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Trajectory equations

The ratio to z depends only on (gag-, zjx, = 2/3 tga.g, and the ratio of x, /Xq has a constant value equal to 0.578. To clarify the trajectory equation of inclined jets for the cases of air supply through different types of nozzles and grills, a series of experiments were conducted. The trajectory coordinates were defined as the points where the mean values of the temperatures and velocities reached their maximum in the vertical cross-sections of the jet. It is important to mention that, in such experiments, one meets with a number of problems, such as deformation of temperature and velocity profiles and fluctuation of the air jet trajectory, which reduce the accuracy in the results. The mean value of the coefficient E obtained from experimental data (Fig. 7.25) is 0.47 0.06. Thus the trajectory of the nonisothermal jet supplied through different types of outlets can be calculated from... [Pg.467]

For rhe non isothermal linear air jet, the trajectory equation is derived bv Shepelev" is... [Pg.469]

Scientific theories themselves can be distinguished as deductive or inductive in nature, according to the underlying character of their premises. In a deductive theory, the fundamental premises are axioms or postulates that are neither questionable nor explainable within the theory itself. Outstanding examples of deductive theories include Euclidean geometry (based on Euclid s five axioms) and quantum mechanics (based on Schrodinger s prescription for converting classical trajectory equations into wave equations). An inductive theory, on the other hand, is based on universal laws of experience that express what has always been found to be true in the past, and may therefore be reasonably expected to hold in the future. Thermodynamics is the pre-eminent example of an inductive theory. [Pg.17]

If there is a racemizing cross-catalysis (Eq. 5) with k 2, the trajectory equation is rewritten as ... [Pg.107]

Total scattering efficiency, 282 Toxic doses, estimation of, 124-125 Tracheobronchial tree, 125 Trajectories equation for, 80 phase, 108-113 two-dimensional, 140-141 Transfer of energy, 40 Transfer of mass, 40 Transfer of momentum, 34, 40, 49,166, 168, 341... [Pg.202]

In discussing the alternative theoretical approaches let us limit ourselves to those which have been applied directly to processes in which we are interested in this article, but first of all let us stress once more the importance of the work of Delos and Thorson (1972). They formulated a unified treatment of the two-state atomic potential curve crossing problem, reducing the two second-order coupled equations to a set of three first-order equations. Their formalism is valid in the diabatic as well as the adiabatic representation and also at distances of closest approach near Rc. Moreover the problem of the residual phase x(l) is solved implicitly. They were able to show that a solution of the three first-order classical trajectory equations is not sensitive to all details of the potentials and the coupling term, but to only one function which therefore can be used readily for modelling assumptions. The resulting equations should be solved numerically. Their method has been applied now to the problem of the elastic scattering of He+ + Ne (Bobbio et at., 1973) but unfortunately not yet to any ionization problem. [Pg.480]

The main practical problem in the implementation of the mixed quantum-classical dynamics method described in Section 4.2.4 is the nonlocal nature of the force in the equation of motion for the stationary-phase trajectories (Equation 4.29). Surface hopping methods provide an approximate, intuitive, stochastic alternative approach that uses the average dynamics of swarm of trajectories over the coupled surfaces to approximate the behavior of the nonlocal stationary-phase trajectory. The siu--face hopping method of Tully and Preston and Tully describes nonadiabatic dynamics even for systems with many particles. Commonly, the nuclei are treated classically, but it is important to consider a large niunber of trajectories in order to sample the quantum probability distribution in the phase space and, if necessary, a statistical distribution over states. In each of the many independent trajectories, the system evolves from the initial configuration for the time necessary for the description of the event of interest. The integration of a trajec-... [Pg.184]

Hybrid Quantum/Classical Dynamics Using Bohmian Trajectories Equation (22) is then equivalent to... [Pg.339]

In the following we shall therefore assume that equations (1) are the differential equations of empty space. Empty in this case implies the absence of both matter and electric density. The field equations and the trajectory equations of electrical particles are only valid in this case. [Pg.371]

Similarly the limiting trajectory equations for laminar flow between parallel plates or in shallow trays and for uniform flow (i.e. u/Vo = 1) are of the foim ... [Pg.247]

However the transition fi om flow to laminar flow can be ejq>ected to proceed via uniform conditions which will provide similar trajectory equations to those fi>r laminar flow so in practical terms it is only necessary to ensure the elimination of turbulent flow at the entry to the separation section. [Pg.249]

We now consider the special case of rotationally symmetric systems in the paraxial approximation that is, we examine the behavior of charged particles, specifically electrons, that remain very close to the axis. For such particles, the trajectory equations collapse to a simpler form, namely. [Pg.6]

Contribution to the fundamental science will influence development of macrscopic kinetics, classical equilibrium thermodynamics, and joint application of these disciplines to study the macroworld. The capabilities of kinetic analysis will be surely expanded considerably, if traditional kinetic methods that are reduced to the analysis of trajectory equations are sup>plemented by novel numerical methods. The latter are to be based on consideration of continuous sequences of stationary processes in infinitesimal time intervals. The problems of searching for the trajectories, being included into the subject of equilibrium thermodynamics, would make deserved the definition of this discipline as a closed theory that allows the study of any macroscopic systems and processes on the basis of equilibrium principles. Like the equilibrium analytical mechanics of Lagrange the thermodynamics may be called the unified theory of statics and dynamics. Joint application of kinetic and thermodynamic models further increases the noted potential advantages of the discussed directions of studies. [Pg.56]

We have established in the preceding discnssion that the second-order trajectory Equation 4.11 implies the first-order law (Equation 4.17), where the potential S is determined by Eqnation 4.18. The converse is trivially proved Given Equations 4.17 and 4.18, we can deduce Equation 4.11 by differentiation. Hence, the first- and second-order formulations are formally equivalent. Each may have advantages where the other is deficient. For example, if we wish to compute the trajectories, knowing only Vo and withont invoking the Eulerian equations as aids, the second-order version must be used. On the other hand, if we desire to compute the trajectories from a known wave fnnction, the first-order version may be preferable. It would artificially restrict the insights and opportunities afforded by quantum hydrodynamics to treat one law as more fundamental than the other, either conceptually or computationally. [Pg.64]

Of course, correct solutions to Kelvin s equation never produce such results. Since its trajectory equations require that f move with the particle and remain unchanged, it is clear that red water must remain red water and blue water will always be blue water. Precise methods are available to solve Kelvin s equation. For example, conservation laws of the form W( + F(W) x = 0 where... [Pg.74]

Deterministic modelling of the flight of the fragment (i.e. derivation of the trajectory equation for the fragment) ... [Pg.1378]

In order to derive the trajectory equation of a fragment, its shape and angle of departure must be known. [Pg.1378]


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See also in sourсe #XX -- [ Pg.52 ]




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