transfer measurement/enhancement. Likewise, for the combustion systems, there are also numerous studies such as combustion mechanism, combustion gas flow, and heat transfer in combustors [13][14][15]. There have been some efforts to predict failure and lifetime in combustors, but only for the local part of component or segments in archival journal papers [16,17].…”