Simplified analysis of heat transfer through a finned tube bundle in air cooled condenser-second assessment

Abstract

This paper present a review of mathematical procedures for heat transfer studies in cross flow through finned tube pack. Is given a new model for heat transfer calculations during airflow through finned tubes bank in air cooled condenser systems (ACC). The model was correlated with a total of 783 sets of available experimental data provided by ten authors of recognized prestige in the research area. The air flow bathes a package of finned tubes with an inclination of 45 0 to 60 0 with respect to the horizontal line. The studies were performed for ST/SL intervals between 0.4 and 2, air flow velocity of 0.1 to 100 m/s, an ambient temperature of 15 to 43°C, the incident wind velocity over the installation between 0 and 45 km/h, the outer equivalent diameter of the bare tubes between 0.019 and 0.05 m, a fins height between 2.7 and 7.9 mm.The fins thicknesses ranging between 1.3 and 3.5 mm and a number of fins per unit tube length between 315 and 394. The mean deviation found was 6.9% in 85.3% of the correlated experimental data.

Methods for the Determination of the Heat Transfer Coefficient in Air Cooled Condenser Used at Biomass Power Plants

“…In these , it is confirmed that the model given by Camaraza et al (Eq. ( 3)) [14] have the best MAE adjustment values, showing an average error of 7.6% and 7.2% in the correlation with available experimental data for zones 1 and 6, respectively.…”

“…The model developed by Camaraza et al [14] shows the best Emax index, with 11.5% and 12.9% respectively in Zone 1, and 6. On the contrary, the most unfavorable indicators are obtained with the correlations of Griminson and Zukauskas, which provide 𝐸 max values of 41.4% and 38.5% respectively for Zone 1, increasing to 48.2% and 43.1% in Zone 6.…”

“…An analysis of 783 experimental data sets reported in eight specialized papers on the subject, allowed to develop a dimensionally non-homogeneous expression, which was generated by an integral analysis of residues by cross-jump methods at intervals (Breshnetzov method), which correlates with an average error of ±6.9% in 84.8% percent of the available experimental samples. This equation is given by the following expression [14]:…”

“…where: V0 is the rate of entry of the cooling agent into the tube package, in m/s; ST is the transverse step, in m; SL is the longitudinal step, in m; D is the outer diameter of the tubes + fins, which make up the package, in m; SD is the diagonal step, in m, Table 1 gives the validity parameters of Eq. ( 1), while all the experimental data used in its development and validation are given by Camaraza-Medina et al [14]. The deviation is determined by the following expression:…”

Investigation of air-cooled condenser’s operating parameters in modern thermal power plant

“…The mentioned stochastics of the environment is primarily reflected in the difficulty of wind parameters prediction, the insolation intensities during the day, as well as the deviation of ambient air temperatures from the design values. Particularly for these reasons, a number of researches have been conducted with a goal to find an optimal direction for further improvement of the air-cooled condenser design, [8][9][10][11][12]. Also, the complex phenomena governing the function of air-cooled condensing devices have also been the field of interest of numerous authors, [13][14][15][16].…”