The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform
Mohammed Ahmed Yousif Adam - One of the best experts on this subject based on the ideXlab platform.
-
Effect of tube inclination angle on the Thermal and fluid dynamic performance of flat tube heat exchanger
2017Co-Authors: Mohammed Ahmed Yousif AdamAbstract:At the present time, the performance of finned and flat tube heat exchangers (HEs) has become a very important issue in the Thermal industrial sector. Finned-and-flat tube heat exchangers have gained great interest from many researchers due to their role in any Thermal Engineering System. Some geometrical and process parameters such as fin spacing, tube spacing, tube inclination angle, etc. affects the performance of fin-and flat tube heat exchangers. Significant number of research have been done to study the effect of such geometrical and process parameters. However, the effect of flat tube inclination angle on the Thermal-hydraulic performance of fin-and-tube HE is not fully examined. Thus, the aim of this study was to investigate the effect of flat tube inclination angle, air velocity and tube configuration on the Thermal and flow characteristics of compact fin-and-flat tube heat exchangers. A series of experimental and numerical investigations were carried out to evaluate the influence of the aforementioned parameters on the Thermal-hydraulic performance between the tube bundles. Moreover, Response Surface Methodology (RSM) was used to determine the optimum parameter condition for the fin-and–tube HE. The range of the parameters considered in the study were tube inclination angle from 0˚ to 150˚, inlet air flow velocity from 1.8 to 3.8 m/s and tube configuration (inline and staggered). For the experiments, the wind tunnel available at the Faculty of Mechanical Engineering, UMP was used. The wind tunnel was equipped with a blower of capacity 50 W, flow straightener, test section and measuring sensors. Twelve plate fin and nine flat tube heat exchangers test sections were designed and manufactured at various inclination angles and configurations. Temperature, velocity, and pressure measurements were recorded at various positions in the test section as well as before and after the test section. For the numerical analysis, the CFD commercial software called ANSYS FLUENT-15 was used to solve the Navier-Stoke and energy equations together with proper turbulent equations. The parameters are similar to the experimental investigation. The experiment and numerical analysis used Nusselt number, pressure drop, and area goodness factor to evaluate the Thermal-hydraulic performance of fin-and-flat tube heat exchangers. The major findings showed that flat tube inclination angle has significant impact on the heat transfer enhancement. However, the results from both experimental and numerical analysis revealed that increasing the tube inclination angle from 0˚ to 90˚ augments the convective heat transfer coefficient. While 120˚ and 150˚ provide Thermal performance close to 60˚ and 30˚, respectively. The average deviations of Nusselt number between experimental and numerical results were 5.42% and 4.44% for inline and staggered configurations respectively. Moreover, due to the air flow blockage caused by inclining the tube angle, the pressure drop increases dramatically for all cases studied. From all acquired results, the best Thermal performance occurred at 0˚, while 90˚ provided the minimum Thermal performance. Therefore, inclining the tube is beneficial for enhancing the heat transfer performance but is not beneficial in term of pressure drop as it requires higher pumping power. The developed correlations from the RSM can predict experimental data with average deviation of 2.78% for Nu for both configurations. Moreover, it can predict the numerical data with average deviation of 0.554% and 0.92% for inline and staggered configuration, respectively. The optimum parameters are found to be with high air velocity and low tube inclination angle which provide maximum heat transfer enhancement and low-pressure drop penalty. Thus, it is recommended for the design of fin-and-flat tube HEs.
L. B. Korelshtein - One of the best experts on this subject based on the ideXlab platform.
-
Approximate Mathematical Model of Heat Exchange in a Complex Thermal Engineering System of Several Product Pipelines Carrying a Motionless IsoThermal Product within a Single Insulating Jacket
Doklady Chemistry, 2018Co-Authors: V. P. Meshalkin, T. A. Kokhov, T. N. Gartman, L. B. KorelshteinAbstract:An approximate mathematical model was developed to describe the heat exchange in a complex Thermal Engineering System of several parallel product pipelines carrying an motionless isoThermal product within a single insulating jacket. The model is distinguished by using a simplified mathematical model of the steady-state heat conduction on a circle (motionless product) and in an annulus (product pipeline wall) under the Robin boundary conditions using various “approximating” effective heat-transfer coefficients in different parts of the boundary of a heated product pipeline carrying the isoThermal product with the air space and the insulation.
Jatin Patel - One of the best experts on this subject based on the ideXlab platform.
-
Application of Nanofluids in Solar Energy
2015Co-Authors: Ruchik Thaker, Jatin PatelAbstract:Nanofluids are skillfully prepared colloidal suspensions of nanoparticles (which is of size 1–100 nm) in a base fluid; is a relatively new field, which is not more than two decades old. The main idea of this paper is to know about the applications of nanofluids in solar Thermal Engineering System. The shortage of conventional sources and environmental problems motivated the researchers to use non-conventional energy sources such as solar energy and others. Thus it is essential to improve the efficiency and performance of the solar Systems. It is found that nanofluids have higher Thermal conductivity which is temperature-dependent at very low particle concentrations than the respective conventional fluids. This can be observed as one of the very important parameters to upgrade the performances of many applications of nanofluids. Challenges of nanofluids are also considered in this paper. Some potential future works are also proposed to use the nanofluids in different solar Thermal Systems. Keywords: Nanofluids, solar energy, efficiency, challenges
Vasko N. Šarevski - One of the best experts on this subject based on the ideXlab platform.
-
Application of Ejector Thermocompression in Industrial Thermal Engineering Systems
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:Applications of ejector thermocompression in industrial concentrators, as well as in industrial Thermal Systems, such as steam ejector vacuum Systems, water two-phase ejector vacuum Systems, and industrial closed steam-condensate Thermal Engineering Systems, are investigated. Performance characteristics of multistage steam ejector vacuum Systems with direct flash intercoolers are analyzed and an optimizing procedure is proposed. An analysis of the characteristics of water two-phase ejector vacuum Systems is given. A novel closed steam–condensate Thermal Engineering System with ejector thermocompression is discussed and technical and operating advantages in comparison with traditional Systems is given. With optimal application of ejector thermocompression, the waste heat of the concentrators can be utilized and thermo-transformed heat at higher temperature levels can be used for realization of the concentrating processes. A sodium hydroxide industrial concentrator and an experimental grape vacuum concentrator with ejector thermocompression are investigated and results concerning energy efficiency improvement are discussed.
S. V. Panchenko - One of the best experts on this subject based on the ideXlab platform.
-
Automated Analysis of the Energy-Saving Potential in a Thermal Engineering System for Phosphorus Production
Theoretical Foundations of Chemical Engineering, 2004Co-Authors: S. V. PanchenkoAbstract:Automated evaluation of the energy efficiency of chemical Engineering Systems is considered by the example of phosphorus production. Possible phosphorus production flowsheet solutions are obtained, which allow one to increase the energy and exergy efficiency of the System using specially developed software. Flowsheets of the System are produced by topological synthesis methods. It is shown that an integrated approach to energy saving in production Systems can ensure the optimal use of underutilized energy resources in technological processes.