ADVANCED PROPULSION SYSTEMS (APSYS) LAB
High Speed Propulsion Lab in IIT Kharagpur, India
ABOUT
The APSYS lab is located at 001 ground floor of Annex Building in the Aerospace Engineering Department, IIT Kharagpur, India. Research on high speed propulsion, pulse jet ignition, vortex combustion, thermoacoustics, spark ignition, jet deflection, etc is being conducted experimentally and computationally. The group performs flow imaging, flow diagnostics, pressure measurements on scaled down test objects. Members have access to a super-computing facility for running computer codes like Fluent, SU2, OpenFoam etc. The Lab has a dedicated compressed air facility, a direct connect modular flow facility capable of running various aerothermodynamic studies. A team of PhD students, MTech students and Undergrad students work on various projects.
NEWS AND ANNOUNCEMENTS
APSYS Labs receives DST funding for turbulent combustion research. The funding will cover equipment procurement for pressure measurements and the purchase of specialty gases used in the tests.
General Information
Areas of research include combustion oscillations, vortex driven flows, pulsating flows, method of characteristics, combustion sciences etc.As part of our work in high speed combustors, we are studying flame behavior, ignition, stabilization, flashback and mode transition in high speed combustors both with cavity assisted and strut assisted flame stabilization mechanisms. As part of our work on Combustion Instability prediction and control, we are also looking at vortex driven resonant combustion in Gas Turbine combustors. Active combustion control using secondary injection targeting q' oscillation tailoring are being attempted.
PEOPLE
Instructors, Students, Collaborators, RAs, TAs etc.
Current Members
Past Members
POSTS FROM THIS GROUP
Posts about publications, achievement, facilites, books from this group
Vortex Driven Heat Release Modulation Premixed Combustors
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
The study demonstrates that the dump plane is not merely a geometric boundary but can actively trigger and amplify thermoacoustic oscillations through near-field counter-rotating vortex interactions. Under certain forcing conditions, this creates rapid heat release events synchronized with pressure oscillations, leading to strong positive feedback and instability growth. The paper extends previous work on vortex–wall and vortex–nozzle interactions by identifying the dump plane itself as an ac...
Read more
Gaps in Understanding Combustion Dynamics of Scramjet Engines
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
https://doi.org/10.1016/j.ast.2025.111046 Scramjet combustion dynamics remain among the most complex and least understood areas in high-speed airbreathing...
Read more
TBCC RBCC Mode switch challenges
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
TBCC vs RBCC Transition Challenges TBCC (Turbine-Based Combined Cycle) — Compressor-Side Issues 1. Primary operability risk: compressor surge, stall, blade choking as inlet total temperature and pressure ratio rise; downstream back-pressure transients...
Read more
A Matlab code of how to do dynamic mode decomposition of a video sequence.
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
A Matlab code of how to do dynamic mode decomposition of a video sequence. (ChatGPT) % DMD on a Video Sequenceclear; close all; clc; %% Load VideovideoFile = 'video.mp4'; % Change to your video filev = VideoReader(videoFile); % ParametersresizeFactor = 0.25; % Reduce size to speed upnumFrames = min(100, floor(v.Duration * v.FrameRate)); % Limit number of frames % Read and preprocess video framesX = [];...
Read more
Bychkov Limit (ChatGPT, Google AI)
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
The Bychkov limit, also known as the detonation cell size limit, is a concept in detonation physics that describes the minimum size of a detonation...
Read more
Independent Component Analysis (ICA) for a video sequence. ChatGPT
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
%Here's a MATLAB code that performs Independent Component Analysis (ICA) on a video sequence. The goal is to treat each frame as a data %vector and then extract statistically independent components from this set using ICA. %This is particularly useful for motion segmentation...
Read more
Principle Component Analysis (PCA) Matlab Code (ChatGPT)
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
% PCA on an image setclc; clear; close all; % Set image directoryimageDir = 'images/'; % Change this to your image folder pathimageFiles = dir(fullfile(imageDir, '*.png')); % Change extension if needed (e.g., .jpg, .bmp)numImages = length(imageFiles); % Read first image to get dimensionsfirstImage = imread(fullfile(imageDir, imageFiles(1).name));if size(firstImage, 3) == 3firstImage = rgb...
Read more
Wavelets in Signal Processing
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
Above Image is from Arts, L.P.A., van den Broek, E.L. The fast continuous wavelet transformation (fCWT) for real-time, high-quality, noise-resistant time–frequency analysis. Nat Comput Sci 2, 47–58 (2022). https://doi.org/10.1038/s43588-021-00183-z How does wavelet transform differ from spectrogram when used on the same time series data ? ChatGPT : Both wavelet transform and spectrograms are time-frequency analysis tools, but the...
Read more
Insights into flame flashback phenomenon utilizing a Strut-Cavity flame holder inside scramjet combustor
Pranay Singeetham #Advanced Propulsion Systems (APSYS) Lab @Amardip Ghosh
Understanding upstream flame propagation in scramjets is challenging, particularly concerning flame flashback in a combustor with a novel strut-cavity flame holder. Two-dimensional unsteady Reynolds-averaged Navier–Stokes (URANS) simulations were performed to investigate how Mach number and wall divergence affect flame behavior. The utility of the strut-cavity flame holder was highlighted through a study of its non-reacting flow characteristics. Flow dynamics are significantly altered as the...
Read more
SCRAMJET Test Rig Instrumentation
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
The rig is being instrumentated for transitioning from cold flow supersonic mixing studies to reacting flow mode transition studies.
...Read more
Attachments
| 1. Minwook Chan PhD Thesis | |
| 2. PhD Thesis |
Understanding upstream flame propagation in scramjets is challenging, particularly concerning flame flashback in a combustor with a novel strut-cavity flame holder. Two-dimensional unsteady Reynolds-averaged Navier–Stokes (URANS) simulations were performed to investigate how Mach number and wall divergence affect flame behavior. The utility of the strut-cavity flame holder was highlighted through a study of its non-reacting flow characteristics. Flow dynamics are significantly altered as the shear layer above the cavity interacts with the downstream hydrogen jet. Shear layer dynamics and fuel-air mixing are improved through key factors such as shock-train behavior, cavity oscillations, and transverse fuel injection. The submerged fuel jet is less exposed to supersonic flow and demonstrates reduced entropy rise, achieving a 16% increase in mixing efficiency compared to standalone struts and a 46% improvement over transverse injection without a flame holder. Thermal choking shifts the shock train upstream, facilitating interactions with the shear layer and enhancing vortex formation, which decreases flow speed and promotes upstream flame propagation. The presence of OH radicals indicates that flame flashback follows a periodic pattern with an initial gradual slope, suggesting effective anchoring. Stability and flashback likelihood are affected by low-speed zones, vortex merging, and wall divergence. At Mach 3, combustion efficiency improves without wall divergence due to...
https://doi.org/10.1016/j.ast.2025.111046
Scramjet combustion dynamics remain among the most complex and least understood areas in high-speed airbreathing propulsion. Despite decades of research, important knowledge gaps persist, especially in the context of mode transitions between ramjet and scramjet operation, the unsteady response of pseudo-shocks to sudden changes in combustor heat release, and the mechanisms responsible for self-sustained oscillations that arise due to injector–flame–acoustic coupling. These gaps are particularly significant for both strut-stabilized and cavity-stabilized combustors, which exhibit fundamentally different dynamic behaviors.
A major limitation in current understanding lies in the characterization of SCRAM-to-RAM mode transitions. Most existing studies focus on steady-state conditions, while the actual transition process—marked by hysteresis, metastable modes, and complex transient phenomena—remains poorly documented, especially under flight-relevant enthalpy levels. Quantitative criteria for predicting mode transitions are still geometry-specific and do not consistently account for...
Gaps in Understanding Combustion Dynamics of Scramjet Engines
BROWSE POSTS
Find content on publications, achievement, facilites etc
RECENT POSTS
Posts arranged recent first
CONTACT Advanced Propulsion Systems (APSYS) Lab
Emails through this form are monitored for spam
8766 1 1 1
FEATURED POST
BTP and MTP Project Topics - 2023 Batch
Amardip Ghosh #Advanced Propulsion Systems (APSYS) Lab
This year we have a large number of BTP and MTP students as well as students from outside schools interning with our lab. While we remain open to project suggestions from students and sponsors, we also want to create a thematic focus of projects we want students to work on. If you have signed up with our lab for your BTP, MTP or Summer Internship, you can go over the list of topics we are proposing. Also read up the literature in the attachments section. You may be able to extend the work des...
Read more
Attachments