Experimental investigation of axial finned tube evaporator thermal distillation system using for die

Abstract

Keywords: Axial Finned Tube Evaporator; Exhaust Gas; Thermal Distillation Unit; Waste Heat Recovery

Introduction

In today’s world, technological breakthroughs have improved the quality of life for everyone. These advancements have raised the global energy demand, resulting in an increase in energy prices [1]. The net global energy consumption has reached to 132 PW h, out of which 72 % of energy is lost in ecosystem as waste energy [2]. Nearly three-quarters of waste heat is attributed to exhaust and effluent losses that can be retrieved, while remaining onefourth is unrecoverable [3].

Waste heat energy also contributed to global warming and had an adverse impact on our ecosystem. To deal with current energy crises, global warming and hike in energy prices, scientific community is focused to hunt novel pathways to improve energy efficiency [4]. Over the last decades, policymakers have implemented several rules and regulations to reduce or eliminate greenhouse gases (GHGs) [5]. Such initiatives have aided rapid development in this subject. One of the cost effective and convenient ways to improve energy efficiency is to recover waste heat energy. Consequently, the recovery of dissipated heat energy has

*Corresponding author. *E-mail address: satyendrakumar79@gmail.com This paper was recommended for publication in revised form by Regional Editor Md Hasanuzzaman Published by Yıldız Technical University Press, İstanbul, Turkey Copyright 2021, Yıldız Technical University. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

emerged as one of the hottest research topics. Farhat et al. [6] studied on waste heat recovery methodology and applications for industrial, residential and internal combustion engine waste thermal energy. It was recommended that the optimized waste recovery system should be used for better efficiency and effectiveness of systems. Varshil and Deshmukh [7] also reviewed the recovery of lost energy from compression ignition engines. It was concluded that exergy efficiency of single loop and combined loop waste heat recovery system were 35% and 46%, respectively. Hussein et al. [8-12] conducted theoretical, experimental and numerical studies on nano-fluid for energy applications. As a result, the efficiency of renewable energy systems was improved by using nanotechnology. Hussein et al. [13-14] also investigated the performance of double filled glazing unit by using phase change material (PCM). It was observed that the thermal energy storage capacity varies with different thermos-physical properties of PCM. Benabderrahmane et al. [15] presented central corrugated insert in parabolic trough receiver. It was found that average tube side Nusselt number and friction factor was enhanced by 3.7 and 1.8 times relative to smooth absorber, respectively. Ghodbane et al. [16] developed a solar-driven ejector air conditioning system. It was found that the coefficient of performance of ejector air conditioning subsystem was 60.66%. Research in field of waste heat recovery (WHR) has been accelerated, particularly with regard to fossil fuel systems in numerous industries including aluminum industry, ceramic industry, desalination, and many more [17–20]. WHR units not only reduces the fuel consumption but also prevents adverse environmental impacts including GHGs emission and carbon footprints [21,22]. There are some important strategies have been proposed for WHR such as heat-to-heat, heat-to-work and heat-to-power [23]. Efficiency of WHR is maximum in the case of heat-to-heat strategy. This is attributed to the increase in thermodynamic energy losses when converting heat-to-heat, then to work and finally, to power. Among these strategies, heat-to-heat WHR strategy is the easiest way to recover heat with the help of heat exchangers [24]. The efficiency of WHR also depends on variety of situations including continuous or discontinuous supply, temperature, the mode of heat transfer, type and composition of fuel, type of heat exchanger and distance between source and sink [3]. In spite of the difficulties, there is a tremendous potential in WHR units to meet emergent energy demand. Recently, WHR units are also used to power desalination units [25]. Such approach not only improve the energy efficiency but also resolve the global problem of fresh water scarcity. Feria-Diaz et al. [26] studied on an optimized thermal desalination system to hybridized with the existing desalination system. The hybridized desalination system was operated with the help of renewable energy. As a result, a reduction in dependences on electrical and combustion energy reduces. Dumka and Mishra [27] performed experimentation to recover the coolant waste thermal energy

with the help of double slop long still (DSLS). Recovered thermal energy was used for water distillation. It was found that evaporative heat transfer coefficient reduces by approximately 64.40% from entrance to exit of DSLS. Morciano and co-workers [28] developed waste heat driven passive membrane desalination system. The waste energy was retrieved from ICE fueled with diesel. The results revealed that ~ 2.61 L/m2h fresh water was produced from the seawater. The type of heat exchanger plays a crucial role on the overall efficiency of waste heat driven desalination system. Sertkaya and Sari [29] performed an experimental investigation on longitudinal finned and radial finned tube heat exchanger for natural heat energy transfer. Heat exchanger performance was estimated on different inclination of the tube. It was found that finned and inclined heat exchanger performed better than smooth tube. G. Krishnayatra and co-workers [30] also investigated the performance of axial finned tube heat exchanger with various geometric parameters. It was concluded that effectiveness of the fin increases with increasing fin spacing and fin thickness. These studies revealed that the axial finned heat exchangers are suitable WHR units. Moreover, impact of heat exchanger type on efficiency of waste heat driven distillation unit is scarce in literature. Therefore, it is crucial to conduct a systematic study to investigate the role of axial finned tube evaporator on distillation productivity. In the present study, four different types of heat exchangers were used to examine performance of waste heat driven distillation unit. One of these heat exchangers was smooth copper tube and other three are axial finned copper tubes with two, three and four fins. The impact of engine load and the number of axial fins on the distillation productivity was also determined.

Experimental Details

A 7 horse power (HP) single cylinder water cooled compression ignition engine was used in the present investigation. A dynamometer was connected to the engine through a shaft to measure the engine load precisely. Digital anemometer was installed at the air intake port of the engine to estimate the air consumption in terms of velocity. The diesel container was placed at appropriate elevation and

connected to the engine through burette. The consumption of fuel was measured through burette. Technical detail of engine is presented in Table 1. Shell and tube evaporators were used to retrieve low grade waste thermal energy of exhaust gas. Shell and tube of evaporators were made of mild steel and copper materials, respectively. Total four evaporators were used in the present study. One evaporator was made of smooth copper tube. Three other evaporators were modified with longitudinal finned (two, three and four axial fins) on the tube surface. Thickness and height of the axial fin was 2 and 5 mm, respectively. Smooth and modified tube of evaporators were arrayed at the bottommost of the shell; so that, it can properly submerge in water. Coolant fluid (water) was allowed to pass through shell side, while exhaust gas through tube side as working fluids. Figure 1 presents the horizontal submerge tubes with different modified tube surface. A shell and two pass U-tube condenser were installed and connected through tube to evaporator. Shell and tube of condenser were made of mild steel and copper, respectively. Dimension of boilers and condenser used in the present work are tabulated in Table 2.

Methodology

Experimental setup was equipped with thermocouples, pressure gauge, rotameter and tachometer. K- type of thermocouples were positioned at appropriate places to measure and record temperature. All thermocouples have been calibrated with the help of thermal bath and multimeter. Pressure gauge was installed at the center of the boiler to measure the steam pressure. Used pressure gauge was calibrated by pressure hand pump and digital pressure gauge. Two separate flowmeters (rotameters) were mounted to determine coolant fluid flow rate in boiler and condenser. Each rotameter was standardized by glass beaker. Diesel fueled ICE speed was measured in RPM through a digital non-contact tachometer. The engine speed was calibrated with non-contact tachometer. Schematic view and photograph of the test unit is presented in Figure 2-3. The experiment was initiated by starting an engine manually and then, the electrical load was applied. Initially engine exhaust was discharged into the surrounding environment by opening valve-1 and closing valve-2. This was done to avoid flue gas stream dust accumulation on surface of evaporator tubes. Later, valve-1 was closed and valve-2 was opened to flow flue gas through copper tubes of the

Figure 1. Representation of (a) smooth tube, (b) two axial fin tube, (c) three axial fin tube and (d) four axial fin tube evaporators (boilers).

Table 2. Evaporator and condenser dimension details Parameters

boiler, which were submerged in water and released to atmosphere. Feed water was supplied in evaporator from water tank-1 at 30 °C, and flow rate was fixed at 2.5 LPH by Rotameter-1. Exhaust gas waste thermal energy was extracted by water and used for the conversion water into vapors. The saturated steam was accumulated on the surface of boiler coolant fluid and allowed to flow out from the evaporator. Afterwards, the steam was supplied to a condenser copper tube at one end. On the shell side, coolant fluid was supplied to condenser from tank-2 and mass flow rate was regulated through flowmeter-2. Shell side condenser water was heated by recovered heat from the tube side vapors. Later, vapors were allowed to condensed in a condenser copper tube. Finally, potable water (distillated yield) was obtained from other end of the condenser copper tube. Potable water was stored into potable water tank. The complete procedure was repeated for 100 minutes to each load. The total yield of distilled water was calculated by measuring glass beaker. Above experimental procedure was used for each type of boiler and at different engine loads 25, 50 and 75 %. Data Reduction Some assumptions were considered throughout experimentation work which are listed below: (i) Flue gas is supposed as ideal gas. (ii) The Specific thermal capacity of flue gas at constant pressure (Cpf ) is temperature dependent. (iii) Potential and kinetic energies of combustion gas do not change significantly. (iv) Neglecting thermal energy losses to the environment. (v) Conduction in longitudinal direction of the tubes is insignificant. (vi) All parameters are measured after achieving the steady state. Energy analysis of evaporator Heat energy retrieved from the combustion gas was calculated at considered load condition by applying the equation:

A quantity of flue gas is discharged by the diesel engine. (4) Heat energy enters the boiler tube =

The required heat energy can be calculated by using equation [33]: (6) According to low of energy balance, heat lost by combustion gas is equal to heat required for evaporation of water. So, equation (1) is equal to equation (6). (7) Energy analysis of condenser Heat carried by condensed water is (8) Heat gain by coolant fluid is (9) The condenser was designed at an evaporation rate of water in the boiler. Heat energy is loosed by water steam in the condenser to condensed the steam into distilled water. Liberated heat is used for heat up cooling water, and remaining thermal energy was also carried by distilled water. Both fluids of condenser have been used as useful products. According to conservation of energy, energy loss is equal to energy gain. So the equation is [33]: (10) Thermal energy loosed by water vapor in condenser to convert into condensed water =

Specific thermal capacity of combustion gas can be written as [31]: (2) By using heat capacity of flue gas, the formula for change in enthalpy of combustion gas was modified by Hatami and co-authors [32]. Finally, it is possible to write the modified equation as (3)

(12) Net energy efficiency of thermal distillation system is: (13) Exergy analysis of evaporator Change of exergy of flue gas is: (14)

The mathematical relation to the change in the entropy of the combustion gas was modified by Hatami and co-authors [32] using specific heat of flue gas. Final equation can be written as (15) By putting the value of and (15) in equation (14)

Boiler and condenser tube Curve and cross- ± 0.8330 sectional area Combustion gas flow rate

uncertainty (WR) is necessary. In this study, uncertainties have been calculated by following equation (25) which is given below [34]. The value of uncertainty in all calculated quantities is arranged in Table 3.

Results And Discussion

(20) Exergy analysis of condenser Condensed water exergy at exit of condenser (21) Coolant fluid exergy at exit of condenser (22) (23) Net exergy efficiency of distillation system is: (24) Uncertainty Analysis In experimentation, some errors may be involved due to parameter calculation through instrument and human observation. The error reduces accuracy of obtained results. Therefore, calculation of error in calculated parameters as

Experimental Validation Figure 4 (a-c) are showing the comparison of the temperature at the inlets and outlets of the evaporators (smooth tube and two axial finned tube) with the literature at 25, 50 and 75 % engine load. The comparison revealed that the experimental results are in agreement with published work [33]. The temperature and time curve characteristics remain the same when compared to the reported literature. However, the magnitude of the temperature was different as found in Figure 4. The difference is attributed to the power of engine used in this investigation. It is clear that the difference in temperature at inlets and outlets of the boilers increased with increase in the ICE load. This resulted in high recovery of waste thermal energy and enhancement in the production yield of potable water. Net Recovered Energy and Exergy The net retrieved energy and exergy was determined for smooth tube as well as axial finned (two, three and four axials finned) tube evaporators. Figure 5 – 6 presented the value of net retrieved energy and exergy of all four evaporators at different load conditions (25, 50 and 75 % engine load). At higher engine load, the consumption of fuel by ICE is higher to meet the power requirement. This led increment in temperature and flow rate of combustion gas at entrance of evaporators. Consequently, net thermal energy extraction rate improved by ~ 95.046 % at 75 % engine load compared to at 25% engine load in the case

of smooth tube boiler. Moreover, heat transfer surface area increased by increasing in number of axial fins on boiler tube. Hence, the energy extraction rate improved in four axial finned tube evaporators. It was clear that the thermal energy extracted with four, three and two axial finned tube evaporators were more than that of smooth tube evaporator by about 26.823 - 45.513 %, 12.202 - 21.979 % and 5.084 13.930 %, respectively. Figure 6 demonstrated the variation

Figure 5. Variation of net extracted energy with load for smooth tube evaporator, two, three and four longitudinal finned tube evaporators.

Figure 4. Temperature and time curve for different loads (a) 25% (b) 50% (c) 75%.

Figure 6. Variation of net extracted exergy with load for smooth tube evaporator, two, three and four longitudinal finned tube evaporators.

of net extracted exergy with respect to engine load for four different types of evaporators. As engine load increased, so, the thermal availability of exhaust gas also increased. The recovery of waste heat exergy increased with increase in engine load for all the considered cases. The net recovered exergy in the case of two and four finned tube evaporates at 25 % and 75 % load were 1.442 – 7.614 W and 7.713 – 25.203 W higher than that of plane tube, respectively. The energy transfer area per unit length increased by increasing the number of fins on evaporating surface. Therefore, it was also found that the retrieved exergy improved with increase in number of axial fins in boiler tube surface. Furthermore, the highest extracted exergy was approximately 80.582 W in the case of four finned tube boiler at 75% load. Net Efficiency Figure 7 presented the curves of net energy efficiency for various types of evaporators at 25, 50 and 75 % engine load. With increase in engine load, waste energy disposal also increased at the entrance of evaporators. The recovered waste heat energy act as driving force for the thermal distillation unit. The net energy efficiency for the smooth tube boiler was 21.075 % and 27.653 % at 25 % and 75 % engine load, respectively. It was found that the net energy efficiency improved when surface area of heat transfer increased. Maximum net energy efficiency (40.239 %) was obtained for four axial finned boiler at maximum considered engine load. Furthermore, net exergy efficiency of thermal distillation unit with different evaporators at 25, 50 and 75 % engine load is demonstrated in Figure 8. During the study, it was observed that an increase in temperature of the flue gas raised the exergy destruction. As results, net exergy efficiency reduced with increase in engine load. In

Figure 7. Net energy efficiency and load curve for smooth tube evaporator, two, three and four longitudinal finned tube evaporators.

addition, number of fins on evaporator tube surface also effects the efficiency of the thermal distillation unit. The, net exergy efficiency for smooth tube evaporator was found to be 5.411 % and 4.518% at 25 % and 75 % engine load, respectively. The highest efficiency (~ 6.863 %) was observed for the four finned tube boiler at 25 % load. This clearly indicated that axial finned tube evaporators are better than smooth tube evaporators.

Figure 8. Net exergy efficiency and load bar chart for smooth tube evaporator, two, three and four longitudinal finned tube evaporators.

Figure 9. Distillated yield and load bar chart for smooth tube evaporator, two, three and four longitudinal finned tube evaporators.

Distillation Yield Distillated yield vs. load bar graph for all considered evaporators is illustrated in Figure 9. The water evaporation rate improved in evaporator by increasing in engine load. This resulted in increment of water vapor flow rate though condenser tube. The water flow rate in condenser shell side was also increased to condense the increased amount of vapor as distillated yield. Distillated yield was found to be 0.83 liter/hour at 25% load and 1.6 liter/hour at 75% load in smooth tube evaporator. Moreover, heat transfer rate enhanced with increasing number of fins on evaporating surface. More water molecules received sufficient kinetic energy for conversion into vapor phase. As a result, the evaporation rate of water in evaporator improves by increasing number of axial fins on boiler tube surface. Therefore, distillated yield improves with longitudinal fin tube evaporator as compared to smooth tube evaporator. Distillated yield was maximum (2.35 liter/hour at 75% load) for four longitudinal fin tube evaporator.

Conclusion

A thermal distillation system was used to retrieve the waste heat energy from flue gas. The impact of boiler type and considered load on the efficiency of thermal distillation unit was examined. Using all considered types of evaporators, including one smooth, the remaining ones were axial finned tubes with two, three, and four axial fins. A shell and U-tube condenser were used in the study. Thermal distillation system was driven by the recover thermal energy of flue gas from 7 hp diesel engine generator at 25, 50 and 75 % engine load. Net retrieved thermal energy and exergy, Net energy and exergy efficiency, distillated yield was obtained. The following conclusions can be drawn from the present investigation.

1. The net extracted thermal energy was found to be

45.513 % higher for four finned tube boiler as compared to smooth tube boiler at 75 % engine load.

3. The net energy efficiency was found to be 40.239 % at

75 % load, and net exergy efficiency was 6.863 % at 25 % load for four axial finned tube evaporator.

4. Finally, the distillation yield of ~ 2.35 liter/hour was

achieved in case of four finned tube evaporator. An axial finned tube evaporator for thermal distillation has opened up new avenues for the development of a more efficient thermal distillation system. Such distillation system can be used at construction sites, restaurants, hospitals, community halls etc. to supply potable water without consuming power from external sources.

Latent heat, kJ/kg Mass flow rate, kg/s Pressure, bar Rate of thermal energy, kJ/s Universal gas constant, kJ/kg-K Entropy, kJ/kg-K Entropy changes, kJ/kg-K Temperature, K Change in temperature, K

Greek Symbols ∅ Exergy, kJ/kg Δ∅ Change of exergy, kJ/s ƞI Net energy efficiency ƞII Net exergy efficiency

Subscripts c Condenser, Coolant fluid, Condensate e Evaporator (Boiler) f Flue gas i Inlet o Outlet, Surrounding condition req Required s Saturation v Vapor w water

Originality Of The Scientific Article

This study is devoted to recovering waste energy from the combustion gas of a compression ignition engine at different loads using thermal distillation system. Smooth and axial finned tube evaporators have been used during experimentation. Finally, the performance of the thermal distillation unit has been examined.

Authorship Contributions Statement

Satyendra Kumar: Conceptualization, Performing experimentation, Formal analysis, Writing- original draft. Prakash Chandra: Arranging resources, Supervising experimentation, Editing original draft.

Data Availability Statement

The authors confirm that the data that supports the findings of this study are available within the article. Raw data that support the finding of this study are available from the corresponding author, upon reasonable request.

Conflict Of Interest

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Specific heat capacity, kJ/kg-K Enthalpy, kJ/kg Change of energy, kJ/kg

Ethics

There are no ethical issues with the publication of this manuscript.

References

1. [1] Jouhara H, Khordehgah N, Almahmoud S, Delpech B, Chauhan A, Tassou SA. Waste heat recovery technologies and applications. Therm Sci Eng Prog 2018;6:268–289. [CrossRef]
2. [2] Forman C, Muritala IK, Pardemann R, Meyer B. Estimating the global waste heat potential. Renew Sustain Energy Rev 2016;57:1568–1579. [CrossRef]
3. [3] Olabi AG, Elsaid K, Sayed ET, Mahmoud MS, Wilberforce T, Hassiba RJ, et al. Application of nanofluids for enhanced waste heat recovery: A review. Nano Energy 2021;84:105871. [CrossRef]
4. [4] Klemeš JJ, Kravanja Z. Forty years of heat integration: Pinch Analysis (PA) and Mathematical Programming (MP). Curr Opin Chem Eng 2013;2:461–474. [CrossRef]
5. [5] Moustafa HM, Nassar MM, Abdelkareem MA, Mahmoud MS, Obaid M. Synthesis of single and bimetallic oxide-doped rGO as a possible electrode for capacitive deionization. J Appl Electrochem 2020;50:745–755. [CrossRef]
6. [6] Farhat O, Faraj J, Hachem F, Castelain C, Khaled M. A recent review on waste heat recovery methodology and applications: Comprehensive review, critical analysis and potential recommendations. Clean Engineer Technol 2022;6:100387. [CrossRef]
7. [7] Varshil P, Deshmukh D. A comprehensive review of waste heat recovery from a diesel engine using organic rankine cycle. Energy Reports 2021;7:3951–3970. [CrossRef]
8. [8] Hussein AK. Applications of nanotechnology in renewable energies-A comprehensive overview and understanding. Renew Sustain Energy Rev 2015;42:460–476. [CrossRef]
9. [9] Hussein AK, Walunj AA, Kolsi L. Applications of nanotechnology to enhance the performance of the direct absorption solar collectors. J Therm Engineer 2016;2:529–540. [CrossRef]
10. [10] Hussein AK. Applications of nanotechnology to improve the performance of solar collectors – Recent advances and overview. Renew Sustain Energy Rev 2016;62:767–792. [CrossRef]
11. [11] Hussein AK, Li D, Kolsi L, Kata S, Sahoo B. A review of nanofluid role to improve the performance of the heat pipe solar collectors. Energy Procedia 2017;109:417–424. [CrossRef]
12. [12] Rostami S, Sepehrirad M, Dezfulizadeh A, Hussein AK, Goldanlou AS, Shadloo MS. Exergy optimization of a solar collector in flat plate shape equipped with elliptical pipes filled with turbulent nanofluid flow: a study for thermal management. Water 2020;12:2294–2310. [CrossRef]
13. [13] Li D, Li Z, Zheng Y, Liu C, Hussein AK, Liu X. Thermal performance of a PCM-filled double-glazing unit with different thermophysical parameters of PCM. Solar Energy 2016;133:207–220. [CrossRef]
14. [14] Liu C, Wu Y, Li D, Ma T, Hussein AK, Zhou Y. Investigation of thermal and optical performance of a phase change material filled double-glazing unit. J Build Physics 2018;42:99–119. [CrossRef]
15. [15] Benabderrahmane A, Benazza A, Hussein AK. Heat transfer enhancement analysis of tube receiver for parabolic trough solar collector with central corrugated insert. J Heat Transf 2020;142:062001-1–8. [CrossRef]
16. [16] Ghodbane M, Boumeddane B, Hussein AK. Performance analysis of a solar-driven ejector air conditioning system under EL-OUED climatic conditions, Algeria. J Therm Engineer 2021;7:172–189. [CrossRef]
17. [17] Brough D, Jouhara H. The aluminium industry: A review on state-of-the-art technologies, environmental impacts and possibilities for waste heat recovery. Int J Thermofluids 2020;1–2:100007. [CrossRef]
18. [18] Delpech B, Milani M, Montorsi L, Boscardin D, Chauhan A, Almahmoud S, et al. Energy efficiency enhancement and waste heat recovery in industrial processes by means of the heat pipe technology: Case of the ceramic industry. Energy 2018;158:656–665. [CrossRef]
19. [19] Elsaid K, Taha Sayed E, Yousef BAA, Kamal Hussien Rabaia M, Ali Abdelkareem M, Olabi AG. Recent progress on the utilization of waste heat for desalination: A review. Energy Conver Manage 2020;221:113105. [CrossRef]
20. [20] Huang F, Zheng J, Baleynaud JM, Lu J. Heat recovery potentials and technologies in industrial zones. J Energy Inst 2017;90:951–961. [CrossRef]
21. [21] Yang MH, Yeh RH. Thermo-economic optimization of an organic Rankine cycle system for large marine diesel engine waste heat recovery. Energy 2015;82:256–268. [CrossRef]
22. [22] Liu Y, Chen Y, Ming J, Chen L, Shu C, Qu T, et al. Harvesting waste heat energy by promoting H+-ion concentration difference with a fuel cell structure. Nano Energy 2019;57:101–107. [CrossRef]
23. [23] Egilegor B, Jouhara H, Zuazua J, Al-Mansour F, Plesnik K, Montorsi L, et al. ETEKINA: Analysis of the potential for waste heat recovery in three sectors: Aluminium low pressure die casting, steel sector and ceramic tiles manufacturing sector. Int J Thermofluids 2020;1–2:100002. [CrossRef]
24. [24] Erguvan M, MacPhee DW. Second law optimization of heat exchangers in waste heat recovery. Int J Energy Res 2019;43:5714–5734. [CrossRef]
25. [25] Olabi AG, Elsaid K, Rabaia MKH, Askalany AA, Abdelkareem MA. Waste heat-driven desalination systems: Perspective. Energy 2020;209:118373. [CrossRef]
26. [26] Feria-Diaz J, Lopez-Mendez M, Rodriguez-Miranda J, Sandoval-Herazo L, Correa-Mahecha F. Commercial thermal technologies for desalination of water from renewable energies: A state of the art review. Processes 2021;9:262. [CrossRef]
27. [27] Dumka P, Mishra DR. Experimental investigation and thermal analysis of a double slope long still: Study of heat and mass transfer. Int J Ambient Energy 2020;43:1–15. [CrossRef]
28. [28] Morciano M, Fasano M, Bergamasco L, Albiero A, Lo Curzio M, Asinari P, et al. Sustainable freshwater production using passive membrane distillation and waste heat recovery from portable generator sets. Appl Energy 2020;258:114086. [CrossRef]
29. [29] Sertkaya AA, Sarı S. Experimental investigation of heat transfer depending on inclination angle of unfinned, axial finned and radial finned heat exchangers. Int J Heat Mass Transf 2021;165:120704. [CrossRef]
30. [30] Krishnayatra G, Tokas S, Kumar R. Numerical heat transfer analysis & predicting thermal performance of fins for a novel heat exchanger using machine learning. Case Stud Therm Eng 2020;21:100706. [CrossRef]
31. [31] Hatami M, Jafaryar M, Ganji DD, Gorji-Bandpy M. Optimization of finned-tube heat exchangers for diesel exhaust waste heat recovery using CFD and CCD techniques. Int Comm Heat Mass Transf 2014; 57: 254–263. [CrossRef]
32. [32] Hatami M, Ganji DD, Gorji-Bandpy M. Experimental and numerical analysis of the optimized finned-tube heat exchanger for OM314 diesel exhaust exergy recovery. Energy Conver Manage 2015;97:26–41. [CrossRef]
33. [33] Maheswari KS, Kalidasa Murugavel K, Esakkimuthu G. Thermal desalination using diesel engine exhaust waste heat - an experimental analysis. Desalination 2015;358:94–100. [CrossRef]
34. [34] Holman JP. Experimental Methods for Engineers. 7th ed. New York: McGraw Hill; 2012.

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