Deviation angle

Between the top hole and the reservoir section in most cases an intermediate section will need to be drilled. This section consists of more consolidated rocks than the top hole. The deviation angle is often increased in this interval to reach the subsurface target and eventually a casing is set prior to entering the reservoir sequence. 

Wells may be drilled at a constant angle to the target or dropped off to a lower angle through the reservoir section. To build, maintain or drop the deviation angle stabilisers are run in the bottom hole assembly (Fig. 3.15). A change in deviation used to require a round trip to change the position of those stabilisers in the bottom hole assembly. In recent years, adjustable, hydraulically activated stabilisers have been developed. The... 

High deviation angles (above 60°) may cause excessive drag or torque while drilling, and will also make it difficult to later service the well with standard wireline tools. 

Carter s rule, which shows that the deviation angle is directly a function of the camber angle and is inversely proportional to the solidity 8 = mQ Xja) has been modified to take into account the effect of stagger, solidity, Mach number, and blade shape as shown in the following relationship ... 

To apply Equation (3), it is necessary to determine the diffusion coefficients Oy and o. The diffusion coefficients can be related to the deviation in the wind direction, given by o, in the azimuth angle (azimuth refers to the lateral or cross-wind direction), and o in the deviation angle (deviation refers to... 

Accelerometer Output for 30° of Hole Deviation Angle and Various Tool-Face Angles... 

Here 80 is the deviation angle from the Bragg condition. S is negative for positive A and positive for negative A. 

Note 3 Surface pretilt is the deviation angle of the director away from the surface. It is used to control the threshold voltage and affects viewing angles. 

Silyl radicals (1) are generally tetrahedral species. Deviation angles (y) have been calculated (UHF/DZP the DZP basis set is a double-zeta basis set with polarization functions) by Guerra to range from 13.4°[(H3Si)3Si ] to 22.7°[(PH2)3Si ]5. 

Prisms and Gratings. For a prism of refractive index n and refracting angle a, there is an angle of incidence 0 for which the deviation angle S is a minimum this can be used, for example, to determine the refractive index n of a liquid placed inside the hollowed prism (Fig. 2.19). 

Chronodeflectogram — A deflection signal where the deviation angle (6) of a probe laser beam is plotted as a function of time. It is also called chronodeflectomet-ric profile or PBD transient and is usually characterized by the presence of the - PBD maximum (or minimum) during the time evolution of the deflection signal [i]. See also - chronodeflectometry. 

Ifeble 5.4 Deviation angles of spin, orbital and total moment calculated with the MASW method. Hie last column gives experimental values (Gukasov et al. 1996 Wisniewski et al. 1999). 

The probability that an incident particle with wave number k will be scattered by the sample with a deviation angle 0 is... 

If the crystal is close to, but not exactly at, the phase matching orientation relative to k(u> 1), then a weak 2aq beam will be generated propagating at a small angle relative to k(u 1). Minimization of this deviation angle provides a basis for servo-correction of the crystal orientation to maximize SHG. It also ensures that, as uq is scanned, the 2u>i beam pointing direction is constant, which is good news for multiple resonance schemes that require careful superposition of several beams of laser radiation. 

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