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C Ţicleanu horizontal illuminance within the axis of the main light-pipe was measured at certain distances from the diamond dome. In order to assess the potential of light distribution through the horizontal branches, vertical illuminance on the inner wall of the lightpipe was measured at certain distances from the diamond dome. Basing on these values, a recurrence law was found to predict the illuminance at a certain point of the light-pipe for a certain value of the external horizontal illuminance at roof level. If E0 is the external horizontal illuminance at roof level, then the horizontal illuminance Eh,l within the lightpipe axis at the distance l from the diamond dome will be Eh , l = E0 − ϕ() l (4) where ϕ(l) is the recurrence function determined using the CurveExpert 1.3 software based on the Levenberg- Marquardt method of nonlinear regression. The same applies for the vertical illuminance Ev,l on the inner wall of the main light-pipe, which at the distance l from the diamond dome will be Ev , l = E0 −ψ () l (5) where the recurrence function ψ(l) was determined using the same method as above. Beside the light transmission of the main light-pipe, the transmission characteristics of the secondary branch pipe were assessed. Basing on the same algorithm, the illuminance Ebδ at the distance δ from the ramification within the axis of the branch was expressed as a function of the initial illuminance Eb at the entrance in the branch and the distance δ: 42 INGINERIA ILUMINATULUI 18-2006 ( δ ) E b, δ = Eb − β (6) where the recurrence function β(δ) results using the same algorithm as for the main light-pipe. The first measurements were taken using a 75 W incandescent lamp as the light source for the main duct. The illuminance within the axis of the light-pipe at the distance L=23 cm from the lamp socket’s base plane was considered as the initial illuminance E0. Several measurements were taken and the mean values are shown in the table below. Horizontal illuminance within pipe axis L, cm l, cm Eh,l, cm ΔEh, cm 23 0 31,500 0 33 10 29,533 1967 43 20 28,467 3033 53 30 27,733 3767 63 40 25,833 5667 73 50 24,333 7167 Vertical illuminance on pipe’s inner wall L l Ev,l ΔEv 23 0 12,000 19,500 33 10 9750 21,750 43 20 8850 22,650 53 30 8425 23,075 63 40 8150 23,350 73 50 7875 23,625 L is the distance from the socket’s base plan at which the horizontal and vertical illuminances Eh,l and Ev,l are measured, l is the length at the measurement point relative to the point where the initial illuminance E0 is measured, and ΔEh and ΔEv are the differences of illuminance E0–Eh,l and E0– Ev,l respectively. In order to see the light amplification effect specific to the SunPipe, the table below shows the illuminance generated by
the same incandescent lamp at the same distances as above, but in the absence of the SunPipe, and the amplification factor AF of the SunPipe: Horizontal illuminance generated by the 75 W incandescent lamp L, cm l, cm Eh,l,il, lx AF 23 0 5600 5.63 33 10 2250 13.13 43 20 1380 20.63 53 30 950 29.19 63 40 730 35.39 73 50 520 46.79 The light amplification factor AF is given by Eh,l/Eh,l,il. For the measured values, the CurveExpert 1.3 software generated the recurrence functions using the Levenberg- Marquardt method of nonlinear regression for 23 regression models. The most accurately found form for the horizontal illuminance function was: () ( ) c ϕ l = a l − b (7) if using the shifted power fit, with 0.9919 correlation coefficient, where: a=39.358572 b=-10.332781 c=1.2648536 The most accurately found form for the vertical illuminance function was: () ( ) c −1 ψ l = a + bl (8) if using the Bleasdale model of regression, with 0.8927 correlation coefficient, where: a=0.80990555 b=-5.5413364e -005 c=0.021229594 Approach on numerical modelling Afterwards, the branched SunPipe system was supplied with daylight from the diamond dome light collecting unit. The horizontal branch was located at three metres from the roof level and two situations were assessed: A – branch without mirror B – branch equipped with mirror The mirror was made of the same material as the SunPipe (Super Silver mirrored aluminium) and was installed at the entrance of the branch at 45 degrees rotation relative to the horizontal (see Figure 4). SunPipe main duct SunPipe branch Super Silver aluminium mirror Figure 4 Mirror-supplied SunPipe branch. The mean values of the illuminance measured within the axis of the branch for the two situations, at the same level of external horizontal illuminance at roof level of 85,000, are shown in the table below. Branch illuminance, lx δ, cm without mirror with mirror 0 8600 13,000 17 8400 13,300 27 9100 14,800 37 8900 13,700 For the branch supplied with light directly from the main light-pipe, without a mirror, the most accurate form for the INGINERIA ILUMINATULUI 18-2006 43
Page 2 and 3: Editorial Board Florin POP, Profess
Page 5 and 6: INGINERIA ILUMINATULUI Lighting Eng
Page 7 and 8: LIGHTING BETWEEN THE ENERGY EFFICIE
Page 9 and 10: CREFEN - AN INFORMATIC SYSTEM FOR E
Page 11 and 12: European experience on the energy e
Page 13 and 14: 4. Results after the first year of
Page 15 and 16: (No. of questionnaires) 70 60 50 40
Page 17 and 18: have defined your specific needs. T
Page 19 and 20: and was scientist in charge of 9 Eu
Page 21 and 22: RECENT DEVELOPMENTS IN DAYLIGHT GUI
Page 23 and 24: Design guidance for conventional gl
Page 25 and 26: Figure 5 a Recent work at Liverpool
Page 27 and 28: Figure 6 It could be argued that th
Page 29 and 30: INFLUENCE OF THE COLOUR TEMPERATURE
Page 31 and 32: meant that during the total period
Page 33 and 34: was during the official breaks. Tho
Page 35 and 36: considerably more noticeable. When
Page 37 and 38: one colour temperature. So even if
Page 39 and 40: 3. Berman, S.M., Navvab, M., Martin
Page 41 and 42: APPROACH ON NUMERICAL MODELLING OF
Page 43 and 44: Tests carried out by the BRE (Build
Page 45: where NP is the number of parameter
Page 49 and 50: 7. Ticleanu, C., Modern Daylighting
Page 51 and 52: SCIENTIFIC BOARD Wout van BOMMEL, T
Page 53 and 54: Conferences and Symposiums The 4th
Page 55 and 56: Information Figure 2 Airfield light
Page 57 and 58: Information Figure 7 Radio wireless
Page 59 and 60: Annex 1 CCR Figure 1A1 Serial power
Page 61 and 62: STREET LIGHTING DIMMING Information
Page 63 and 64: If the luminaire has been turned of
Page 65 and 66: current power consumption (savings
Page 67 and 68: 2 The features of the ALADIN protot
Page 69 and 70: Graphical interface Psiho phisiolog

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