This experimental investigation focused on the ignition and combustion characteristics of a tandem cavity-based scramjet combustor with side-by-side identical cavities. study utilized Pusan National University-direct connect (PNU-DCSC), which was capable simulating flight conditions at Mach number 4.0–5.0 altitudes 20–25 km using vitiated air heater (VAH). The tests were conducted under off-des...

Title of Document: SPRAY FLAME AND EXHAUST JET CHARACTERISTICS OF A PRESSURIZED SWIRL COMBUSTOR Martin Brendan Linck, Doctor of Philosophy, 2006 Directed By: Professor Ashwani K. Gupta Department of Mechanical Engineering This work describes an investigation of swirl-stabilized flames, created in a combustor featuring co-annular swirling airflows, under unenclosed, enclosed, and submerged condi...

Since its founding, NASA has been dedicated to the advancement of aeronautics and space science. The NASA Scientific and Technical Information (STI) Program Office plays a key part in helping NASA maintain this important role. The NASA STI Program Office is operated by Langley Research Center, the Lead Center for NASA's scientific and technical information. The NASA STI Program Office provides ...

Gas turbines are being utilized in a variety of applications (electric power production, jet engines, etc.) Modern power turbines have the highest operating efficiencies and turn out the fewest pollutants among major combustion energy converting devices. The power generation industry is faced with increasingly stringent emissions requirements for ozone precursors, such as nitrogen oxides and ca...

Increasing the combustion temperatures in a gas turbine engine to achieve higher efficiency and power output also results in high heat loads to turbine components downstream of the combustor. The challenge of adequately cooling the nozzle guide vane directly downstream of the combustor is compounded by a complex vortical secondary flow at the junction of the endwall and the airfoil. This flow t...

The high performance and instability in combustion chamber are the most challenging requirements for faster developments and technical advances in most of the engines. The design and development challenges of such engines are highly influenced by its combustion behavior taking place inside the combustion chamber. Studies on the injection, vaporization and combustion phenomena inside combustion ...

High-bandwidth fuel modulation is currently one of the most promising methods for active combustion control. To attenuate the large pressure oscillations in the combustion chamber, the fuel is pulsed so that the heat release rate fluctuations damp the pressure oscillations in the combustor. This thesis focuses on the development and implementation of a high-bandwidth, proportional modulation sy...

In this paper, the effect of adding hydrogen to the composition of methane and air in a micro combustor is investigated by a three-dimensional numerical method. First, the results of the current study in determining the wall temperature of the micro combustion chamber are compared with those obtained from the experimental and numerical results of the previous research. By confirming the numeric...

An efficient finite volume approach has been used to develop a three dimensional Helmholtz acoustic solver for complex geometries. This acoustic solver was utilized to obtain characteristic mode shapes and frequencies of a baffled combustion chamber. An experimental setup, including stationary and moving sensors, has also been used to measure these quantities for the same model combustion chamb...

This report describes sensing strategies that were developed for monitoring the health and performance of gas turbine combustors. Sensor systems based on these approaches enable control and monitoring systems that improve combustor reliability and operability, achieve optimal performance (e.g., lower NOx emissions) over extended periods of time, reduce maintenance, prevent forced outages, and i...