Design of a Three-Dimensional Hypersonic Inward-Turning Inlet with Tri-Ducts for Combined Cycle Engines

Abstract

The operation of a propulsion system in terms of horizontal takeoff/landing and full-speed range serves as one of the main difficulties for hypersonic travelling. In the present work, a three-dimensional inward-turning inlet with tri-ducts for combined cycle engines is designed for the operation of three different modes controlled by a single rotational flap on the compression side, which efficiently simplifies the inlet structure and the flap control mechanism. At high flight speed between Mach 4 and 6, the pure scramjet mode is switched on, whereas both the ejector and the scramjet paths are open for a moderate Mach number between 2 and 4 with a larger throat area guaranteeing the inlet startability. In the low flight speed range with Mach number below 2, the additional turbojet path will be turned on to supply air for the turbine engine, whereas the other two paths remain open for spillage. Numerical simulations under different operation modes have proven the feasibility and good performance of the designed inlet, e.g., a nearly full mass flow ratio and a total pressure recovery around 0.5 can be achieved at the cruise speed. Meanwhile, the inlet works properly at low flight speeds which overcomes the typical starting problem of similar inlet designs. In the near future, wind tunnel experiments will be carried out to validate our inlet design and its performance.

Flow Field Reconstruction of 2D Hypersonic Inlets Based on a Variational Autoencoder

“…Although the Mach numbers are different, the results may still be reliable enough, as done in Ref. [27]. Figure 8 shows the flow field of sample ID-001.…”

Machine Learning-Based Backpressure Unstart Prediction and Warning Method for Combined Cycle Engine Hypersonic Inlet-Oriented Wide Speed Range

“…Combined Inlet Model. The three-dimensional inwardturning multiducted combined inlet was proposed by Zhu et al [37,38]. Cai et al [39] confirmed that its geometric aerodynamic characteristics can meet the requirements of the propulsion system, which is capable of continuous oper-ation in a wide speed range.…”

Analysis on the Low Speed Performance of an Inward-Turning Multiduct Inlet for Turbine-Based Combined Cycle Engines

“…A three-dimensional inwardturning tetraduct inlet for turbine-based combined cycle engines has been designed in the present paper based on the methodology proposed in Ref. [12]. But different from the previous upper arrangement of a single duct for the turbine engine (referred to as T-duct hereafter) in Ref.…”

“…But different from the previous upper arrangement of a single duct for the turbine engine (referred to as T-duct hereafter) in Ref. [12], two T-ducts are adopted in this work in order to meet the mass requirement of the combined cycle engine. The configuration of the tetraduct inlet is shown in Figure 1, where the two side ducts denoted by T are the flow paths for the turbine engine, the upper duct corresponds to the flow path for the ejector-ramjet engine (referred to as E-duct hereafter), and the lower duct is the flow path for the scramjet engine (referred to as S-duct hereafter).…”