Velocity errors

The pitot-static tube is also sensitive to yaw or angle of attack than is the simple pitot tube because of the sensitivity ofthe static taps to orientation. The error involved is strongly dependent upon the exac-t probe dimensions. In general, angles greater than 10° should be avoided if the velocity error is to be 1 percent or less. 

In many control texts, we also find the derivation of the velocity error constant (using R = s-2) and acceleration error constant (using R = s-3), and a subscript p is used on what we call Kerr here. 

It is apparent that for a given set of 9 and y, the phase-velocity error can be zeroed if a, b are appropriately selected. This implies that one may solve for a, b from (2.82) or define the dispersion error... 

T. Kashiwa, H. Kudo, Y. Sendo, T. Ohtani, and Y. Kanai, The phase velocity error and stability condition of the three-dimensional nonstandard FDTD method, IEEE Trans. Magn., vol. 38, no. 2, pp. 661-664, Mar. 2002.doi 10.1109/20.996172... 

The performance of the material-correction schemes is examined via various 2- and 3-D examples. Figure 5.4(a) presents the phase-velocity error of the (2, 4) FDTD, before and after the material modification, for a cubic lattice with a size of X /8. The selected angles of propagation (9m, axis scaling of the two figures, the improvement is quite satisfactory and most importantly, all... 

FIGURE 5.4 (a) Phase-velocity error of the conventional (2, 4) and the material-correction FDTD method, respectively, (b) Wideband performance of various (2, 4) FDTD implementations... 

TABLE 5.5 Numerical Phase-Velocity Error for a 3-D Uniform Lattice ... 

TmeEffects, that allows the computation of the interferograms in a way that time effects such as the drive velocity errors can be included in the simulation. DetectorEffects, to create a set of interferograms including all the detector effects (otherwise the simulator returns the raw interferograms, which is described later in this chapter). 

If the interferograms have been distorted due to errors in the FTS drive, at this point it is necessary to interpolate the interferograms to a continuous optical delay line. Figure 5.4 shows the effects of errors in the velocity of the drive (bottom) and the ideal interferogram (top) for the previous simulation. A disproportionate velocity error of 30 % has been applied to increase the visual effect. It can be observed that the sampling points are not equidistant, which without correction will alter the detected spectrum. 

The inputs variables of the FLC correspond to the velocity errors obtained of (5.6) (denoted as ev and ew linear and angular velocity errors respectively), and 2 outputs variables, the driving and rotational input torques t (denoted by F and N respectively). 

We will call Cases to the group of simulations realized under the same parameters. Case 1 corresponds to the gain constants found by the CRA applying only the decomposition reaction in experiment No. 6 these gains obtained the smallest velocity error (8.13e-005). 

Case 2 corresponds to the gain constants that obtained a smaller error for theta in experiment No. 3 (0.0315) but not a small velocity error (0.0025796). 

Case 3 corresponds to the gain constants found by the CRA applying all the decomposition reactions and whose parameters found the smaller velocity error (1.3092E-08). To evaluate each case, we use the average error given by Eq. (6.1). 

For Case 1, the minimum error value found by the chemical reaction algorithm was 0.89855. Figure 6.13 shows the resulted input membership functions found by the proposed optimization algorithm for the linear and angular velocity errors. 

Fig. 6.13 Input membership functions a linear and b angular velocity errors for Case 1...

However, experimental methods for a quite accurate determination of the detonation velocity (errors less than 1%), mass velocity, and the detonation pressure (errors less than 3%) have been developed. For the last fifteen years, efforts have been directed towards the stutfy of detonation wave structure, i.e., the chemical spike and chemical reaction zone. Unfortunately, the time resolution slightly below 10 seconds, achievable by the most recent measuring techniques, is still insufficient for a reliable stuchemical spike and occasionally in the chemical reaction zone. 

Xt is interssfdng to caaapare the static velocity error constants for the tso systess designed above. 

Oeezly the velocity error consLanb K, the oGBpensated eyebea is... 

Some interferometers have been designed where the beam is dispersed across a linear array detector so that the interferogram is measured simply by reading the signal at each detector element without scanning any type of optical element. Such stationary interferometers are very attractive, as there are no moving parts and hence they are not susceptible to velocity errors. 

L. M. Logan, Signal-to-noise enhancement of Fourier transform spectroscopy (FTS) by electrical filter compensation of slide velocity errors, in Multiplex and/or High Throughput Spectroscopy, G. A. Vanasse, Ed., Society of Photo-Optical Instrumentation Engineers, Bellingham, WA, 1979, Vol. 191, p. 110. 

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