diff --git a/Bouchair_Solar_Chimney/Bouchair_Heat_Transfer_Coefficients.csv b/Bouchair_Solar_Chimney/Bouchair_Heat_Transfer_Coefficients.csv new file mode 100644 index 000000000..861bca895 --- /dev/null +++ b/Bouchair_Solar_Chimney/Bouchair_Heat_Transfer_Coefficients.csv @@ -0,0 +1,25 @@ +case,inlet_height_m,cavity_gap_m,wall_temperature_C,mdot_exp_kg_s_m,mdot_exp_kg_s,htc_exp_W_m2_K,thesis_table +SC_p1_p1_30,0.1,0.1,30,0.049,0.0735,6.7,4.29 +SC_p1_p1_40,0.1,0.1,40,0.065,0.0975,8.2,4.29 +SC_p1_p1_50,0.1,0.1,50,0.080,0.1200,8.9,4.29 +SC_p1_p1_60,0.1,0.1,60,0.090,0.1350,9.8,4.29 +SC_p1_p2_30,0.1,0.2,30,0.060,0.0900,7.0,4.29 +SC_p1_p2_40,0.1,0.2,40,0.082,0.1230,7.9,4.29 +SC_p1_p2_50,0.1,0.2,50,0.099,0.1485,9.3,4.29 +SC_p1_p2_60,0.1,0.2,60,0.110,0.1650,9.7,4.29 +SC_p1_p3_30,0.1,0.3,30,0.059,0.0885,5.6,4.29 +SC_p1_p3_40,0.1,0.3,40,0.080,0.1200,6.5,4.29 +SC_p1_p3_50,0.1,0.3,50,0.095,0.1425,7.4,4.29 +SC_p1_p3_60,0.1,0.3,60,0.109,0.1635,7.8,4.29 +SC_p4_p1_30,0.4,0.1,30,0.046,0.0690,4.9,4.30 +SC_p4_p1_40,0.4,0.1,40,0.067,0.1005,5.9,4.30 +SC_p4_p1_50,0.4,0.1,50,0.080,0.1200,6.6,4.30 +SC_p4_p1_60,0.4,0.1,60,0.086,0.1290,6.8,4.30 +SC_p4_p2_30,0.4,0.2,30,0.064,0.0960,6.1,4.30 +SC_p4_p2_40,0.4,0.2,40,0.094,0.1410,6.7,4.30 +SC_p4_p2_50,0.4,0.2,50,0.103,0.1545,7.0,4.30 +SC_p4_p2_60,0.4,0.2,60,0.118,0.1770,7.5,4.30 +SC_p4_p3_30,0.4,0.3,30,0.053,0.0795,4.5,4.30 +SC_p4_p3_40,0.4,0.3,40,0.097,0.1455,6.1,4.30 +SC_p4_p3_50,0.4,0.3,50,0.107,0.1605,6.5,4.30 +SC_p4_p3_60,0.4,0.3,60,0.121,0.1815,6.7,4.30 diff --git a/Bouchair_Solar_Chimney/README.md b/Bouchair_Solar_Chimney/README.md new file mode 100644 index 000000000..32786a4d7 --- /dev/null +++ b/Bouchair_Solar_Chimney/README.md @@ -0,0 +1,47 @@ +# Global convective heat transfer coefficients + +Source: A. Bouchair, thesis, `Bouchair_THESIS_uk_bl_ethos_329792.pdf`, +Tables 4.29 and 4.30, printed page 104 (PDF page 113). The CSV transcribes +all 24 HTC values and their accompanying mass flow rates as printed. +HTC units are W/(m2 K). `mdot_exp_kg_s_m` is mass flow per unit cavity +span in kg/(s m). `mdot_exp_kg_s` is the total mass flow in kg/s, calculated +as `mdot_exp_kg_s_m * 1.5 m`. + +The four columns correspond to wall temperatures 10, 20, 30, and 40 K above +20 C ambient, mapped here to FDS case temperatures 30, 40, 50, and 60 C. +See also Tables 4.25 and 4.26 (printed page 99) and Tables 4.33 and 4.34 +(printed page 107). The mass flows are retained from the HTC tables: +Table 4.29 gives 0.095 for the 0.1 m inlet, 0.3 m gap, 50 C case, whereas +Table 4.25 gives 0.097; Table 4.30 gives 0.053 for the 0.4 m inlet, 0.3 m +gap, 30 C case, whereas Table 4.26 gives 0.060. No corrections are applied. + +Equation 4.3, printed page 103 (PDF page 112), defines + + hc = M cp (T_out - T_in) / [2 Y Z (T_wall - T_bulk)] + T_bulk = (T_in + T_out)/2 + +For total mass flow M in kg/s, use cavity span Y=1.5 m and height Z=2.0 m, +giving a nominal two-wall area of 6 m2. Equivalently, flow per unit span +uses area per unit span 2Z=4 m. The companion FDS script uses total `mdot`, +cp=1000 J/(kg K), T_in=20 C, and separate temporal means of `mdot` and +the spatially averaged `T_outlet` over the last half of the available run. +The area follows Eq. 4.3 without deducting the cavity inlet opening. + +Bouchair excludes 0.5 and 1.0 m gaps from these HTC tables because of +flow complexity (printed page 103); no experimental HTC is assigned to them. + +## Python comparison plot + +`Utilities/Python/scripts/bouchair_htc.py` in the FDS repository writes +`Bouchair_HTC.csv` and `Bouchair_HTC.pdf`. The PDF plots positive matched +experimental/predicted HTC pairs on equal log scales. Black lines show +unity and experimental spread; red lines show model bias and model spread. +The statistics use the ten-bin weighting and log-ratio formulas from +`fdsplotlib.scatplot`. Dashed bounds use factors `1+2*sigma`, as in FDS. + +Supply `--sigma-e` as a relative standard deviation (fraction) when an HTC +experimental uncertainty is available. If omitted, the FDS fallback sets +experimental and model variances equal to half the log-ratio variance; +the PDF explicitly labels the experimental uncertainty as estimated. +This fallback is not a thesis-reported uncertainty. The 0.08 mass-flow +uncertainty from the reference figure is not assigned to HTC.