Associate Professor in Mechanical Engineering Department and I/C HOD Mechanical Engineering Department Dr. Vithalrao Vikhe Patil College of Enginring, Ahilyanagar
Experimental Heat Transfer Analysis of Helical Coiled Tubes on the Basis of Variation in Curvature Ratio and Geometry Susheel Madhavrao Magar, Gaurav Kumar Gugliani, Ravindra Rambhau Navthar Journal of Heat and Mass Transfer Research, 2024 The influence of curvature ratio (CR) within helical tubes on secondary flows and subsequent enhancement of heat transfer is well-established. Furthermore, the interaction between the shell fluid and the helical tube is recognized as pivotal in this regard. In this paper, the impact of varying CR and coil geometry on the performance of heat exchangers (HEs) through experimental heat transfer analysis conducted on five distinct coils viz., straight helical (ϴ= 90°), conical (ϴ= 70°,50°,30°), and spiral (ϴ= 0°) configurations have been studied. Moreover, correlations for modified effectiveness are proposed for all HEs. The Reynolds number range chosen for the analysis spans from 3700 to 20000, encompassing laminar and turbulent flow regimes of the coil hot water. The optimal HE is identified based on thermal and hydrodynamic parameters, including hot water temperature difference, effectiveness, modified effectiveness, rate of heat transfer, pressure drops of the coil, shell fluids, and pumping power. Observations reveal that helical cone coil heat exchangers (HCCHEs) demonstrate superior thermal and hydrodynamic characteristics when the fluid flow aligns with increasing CR. Notably, for both laminar and turbulent flows, the highest hot water temperature difference, effectiveness, and rate of heat transfer are observed for ϴ= 30° HCCHE, while the lowest values are attributed to ϴ= 90° HE. Tube side Nusselt numbers, pressure drops, and friction factors show agreement with the predictions of researchers. The analysis reveals that the coil fluid pressure drop is maximal for ϴ =0° HE, whereas the maximum shell fluid pressure drop is encountered for ϴ =90° HE. Furthermore, the highest pumping power per unit heat transfer area for coil and shell fluids are noted for ϴ= 0° HE and ϴ= 90°HE, respectively, while ϴ= 30° HCCHE exhibits comparable performance to the remaining HEs within the specified parameter range, establishing its optimality.
Suggestion of Correlations to Obtain Shell and Tube Side Nusselt Numbers in Coiled Heat Exchangers Magar Susheel Madhavrao, Gugliani Gaurav Kumar, Navthar Ravindra Rambhau Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2024 In coiled tube heat exchangers increase in curvature ratio and effective contact of shell fluid with coil surface led to better thermal characteristics. This work addresses study of thermal performance, shell and tube heat transfer coefficients (ho and hi). Also, mathematical correlations are predicted to obtain shell and tube Nusselt numbers (Nuo and Nui). In the designing of compact coiled heat exchangers consisting of straight helical coil (SHC), conical coil (CC) and spiral coil knowledge of Nuo and Nui is necessary whereas mathematical correlation to calculate Nuo considering variations in shell geometry is not found. Five heat exchangers consisting of three cone coils (angle, ϴ = 30°, 50° and 70°), spiral coil (ϴ = 0°) and SHC (ϴ = 90°) are tested. Using Wilson plot method ho and hi are obtained for wide range of tube side Reynolds numbers (Rei = 3700 - 21000). It is observed that, highest ho is obtained for ϴ = 30°CC with better thermal performance. Lowest ho is obtained for ϴ = 90°SHC. Ratio of height of shell, Hs and diameter of shell, Dso is considered in prediction of single correlation as: Nuo = 16.55.Reo0.55.Pro0.4 *(Hs/Dso)0.096. Comparison with experimental findings shows variation of 0-14%. Similarly two correlations are proposed as: Nui = 0.0512.Rei0.80.Pri0.4.CRave0.18 and Nui = 0.0365.Dei0.815.Pri0.4.CRave-0.3. A fair agreement is found with existing researchers.
RECENT SCHOLAR PUBLICATIONS
Impact of Variable Process Parameters of Magnetic Abrasive Finishing on Surface finish of mild Steel Using a DC current for Electromagnets RE Kalhapure, SM Magar, SK Sheikh, RR Navthar Journal Publication of International Research for Engineering and Management … , 2026 2026.0
Experimental investigation of friction factors and correlation development for shell and conical coil heat exchangers SM Magar, BT Tagad, G Gugliani Heat and Mass Transfer 61 (10), 97 , 2025 2025.0 Citations: 2
Experimental Heat Transfer Analysis of Helical Coiled Tubes on the Basis of Variation in Curvature Ratio and Geometry SM Magar, GK Gugliani, RR Navthar Journal of Heat and Mass Transfer Research 11 (1), 89-108 , 2024 2024.0 Citations: 5
Experimental Investigation Of Thermal Performance Of Helical Cone Coil Heat Exchanger MS Madhavrao, GG Kumar, NR Rambhau International Journal of Advanced Engineering Application 1 (1), 29-52 , 2024 2024.0
Suggestion of correlations to obtain shell and tube side Nusselt numbers in coiled heat exchangers MS Madhavrao, GG Kumar, NR Rambhau J. Adv. Res. Fluid Mech. Therm. Sci. 116 (1), 201-222 , 2024 2024.0 Citations: 2
Studies on deep drawing of steel cups for the variation of yield strength and drawing ratio using FEA SM Magar, PM Ghanegaonkar, MY Khire, AR Kachare MIT International Journal of Mechanical Engineering 3 (1), 1-5 , 2013 2013.0 Citations: 9
Investigations of Deep Drawing of Cylindrical Components: Analytical, Numerical and Experimental approach S Magar, P Ghanegaonkar, G Vikhe LAP LAMBERT Academic Publishing , 2012 2012.0 Citations: 2
The experimental and finite element analysis of deep drawing of cup without flange. KMY Magar S.M. International Journal of Emerging Technologies and Applications in … , 2011 2011.0
Deep drawing of cup shaped steel component: finite element analysis and experimental validation MYK Susheel Madhavrao Magar International Journal on Emerging Technologies, ISSN : 0975-8364 1 (2), 68-72 , 2010 2010.0 Citations: 4
Stiffening Arrangement Optimization For Rectangular Surface Condensers By Parametric Fem Approach SK More, SM Magar International Journal of Innovations in Engineering Research and Technology, 1-3 , 0
Comparative Numerical Analysis of Straight and Conical Coil Heat Exchanger RS Waghmare, HN Deshpande, SY Bhosale, SM Magar, BT Tagad Global Research and Development Journal for Engineering, ISSN, 2455-5703 , 0 Citations: 2
MOST CITED SCHOLAR PUBLICATIONS
Studies on deep drawing of steel cups for the variation of yield strength and drawing ratio using FEA SM Magar, PM Ghanegaonkar, MY Khire, AR Kachare MIT International Journal of Mechanical Engineering 3 (1), 1-5 , 2013 2013.0 Citations: 9
Experimental Heat Transfer Analysis of Helical Coiled Tubes on the Basis of Variation in Curvature Ratio and Geometry SM Magar, GK Gugliani, RR Navthar Journal of Heat and Mass Transfer Research 11 (1), 89-108 , 2024 2024.0 Citations: 5
Deep drawing of cup shaped steel component: finite element analysis and experimental validation MYK Susheel Madhavrao Magar International Journal on Emerging Technologies, ISSN : 0975-8364 1 (2), 68-72 , 2010 2010.0 Citations: 4
Experimental investigation of friction factors and correlation development for shell and conical coil heat exchangers SM Magar, BT Tagad, G Gugliani Heat and Mass Transfer 61 (10), 97 , 2025 2025.0 Citations: 2
Suggestion of correlations to obtain shell and tube side Nusselt numbers in coiled heat exchangers MS Madhavrao, GG Kumar, NR Rambhau J. Adv. Res. Fluid Mech. Therm. Sci. 116 (1), 201-222 , 2024 2024.0 Citations: 2
Investigations of Deep Drawing of Cylindrical Components: Analytical, Numerical and Experimental approach S Magar, P Ghanegaonkar, G Vikhe LAP LAMBERT Academic Publishing , 2012 2012.0 Citations: 2
Comparative Numerical Analysis of Straight and Conical Coil Heat Exchanger RS Waghmare, HN Deshpande, SY Bhosale, SM Magar, BT Tagad Global Research and Development Journal for Engineering, ISSN, 2455-5703 , 0 Citations: 2
Impact of Variable Process Parameters of Magnetic Abrasive Finishing on Surface finish of mild Steel Using a DC current for Electromagnets RE Kalhapure, SM Magar, SK Sheikh, RR Navthar Journal Publication of International Research for Engineering and Management … , 2026 2026.0
Experimental Investigation Of Thermal Performance Of Helical Cone Coil Heat Exchanger MS Madhavrao, GG Kumar, NR Rambhau International Journal of Advanced Engineering Application 1 (1), 29-52 , 2024 2024.0
The experimental and finite element analysis of deep drawing of cup without flange. KMY Magar S.M. International Journal of Emerging Technologies and Applications in … , 2011 2011.0
Stiffening Arrangement Optimization For Rectangular Surface Condensers By Parametric Fem Approach SK More, SM Magar International Journal of Innovations in Engineering Research and Technology, 1-3 , 0