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Shock drag and aeroheating are major problems faced by hypersonic vehicles. This study proposes a novel three-dimensional model combining spike-aerodisk with a bleed air channel featuring multiple lateral nozzles for drag and aeroheating reduction. The high-temperature and high-pressure air at the stagnation point of the aerodisk is introduced into the channel and ejected laterally through multiple nozzles to modify the flow field structure and reduce drag and aeroheating. In contrast to previous research employing a two-dimensional axisymmetric assumption, our innovation considers the structure of the exit nozzles and the spacing between nozzles. Due to multiple lateral nozzles, the connection thickness between nozzles can lead to asymmetric flow phenomena. Three-dimensional flow field simulation has been employed with the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the shear stress transport (SST) k-ω turbulence model. The effects of the convergence half-angle of the channel inlet, the divergent angle of the nozzle, and the nozzle position on modifying the characteristics of the flow field are studied. Increasing the convergence half-angle of the channel inlet can further push away the reattachment shock, but when it exceeds 60°, the drag reduction performance degrades. Reducing the divergent angle of the nozzle and increasing the number of nozzles can reduce the drag coefficient and the peak value of the Stanton number. However, when the divergent angle is reduced to 10°, the performance of reducing drag and aeroheating is weakened. In the range of research parameters, when the convergence half-angle is 60°, the divergent angle is 15°, and the nozzles are located in the middle of the spike, compared with the plain spike-aerodisk model, the drag coefficient and peak Stanton number of the combined model are further reduced by 17.8 % and 34.8 %, respectively. Our findings confirm that a multi-nozzle can effectively reduce drag and aeroheating while the channel structure is viable in practice. • A new model of lateral jet without gas source is studied by 3-D numerical simulation. • The gas for the lateral jet is coupled with the outside flow. • A distribution form of multiple lateral nozzles is proposed. • A realistic 3-D simulation is conducted, enhancing its practical applicability. [ABSTRACT FROM AUTHOR]

By slotting an inlet at the head of the aerodisk, a channel through the spike, and the lateral jet outlet at the middle of the spike, the blunt body with spike-aerodisk can further reduce its aeroheating and drag. In this paper, the numerical simulation method was used to analyze the flow field structure of this spike-aerodisk-channel, the effects of the spike length, the aerodisk diameter, and the channel diameter on the drag and aeroheating performance of this spike-aerodisk-channel configuration were studied. In general, the lateral jet introduced by the channel from the stagnation region of the aerodisk leads to the shear layer separation in advance, pushes the separation shock away from the spike, enlarges the recirculation zone near the blunt body, avoids the interaction between the separation shock and the reattachment shock, increases the distance from the reattachment shock to the surface of the blunt body. The reattachment shock strength of the blunt body is weakened. With increased spike length and channel diameter, drag and aeroheating reduction are improved. With the increase of the diameter of the aerodisk, the aeroheating performance is improved, but the drag reduction performance continues to decline. Compared with the plain spike-aerodisk, the spike-aerodisk-channel is generally conducive to further drag and aeroheating reduction. In the range of research parameters, considering the effect of drag and aeroheating reduction and the structural feasibility, the spike-aerodisk-channel has the best drag and aeroheating reduction performance when the spike length is twice the blunt-body diameter, the ratio of the aerodisk diameter to the blunt-body diameter is 0.3, and the ratio of the channel diameter to the blunt-body diameter is 0.075. Compared with the plain spike-aerodisk of the same size, the aeroheating reduction efficiency is increased by 37.9%, and the drag reduction efficiency is increased by 16.0%. • Drag and aeroheating reduction mechanism of the spike-aerodisk and channel concept under hypersonic conditions was investigated by the numerical simulation. • Three influence factors were analyzed and compared comprehensively. • Combined spike-aerodisk and channel concept is a promising drag and aeroheating reduction technique. [ABSTRACT FROM AUTHOR]