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A Caltech Library Repository Feedhttp://www.rssboard.org/rss-specificationpython-feedgenenFri, 12 Apr 2024 16:09:07 +0000The "limiting line" in mixed subsonic and supersonic flow of compressible fluids
https://resolver.caltech.edu/CaltechAUTHORS:20140805-134608325
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-Shen'}}]}
Year: 1944
It is well known that the vorticity for any fluid element is constant if the fluid is non-viscous and the change of state of the fluid is isentropic. When a solid body is placed in a uniform stream, the flow far ahead of the body is irrotational. Then if the flow is further assumed to be isentropic, the vorticity will be zero over the whole field of flow. In other words, the flow is irrotational. For such flow over a solid body, it is shown by Theodorsen that the solid body experiences no resistance. If the fluid has a small viscosity, its effect will be limited in the boundary layer over the solid body and the body will have a drag due to the skin friction. This type of essentially isentropic irrotational flow is generally observed for a streamlined body placed in a uniform stream, if the velocity of the stream is kept below the so-called "critical speed." At the critical speed or rather at a certain value of the ratio of the velocity of the undisturbed flow and the corresponding velocity of sound, shock waves appear. This phenomenon is called the "compressibility bubble." Along a shock wave, the change of state of the fluid is no longer isentropic, although still adiabatic. This results in an increase in entropy of the fluid and generally introduces vorticity in an originally irrotational flow. The increase in entropy of the fluid is, of course, the consequence of changing part of the mechanical energy into heat energy. In other words, the part of fluid affected by the shock wave has a reduced mechanical energy. Therefore, with the appearance of shock waves, the wake of the streamline body is very much widened, and the drag increases drastically. Furthermore, the accompanying change in the pressure distribution over the body changes the aerodynamic moment acting on it and in the case of an airfoil decreases the lift force. All these consequences of the breakdown of isentropic irrotational flow are generally undesirable in applied aerodynamics. Its occurrence should be delayed as much as possible by modifying the shape or contour of the body. However, such endeavor will be very much facilitated if the cause or the criterion for the breakdown can be found first.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/htc09-znt63Two-dimensional irrotational mixed subsonic and supersonic flow of a compressible fluid and the upper critical Mach number
https://resolver.caltech.edu/CaltechAUTHORS:20140805-133252590
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-Shen'}}, {'id': 'Kuo-Y-H', 'name': {'family': 'Kuo', 'given': 'Yung-Huai'}}]}
Year: 1945
The problem of flow of a compressible fluid past a body with subsonic flow at infinite is formulated by the hodograph method. The solution in the hodograph plane is first constructed about the origin by superposition of the particular integrals of the transformed equations of motion with a set of constants which would determine, in the limiting case, a known incompressible flow. This solution is then extended outside the circle of convergence by analytic continuation.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6c106-ame27Research in rocket and jet propulsion
https://resolver.caltech.edu/CaltechAUTHORS:JPC001
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-Shen'}}]}
Year: 1950
When considering the problems of basic research in rocket and jet propulsion, it is profitable to keep in mind the salient features of rocket- and jet-propulsion engineering. These are: short duration of operation of the power-plant and extreme intensity of reaction in the motor.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/399er-yc891A generalization of Alfrey's theorem for visco-elastic media
https://resolver.caltech.edu/CaltechAUTHORS:JPC002
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1950
For the non-homogeneous stresses in isotropic incompressible visco-elastic media characterized by linear relations between the components of stress, strain and their derivatives with respect to time, T. Alfrey has shown (Ref. 1) that in the case of the first boundary value problem, the stress distribution is identical with that in an incompressible elastic material under the same instantaneous surface forces. A similar result was obtained for the second boundary value problem where the displacements at the boundary are specified. It is the purpose of the present note to generalize this theorem to isotropic compressible media for problems involving body forces. Only the first boundary value problem will be discussed, as the corresponding theorem on the second boundary value problem is self-evident.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r7b0p-8ez76Instruction and research at the Daniel and Florence Guggenheim Jet Propulsion Center
https://resolver.caltech.edu/CaltechAUTHORS:JPC003
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-shen'}}]}
Year: 1950
In "America Fledges Wings" R. M. Cleveland [1] stated: "Despite the importance of the role played by the Daniel Guggenheim Fund for the promotion of aeronautics as a herald, as an awakener, as a quickening spark in the manifold fields of practical aviation, its most important and probably most lasting contribution lay in its implementation and its creation of centers of research."
These centers of research are the well-known great schools of aeronautical engineering at the New York University, the Stanford University, the University of Michigan, the Massachusetts Institute of Technology, the California Institute of Technology, the University of Washington, and the Georgia School of Technology. It is a fact that a great majority of practicing aeronautical engineers today are either wholly educated in one of these centers or have had contact with one of these centers. Moreover, the strong influence of the Guggenheim Fund is not limited to this phase of aeronautical engineering. These centers of research contributed to a large extent to the fundamental knowledge of aeronautical science which forms the scientific basis of aeronautical engineering. Today we see an even more broadened effect exerted by the Guggenheim schools as men originally educated in these Guggenheim research centers establish new research laboratories and new schools of aeronautics in universities all over the world.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vd0eg-3py51Instruction and research at the Daniel and Florence Guggenheim Jet Propulsion Center
https://resolver.caltech.edu/CaltechAUTHORS:JPC003
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-shen'}}]}
Year: 1950
In "America Fledges Wings" R. M. Cleveland [1] stated: "Despite the importance of the role played by the Daniel Guggenheim Fund for the promotion of aeronautics as a herald, as an awakener, as a quickening spark in the manifold fields of practical aviation, its most important and probably most lasting contribution lay in its implementation and its creation of centers of research."
These centers of research are the well-known great schools of aeronautical engineering at the New York University, the Stanford University, the University of Michigan, the Massachusetts Institute of Technology, the California Institute of Technology, the University of Washington, and the Georgia School of Technology. It is a fact that a great majority of practicing aeronautical engineers today are either wholly educated in one of these centers or have had contact with one of these centers. Moreover, the strong influence of the Guggenheim Fund is not limited to this phase of aeronautical engineering. These centers of research contributed to a large extent to the fundamental knowledge of aeronautical science which forms the scientific basis of aeronautical engineering. Today we see an even more broadened effect exerted by the Guggenheim schools as men originally educated in these Guggenheim research centers establish new research laboratories and new schools of aeronautics in universities all over the world.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fmq3k-h0y80Influence of flame front on the flow field
https://resolver.caltech.edu/CaltechAUTHORS:JPC004
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1951
Flame front is a region in the flow field where rapid change in the chemical composition of the fluid occurs with consequent release of chemical energy in the form of heat. In the majority of cases the phenomenon is a very complicated one involving the heat transfer by conduction and radiation, the changes in concentration of the different components by diffusion and chemical reaction. Owing to this and the difficult problem of chemical kinetics, only recently the complete theory of flame front has been formulated, particularly by the group under J. O. Hirschfelder.[2] Fortunately, as a result of the rapid rate of chemical reaction, the thickness of the flame front under ordinary conditions is generally very small, being less than 1 mm. Therefore, if one is interested in the influence of flame front on the flow field but not on the detailed structure of the flame, the flame can be assumed as infinitesimally thin, and only the final changes of the state of fluid due to combustion need be considered. This procedure is entirely analogous to that of treating the shock wave as having zero thickness in studying dynamics of compressible fluids. This simplification will be adopted for the present investigation.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f7sdr-vq641Optimum thrust programming for a sounding rocket
https://resolver.caltech.edu/CaltechAUTHORS:JPC006
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}, {'id': 'Evans-R-C', 'name': {'family': 'Evans', 'given': 'Robert C.'}}]}
Year: 1951
The problem of optimal thrust programming for a sounding rocket of minimum starting weight to reach specified height with given final weight and propellant characteristics is first formulated as a problem in variational calculus. The general solution for arbitrary drag function is given. The solution is then applied to two special cases, one with quadratic drag dependence on velocity and the other with linear drag dependence on velocity. Complete numerical data are given. The results are then compared with the results of constant thrust to show the advantages of thrust programming. Thrust programming is shown to be able to increase appreciably the pay load of a high altitude sounding rocket.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hkj2v-qpg48Optimum thrust programming for a sounding rocket
https://resolver.caltech.edu/CaltechAUTHORS:JPC006
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}, {'id': 'Evans-R-C', 'name': {'family': 'Evans', 'given': 'Robert C.'}}]}
Year: 1951
The problem of optimal thrust programming for a sounding rocket of minimum starting weight to reach specified height with given final weight and propellant characteristics is first formulated as a problem in variational calculus. The general solution for arbitrary drag function is given. The solution is then applied to two special cases, one with quadratic drag dependence on velocity and the other with linear drag dependence on velocity. Complete numerical data are given. The results are then compared with the results of constant thrust to show the advantages of thrust programming. Thrust programming is shown to be able to increase appreciably the pay load of a high altitude sounding rocket.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/na328-kde18The emission of radiation from diatomic gases. III. Numerical emissivity calculations for carbon monoxide for low optical densities at 300°K and atmospheric pressure
https://resolver.caltech.edu/CaltechAUTHORS:20090805-142635076
Authors: {'items': [{'id': 'Penner-S-S', 'name': {'family': 'Penner', 'given': 'S. S.'}}, {'id': 'Ostrander-M-H', 'name': {'family': 'Ostrander', 'given': 'M. H.'}}, {'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1952
DOI: 10.1063/1.1702185
Numerical emissivity calculations at 300°K and atmospheric pressure for nonoverlapping rotational lines have been carried out for CO using a dispersion formula for the line-shape representation. Use of the best available experimental data on integrated absorption and rotational line-width leads to calculated emissivities which are in excellent agreement with extrapolated empirical data published by Hottel and Ullrich. In particular, the theoretical dependence of emissivity on optical density, for small optical densities at 300°K, has been shown to follow experimental observations with satisfactory precision.For small optical densities the calculated emissivity is found to be proportional to the square root of the assumed rotational line-width, thus emphasizing the need for accurate line-width determinations at elevated temperatures. The limits of validity of the treatment utilizing nonoverlapping rotational lines are defined by examining overlapping between adjacent weak and strong rotational lines.The calculation of emissivities can be simplified by the use of approximate treatments. Thus absolute values of the emissivity can be predicted within 10 percent by utilizing a treatment for nonoverlapping, equally spaced, and equally intense lines, together with empirically determined values for the equivalent mean integrated absorption of the rotational lines of CO. A better analytic solution, which does not involve the assumptions of equal spacing and equal intensity of the rotational lines, has been obtained by utilizing asymptotic relations for large values of modified Bessel functions.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dywnh-xpg40The transfer functions of rocket nozzles
https://resolver.caltech.edu/CaltechAUTHORS:20091209-134942869
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1952
The transfer function is defined as the fractional oscillating mass flow rate divided by the fractional sinusoidal pressure oscillation in the rocket combustion chamber. This is calculated as a function of the frequency of oscillation. For very small frequencies, the transfer function is approximately 1 with a small "lead component." For very large frequencies, the transfer function is considerably larger than 1, and is approximately 1 + (γM_1)^(-1) where γ is the ratio of specific heats of the gas, and M_l is the Mach nUlllber at entrance to the nozzle.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9pdb4-q6p56On the Determination of Rotational Line Half-Widths of Diatomic Molecules
https://resolver.caltech.edu/CaltechAUTHORS:20091209-141443391
Authors: {'items': [{'id': 'Penner-S-S', 'name': {'family': 'Penner', 'given': 'S. S.'}}, {'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1952
DOI: 10.1063/1.1700578
A simple closed-form expression is obtained for the fractional intensity of radiation absorbed by vibration-rotation bands with collision-broadened spectral lines. The resulting expressions greatly reduced the labor involved in obtaining apparent rotational half-widths from experimental measurements.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3dp32-sm983A similarity law for stressing rapidly heated thin-walled cylinders
https://resolver.caltech.edu/CaltechAUTHORS:20091209-140147995
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}, {'id': 'Cheng-C-M', 'name': {'family': 'Cheng', 'given': 'C. M.'}}]}
Year: 1952
When a thin cylindrical shell of uniform thickness is very rapidly heated by hot high-pressure gas flowing inside the shell, the temperature of material decreases steeply from a high temperature at the inside surface to ambient temperatures at the outside surface. Young's modulus of material thus varies. The purpose of the present paper is to reduce the problem of stress analysis of such a cylinder to an equivalent problem in conventional cylindrical shell without temperature gradient in the wall. The equivalence concept is expressed as a series of relations between the quantities for the hot cylinder and the quantities for the cold cylinder. These relations give the similarity law whereby strains for the hot cylinder can be simply deduced from measured strains on the cold cylinder and thus greatly simplify the problem of experimental stress analysis.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t6fjj-ggz80Automatic navigation of a long range rocket vehicle
https://resolver.caltech.edu/CaltechAUTHORS:20091210-142418746
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}, {'id': 'Adamson-T-C', 'name': {'family': 'Adamson', 'given': 'T. C.'}}, {'id': 'Knuth-E-L', 'name': {'family': 'Knuth', 'given': 'E. L.'}}]}
Year: 1952
The flight of a rocket vehicle in the equatorial plane of a rotating earth is considered with possible disturbances in the atmosphere due to changes in density, in temperature, and in wind speed. These atmospheric disturbances together with possible deviations in weight and in moment of inertia of the vehicle tend to change the flight path away from the normal flight path. The paper gives the condition for the proper cut-off time for the rocket power, and the proper corrections in the elevator angle so that the vehicle will land at the chosen destination in spite of such disturbances. A scheme of tracking and automatic navigation involving a high-speed computer and elevator servo is suggested for this purpose.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r4pfn-t9g52A method for comparing the performance of power plants for vertical flight
https://resolver.caltech.edu/CaltechAUTHORS:20091211-152054111
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1952
A new method of power plant selection for vertical flight is proposed. It can be used to determine whether the performance of a rocket design can be improved by substituting for the rocket motor a different power plant such as a ramjet. Calculations indicate that there are advantages in using the ramjet provided the power plant can be made to operate under rapid acceleration and at high altitudes.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d7s2x-d3p24Servo-stabilization of combustion in rocket motors
https://resolver.caltech.edu/CaltechAUTHORS:20091214-130734801
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1952
This paper shows that the combustion in the rocket motor can be stabilized against any value of time lag in combustion by a feedback servo link from a chamber pressure pickup, through an appropriately designed amplifier, to a control capacitance on the propellant feed line. The technique of stability analysis is based upon a combination of the Satche diagram and the Nyquist diagram. For simplicity of calculation, only low-frequency oscillations in monopropellant rocket motors are considered. However, the concept of servo-stabilization and method of analysis are believed to be generally applicable to other cases.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d8bes-azq17The Properties of Pure Liquids
https://resolver.caltech.edu/CaltechAUTHORS:20091214-143421207
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1953
By a semiempirical approach, a method is found to calculate the specific heat of a normal pure liquid at constant pressure form the specific heat of the gaseous state at the same temperature. It is also found that the coefficient of thermal expansion, the compressibility, and the velocity of sound of the liquid can be calculated accurately if the density, the molecular weight, and the normal boiling temperature of the liquid at atmospheric pressure are known. Finally, a method of computing the thermal conductivity of all liquids, except liquid metals, from compressibility and density is developed. For normal liquids, the thermal conductivity can again be determined if only the normal boiling temperature, the density, and the molecular weight are known.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v2ktf-kdq53Similarity Laws for Stressing Heated Wings
https://resolver.caltech.edu/CaltechAUTHORS:20091214-142900787
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1953
It will be shown that the differential equations for a heated plate with large temperature gradient and for a similar plate at constant temperature can be made the same by a proper modification of the thickness and the loading for the isothermal plate. This fact leads to the result that the stresses in the heated plate can be calculated from measured strains on the unheated plate by a series of relations, called the "similarity laws." The application of this analog theory to solid wings under aerodynamic heating is discussed in detail. The loading on the unheated analog wing is, however, complicated and involves the novel concept of feedback and "body force" loading. The problem of stressing a heated box-wing structure can be solved by the same analog method and is briefly discussed.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/kckct-kv795Physical Mechanics, a New Field in Engineering Science
https://resolver.caltech.edu/CaltechAUTHORS:20091214-144949544
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1953
The purpose of physical mechanics is to predict the engineering behavior of matter in bulk form from the microscopic properties of its molecular and atomic constituents. The constants and basic concepts of this new engineering science, of particular importance to rocket and jet propulsion, are discussed in this paper.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5z1qt-rqq76Take-Off from Satellite Orbit
https://resolver.caltech.edu/CaltechAUTHORS:20091215-133451765
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1953
The mass ratio or the characteristic velocity for the take-off of a space ship from the satellite orbit is computed for two cases: the radial thrust, and the circumferential thrust. The circumferential thrust is much more efficient in that the required mass ratio is much less than for the radial thrust. Both cases show, however, an increase of the required mass ratio and the characteristic velocity with a reduction in acceleration. With circumferential thrust, the characteristic velocity increases by a factor of two, when the acceleration is reduced from 1/2 g to 1/3000 g.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cen1e-gq507Analysis of peak-holding optimalizing control
https://resolver.caltech.edu/CaltechAUTHORS:20110119-105101344
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}, {'id': 'Serdengecti-S', 'name': {'family': 'Serdengecti', 'given': 'S.'}}]}
Year: 1955
The peak-holding optimalizing control is analyzed under the
assumption of first-order input linear group and output linear group. Design charts are constructed for determining the required input drive speed and the consequent hunting loss with specified time constants of the input and output linear groups, the hunting period, and the critical indicated difference for input drive reversal.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/q67xp-4kz55Thermodynamic properties of gas at high temperatures and pressures
https://resolver.caltech.edu/CaltechAUTHORS:20110119-111358754
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 1955
N/Ahttps://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/60qyq-va070Thermonuclear power plants
https://resolver.caltech.edu/CaltechAUTHORS:20110118-092852136
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'Hsue-Shen'}}]}
Year: 1956
Some of the unique features of thermonuclear power
plants and the essential problems in the technical design
of such plants are discussed in this paper. The thermonuclear reaction rate for the fusion of deuterium is calculated on the basis of a similar analysis published by Gamow and Teller. The pressure, temperature, and minimum
dimensions of the necessary reaction chamber are determined
largely by consideration of reaction quenching and energy loss near the walls. Results are presented for the power output and the efficiency of a power station utilizing
the deuterium fusion reaction. The comment by
Greenstein that follows this paper deals particularly with
the difficult problem of calculating the reaction quenching
and energy loss rates at the walls.https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d1r5a-anb69Lecture Notes on Applications of Jet Propulsion Power Plants
https://resolver.caltech.edu/CaltechAUTHORS:20151111-143742969
Authors: {'items': [{'id': 'Tsien-H-S', 'name': {'family': 'Tsien', 'given': 'H. S.'}}]}
Year: 2015
[no abstract]https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cz38v-1b837