Non-homogeneous paths Sample Clauses

Non-homogeneous paths. In this case, the equivalent distance or Kirke method shall be used. To apply this method, Figure 2.1 can also be used. Consider a path whose sections S1 and S2 have lengths d1 and (d2- d1), and conductivities F1 and F2 respectively, as shown on the following figure: S1 (F1) S2(F2) The method is applied as follows: (a) taking section S1 first, we read the field strength corresponding to conductivity F1 at distance d1 on figure 2.1; (b) as the field strength remains constant at the point of discontinuity, the value immediately after the discontinuity must be equal to that obtained in (a) above. As the conductivity of the second section is F2, the curve corresponding to conductivity F2 gives the equivalent distance to that which would be obtained at the same field strength arrived at in (a). This equivalent distance is d. Distance d is larger than d1 when F2 is larger than F1. Otherwise d is less than d1; (c) the field strength at the real distance d 2 is determined by taking the corresponding curve for conductivity F2 and reading off the field strength obtained at the equivalent distance d + (d2 - d1); (d) for successive sections with different conductivities, procedures (b) and (c) are repeated. N.B. THE ORIGINAL FOR THIS FIGURE WILL BE MADE AVAILABLE LATER BY THE FCC. Figure 2.1 N.B. THE ORIGINAL FOR THIS FIGURE WILL BE MADE AVAILABLE LATER BY THE FCC. Figure 2.2 - Scales for use with Figure 2.1
Non-homogeneous paths. In this case, the equivalent distance or Kirke method is to be used. To apply this method, graphs 1 to 20 can also be used. Consider a path whose sections S1 and S2 have endpoint lengths corresponding to d1 and d2 – d1, and conductivities σ1 and σ2 respectively, as shown on the following figure: S1(σ1) d1 <–––––––––––––––––––––––––––––––––> S2(σ2) d2 <–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––> Tx Rx The method is applied as follows: a) Taking section S1 first, we read the field strength corresponding to conductivity σ1 at distance d1 on the graph corresponding to the operational frequency. b) As the field strength remains constant at the soil discontinuity, the value immediately after the point of discontinuity must be equal to that obtained in a) above. As the conductivity of the second section is σ2, the curve corresponding to conductivity σ2 gives the equivalent distance to that which would be obtained at the same field strength arrived at in a). This equivalent distance is d. Distance d is larger than d1 when σ2 is larger than σ1. Otherwise d is less than d1. c) The field strength at the real distance d2 is determined by taking note of the corresponding curve for conductivity σ2 similar to that obtained at equivalent distance d + (d2 – d1). d) For successive sections with different conductivities, procedures b) and c) are repeated.