Forebody shock control devices for drag and aero-heating reduction: A comprehensive survey with a practical perspective

Abstract

One key feature that distinguishes the flowfield around vehicles flying in supersonic and hypersonic regimes is the bow shock wave ahead of forebody. The severe drag and aeroheating impacting these vehicles can be significantly reduced if the bow shock wave ahead of the vehicles forebodies is controlled to yield weaker system of oblique shocks. Benefits of forebody shock control include increasing flight ranges, economizing fuel consumption, reducing dead weights, and thermally protecting forebody structure and onboard equipment. Forebody shock control that has been widely studied since the early 1900s is achievable in numerous techniques that vary according to the mechanism of control. While some of these techniques have already been implemented in real systems, other techniques involve serious complications and tough trade-offs. The present paper is intended to serve as the first comprehensive survey on the field of forebody shock control devices. The objectives of the present paper are multifold. The paper categorizes the various forebody shock control devices in a physics-based manner, explains the underlying physics for each device, and surveys the key studies and state-of-the-art knowledge. The paper also addresses the existing gaps in knowledge, highlights the existing systems implementing these devices, and discusses the associated practical implementation issues and design-tradeoffs. 2. Structural devices, the mechanical spikes: 2.1. Principle of operation of mechanical spikes Drag and Aeroheating Reduction Devices Fluidic Devices Opposing jets Structural Devices Mechanical spikes Energetic Devices Energy deposition Basic devices Structural-Fluidic Devices Structural-Energetic Devices Hybrid devices

Dynamics of Shock Structure and Frontal Drag Force in a Supersonic Flow Past a Blunt Cone under the Action of Plasma Formation

“…Control of supersonic flows by means of plasma formations generated by electrical discharges, microwave energy release, and laser pulses is currently an extensive field of aerospace engineering studies (see [1] and surveys in [2][3][4][5][6]). A review of various applications of theoretical and experimental studies for supersonic and hypersonic flow modes in order to control drag reduction, establish the effective geometry of the vehicle, and mitigate sonic boom from it was presented in [7].…”

Numerical Simulation of Supersonic Carman Curve Bodies with Aerospike

“…Among these techniques, attaching an aerospike at the top of the supersonic vehicle proved to be an efficient and simple way to accomplish a significant reduction in drag and aerodynamic heating [4]. And the aerospikes are the sole drag and aeroheating device that has been successfully implemented in real systems (see Figure 1), and other devices were not used in any real system [5].…”

Mach Number Dependence of Flow Instability around a Spiked Body

“…The strength of shock wave governs the drag experienced by the object and producing of aerodynamic heating at high supersonic and hypersonic flows. The manipulation of this shock wave, aiming to control its strength was motivation of various flow control studies [1]. However, utilization of various flow control methods has not been realized or effectively utilized because of either unsteadiness associated with the control or complication of systems.…”

“…The flow control methods for shock manipulation can be classified into active and passive controls. The mechanical spike mounted in front of a blunt body, has been deemed beneficial as a passive flow control technique towards reducing the heat transfer and aerodynamic drag in supersonic and hypersonic flows [1]. The flow unsteadiness in the form of pulsation and oscillation associated with spike has been widely researched and studied in the past [2,3,4].…”