FIRST STEPS TOWARD SPACE - Smithsonian Institution Libraries

17
First Rocket and Aircraft Flight Tests of Ramjets
Introduction
The development of space rockets presents a
rather complex scientific problem. Among all the
problems which affect the successful development
of space technology that of rocket power engineering
is the most important one. We may confidently
say that the launching of Earth satellites, rocket
flights to the Moon, Venus, and Mars, manned
orbital flights, and soft landing on the Moon are
the significant steps in the development of the
Soviet space technology. Therefore it is quite clear
that the creation and improvement of rocket engines
and the choice of the most efficient propellants
for them will remain one of the key and governing
problems in modern space technology for many
decades to come, just as at the dawn of the space
age.
The first to advance and substantiate the idea of
applying engines using atmospheric oxygen for
boosting space vehicles during their motion in the
atmosphere was Konstantin Eduardovich Tsiolkovskiy.
1
Fridrikh Arturovich Tsander and other investigators
made a great contribution to the study of
this problem. 2
At present the idea of using ramjet engines for
boosting space rockets is generally recognized. Numerous
theoretical and experimental investigations
published in the world press show that the use of
ramjet engines in the first stages of carrier-rockets
will allow a severalfold increase in the mass of a
satellite put into orbit, with the rocket launching
weight being unchanged.
Academician Boris Sergeyevich Stechkin, one of
the closest pupils and followers of N.E. Zhukovski,
delivering lectures on hydrodynamics at the Me­
Yu. A. POBEDONOSTSEV, Soviet Union
177
chanics Department of the Moscow N.E. Bauman
Higher Technical School in 1923, set forth a new
theory of a ramjet engine. Strictly following the
classic gas-dynamics laws, he derived for the most
general case equations for the thrust and efficiency
of a ramjet engine operating in an elastic medium.
For an incompressible fluid, without thermal effects
being considered, the problem of a reaction
force of a fluid jet through a jet engine was developed
in detail earlier by N.Ye. Zhukovskiy and
presented in his classical works: "On Reaction of
Fluid Inflow and Outflow" and "Contribution To
the Theory of Ships Propelled by the Reactive
Flow of Water."
The analogous investigation of the compressible
flow was carried out for the first time by B.S.
Stechkin. He detailed the problem of energy input
to the air jet inside the ramjet; and he concluded
that the law of heat transfer to the air can be arbitrary,
but the integral defining the operation must
be taken in a closed loop (in the coordinates pv)
presenting the process of changing the state of the
air passing through the ramjet. Thus, the thermal
efficiency of the heating cycle of the air in a ramjet
was immediately determined. The total efficiency of
a ramjet was defined as the product of the thermodynamic
efficiency and the propulsion-unit efficiency,
or, as it is now called, "the efficiency of
motion" or "propulsive efficiency."
In addition, he showed how to define the efficiency
of a ramjet engine when the air gets energy
partly or wholly from the outside, and considered
the case of air-jet compression at the expense of a
free stream impulse loss, as it was proposed by Rene
Lorin. 5 In this case the air passes on the Brayton
cycle and its thermal efficiency will equal the diference
between unity and the ratio of the air tem-