They were the first to send instruments into space. The Soviets were the first to orbit the Earth. The Bay of Pigs incident was internationally embarrassing. Kennedy was a symbol of a new era, a man who could move the country forward after years of stagnation.īut by May 1961 the gloss had started to wear off his presidency. The man he succeeded, Eisenhower, was at that time the oldest president. After all, he was young, he was charismatic and he had an optimistic vision on his side. He started his term in January 1961 with a confidence that he would head an administration which would achieve great things, both domestically and in foreign affairs. election he was the youngest person to be elected President. President John F Kennedy, address to Congress on No single space project in this period will be more impressive to mankind, or more important in the long-range exploration of space and none will be so difficult or expensive to accomplish. For example, the numerous tests required to develop rocket engines are largely in part due to the need to eliminate or reduce the impact of thermoacoustic combustion instabilities.I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth. This process identifies a combustion-instability region and attempts to either eliminate this region or moved the operating region away from it.
Moreover, flame blowoff of an aero-gas-turbine engine in mid-flight is clearly dangerous (see flameout).īecause of these hazards, the engineering design process of engines involves the determination of a stability map (see figure). For instance, thermoacoustic instabilities are a major hazard to gas turbines and rocket engines.
In many practical cases, the appearance of combustion instabilities is undesirable. This combustor operates at conditions in which no dangerous combustion-instabilities will happen. Stability map of a hypothetical combustor.
Combustion instabilities are physical phenomena occurring in a reacting flow (e.g., a flame) in which some perturbations, even very small ones, grow and then become large enough to alter the features of the flow in some particular way.
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