Fig.1

Tail-propelled UAV with turboprop engine

Fig.2

Inlet/volute configuration

Fig.3

Inlet/volute test model

Table 1

Inlet geometry parameters

Fig.4

Test system device diagram

Fig.5

Surface mesh of computational domain and inlet

Fig.6

Static pressure distribution for different meshes

Fig.7

Mach number distribution of AIP for different meshes

Fig.8

Comparison of static pressure distribution of inlet symmetrical surface between test and simulation

Fig.9

Schematic diagram of swirl angle

Table 2

Experimental and simulation results of inlet performance at different exit Mach numbers

Fig.10

Test and simulation total pressure recovery coefficient distribution of AIP

Fig.11

Swirl angle and secondary streamline distribution of AIP

Fig.12

Swirl angle distribution at different MaAIP

Fig.13

Distribution of SD at different MaAIP

Fig.14

Distribution of SP at different MaAIP

Fig.15

Wall friction line of inlet（MaAIP=0.264）

Fig.16

Total pressure and secondary streamline distribution of inlet section（MaAIP=0.264）

Fig.17

Static pressure and velocity vector distribution at inlet/volute interface （MaAIP=0.264）

Fig.18

Flow field and pressure distribution on symmetry plane at different MaAIP

Fig.19

Intensity of secondary flow on upper section of volute

Fig.20

Mach number distribution of different sections

Fig.21

Static pressure and total pressure distribution of section A （lift） and section B （right）

Fig.22

Vortex structure shown by Q criterion （Q′=1×10-5）

Fig.23

Pressure and spatial streamline distribution of inlet （MaAIP=0.376）

Fig.24

Swirl angle distribution of bend/straight inlet（MaAIP=0.376）

Fig.25

Comparison of bend/straight swirl intensity SI

Fig.26

Comparison of bend/straight ηα15