Pressure drop prediction for R407C fluid during flow evaporation in horizontal pipes using Kalman Filter

• Published in: International journal of refrigeration Vol. 168; pp. 149 - 158
• Main Authors: de Souza, Gabriel Gonçalves Lemes, Duarte, Willian Moreira, de Oliveira, Raphael Nunes, Maia, Antônio Augusto Torres
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2024
• Subjects: Chute de pression; Filtre de Kalman; Horizontal pipes; Hydrofluorocarbon refrigerant; Kalman filter; Mini tube; Pressure drop; R22; R407C; Tuyaux horizontaux; Two-phase flow; Écoulement diphasique; R407C; Mini-tube; Kalman filter; Mini tube; Écoulement diphasique; Chute de pression; R22; Pressure drop; Two-phase flow; Filtre de Kalman; Hydrofluorocarbon refrigerant; Tuyaux horizontaux; Horizontal pipes
• ISSN: 0140-7007
• DOI: 10.1016/j.ijrefrig.2024.07.027

•One-dimensional Kalman Filter was used to reduce pressure drop estimation errors.•Kalman Filter initialization equation were developed based on pressure drop parameters.•Significant improvements were observed, particularly for mini tubes.•Kalman Filter approach MARD decreased from 62.90 to 12.12 for mini tubes. The estimation of pressure drop in systems involving two-phase fluids holds a substantial influence over system design, energy efficiency, heat transfer dynamics, and the overall system performance. Existing correlations in the current literature exhibit considerable errors, primarily attributable to the diverse characteristics of flow patterns inside the pipe. This work presents a discussion on the pressure drop of the R-407C fluid in horizontal pipes during two-phase flow, along with the application of the Kalman Filter to improve the estimations produced by well-known correlations. The initialization data used were obtained through equations created based on experimental data and considering the influence that diameter, mass velocity, and saturation pressure have on the pressure drop. The correlations used as a basis for the calculations were selected from the literature, considering the lowest percentage error observed in the pressure drop estimation. Experimental data of pressure drop where compared with the results the obtained by using the correlation alone and in combination with a Kalman Filter. For tubes with a diameter greater than 1.5 mm, applying the correlation together with the Kalman Filter resulted in a Mean Absolute Relative Deviation (MARD) of 15.71, whereas using the correlation alone yielded a MARD of 28.26. For tubes with diameters of 1.5 mm or less, the MARD values were 12.12 and 62.90, for the combination of correlation and the Kalman Filter and for the correlation alone, respectively. These results underscore the viability of the Kalman Filter as an effective tool for improving the accuracy of pressure drop calculations in horizontal tubes.