Vertical Take-off and Landing of Hybrid Rocket Motor Powered Platform
Date11th Jan 2023
Time03:00 PM
Venue Google Meet
PAST EVENT
Details
Aircraft with Vertical Takeoff and Landing (VTOL) capability does not require long and well-paved runways, thus enabling faster point-to-point transport. Since the first powered flight in 1903, there have been many conceptual designs and prototypes for VTOL aircraft, of which only a few made it to the operational phase. One of the fundamental difficulties faced in the development of fixed-wing VTOL aircraft is the significant mismatch in the thrust requirement for cruise and hover (VTOL). The need for a higher thrust during hover leads to increased engine size, which acts as a dead weight and causes additional drag during the cruise. To comply with the thrust requirements for the take-off and landing flight leg of a VTOL system, a mechanism that produces high thrust for a short duration (like rocket thrusters) would suffice. In this work, the use of a hybrid rocket thruster is proposed to augment the thrust during vertical takeoff and landing. Classical hybrid rocket motors -- having solid fuels and gaseous/liquid oxidisers -- are controllable although the precise thrust control of these hybrid motors is still being researched. To study the suitability of using a hybrid rocket for augmenting the VTOL capability, a lab-scale hybrid motor with wax-aluminium-based solid fuel with air as the oxidiser was developed. Closed-loop thrust control of this hybrid rocket motor was achieved in this study to establish the thrust control capabilities of the proposed hybrid rocket motor. The control algorithm utilised a PID controller with chamber pressure feedback. Numerical simulations and cold flow tests were carried out to identify the suitable gains for the PID control algorithm. The resultant closed-loop system followed the reference pressure within 1.86% for a reference pressure of 4.69 bar during the step input response test of the system. The response of the system for a ramp input, with linear thrust variation from 78.4 N to 127.4 N in eight seconds, showed that the measured thrust followed the desired ramp profile with a root-mean-square error of 1.99 N. To study the use of a hybrid rocket motor in the afterburner section of a gas turbine engine towards augmenting the thrust during takeoff and landing, an off-the-shelf micro gas turbine engine was used. The engine was characterised and a platform with four gas turbine engines was designed and developed to study the attitude stabilisation for the VTOL platform. To evaluate the feasibility of a smooth landing, numerical simulations are being carried out to analyse and select a suitable velocity-tracking algorithm for landing. After identifying the algorithm, a hardware-in-loop simulation is proposed for validating the algorithm with the developed hybrid rocket motor in the loop.
Speakers
Mr. Anandu Bhadran, AE17D750
Department of Aerospace Engineering