Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 237 https://internationalpubls.com Numerical Analysis of Thermal Performance in Solar Thermal Collector System with Artificial Roughness 1Arbind Kumar Amar, 2 Dr Mani Kant Paswan, 3 Dr. Ajay Giri 1Associate professor in Mechanical Engineering Department, B.P. Mandal College of Engineering, Madhepura, India, 2 Director , SLIET Longowal , Punjab 3Assistant professor in Mechanical Engineering Department, B.P. Mandal College of Engineering, Madhepura, India, Corresponding Author – Arbind Kumar Amar EMail- akamarak73@gmail.com Article History: Received: 23-09-2024 Revised: 25-11-2024 Accepted: 04-12-2024 Abstract: In this paper investigation of exergetic analysis of artificial roughness in solar thermal collector is done (STC) done. Here an investigation is done through Thermal model for artificial roughness incorporate in thermal collector is developed. Experimental trial and observations are performed in India under (25º N, 86º E) climatic nature. It is observed that on the performance account approximate 9.95 percent of deviation is seen at out let temperature of STC between theoretical and of Experimental values. Proposed STC reflects improved exergy efficiency about 2.65 %. This result predicts that improvement found in proposed STC which incorporates artificial roughness. Keywords: Solar collector; Fin efficiency; Total loss; Exergy destructions. I. INTRODUCTION The growth of any nation is equally related to use of its available energy resources or resources through their capability to do. In current scenario India’s performed well in different era such as transportation, manufacturing, agriculture & Clean energy. Fossile fuels plays very key role in India to accomplished utilization and consumption of energy. The pace & rate of use of these natural resources are very speedy and it will not be continued for coming long duration. [1, 2, and 3]. Thus, an alternative source, such as clean energy becomes etc, is equally useful. Solar energy is available for all at no cost and also release energy, at the rate of 38x1022kW, in that, just around about 18x 1013kW is falls and or intercept on earth [4]. The simple, & the upmost proficient technic to utilize this clean energy, by transforming free energy for heating application’s through STC. STC, because of their simplicity & ease, it is very cheap & most widely can be used [5]. The thermal nature or behavior of STCs’s is depends on or upon the material, its shape, Size & design of collector’s. Improvement or upgrading, in the excellence on the Performance, achieved by varying the above different parameters. Improvement on STC in order to increase the rate of heat transfer can be possible. This includes, use of absorber - (corrugated absorber or and matrix-based absorber), and with (packed bed or else baffles or & fins). Thermal investigation or analysis is given effective impact , to obtain most accurate and an important idea to predict or know energy efficiency , & different losses because of the irreversibility in and actual real state [6].First law is mostly widely , used in actual practice & also is depends on the impact , on heat balance technique etc i.e. universally used as, in the performance investigation any case. Second law involves , the reversibility and , or irreversibility of process. It is very fundamental aspects, and of exergy & energy of STC investigation’s [7]. Exergy data’s, are very practical , and are realistic , & in compare to respective energy values; Exergy Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 238 https://internationalpubls.com analysis can , provides a more realistic prediction of processes, & also sometimes different, in comparison with standard energy analysis values [8-9]. II. EXPERIMENTAL SETUP Proposed STC with finned as artificial roughness with the single pass nature is Made or fabricated. A galvanized sheet which is black coated of low or small thicknesses are used. Artificial roughness i.e. Fin’s are fixed, at back side of absorber plate, (In perpendicular position in provision that to maintained the minor linear gap from the base plate) to enhance thermal performance i.e availability in proposed STC. It works or function under forced convection, & the window fan is fitted at the place of inlet of the experimental set up. In order improve performance proposed STC is fully glass insulated with the help of this heat losses is minimized. The rate of flow of mass as air is considered 0.0361Kg/sec, 0.0392Kg/sec & 0.0421Kg/sec is throughout constant maintained through regulator over the study. Solar intensity and the wind velocity, is also noted all over study by solary meter & anemometer. K-type thermocouple, is used here in order to measure temperature at the different point of STC. 2- D Figure of artificial roughness on STC as finned absorber plate on STC shown in Fig1. Table 1. Table 1 reflects all dimension and standard parameter Total fins = 19 (a) (b) 1010 mm Figure1 Vew of Artificial roughness as finned STC. The experiments on Proposed STC is done in the Solar Energy laboratory, In Mechanical Engineering Department, B.P. Mandal College of Engineering, Madhepura, India. The experiments and readings, are recorded October, in light winter climatic & observations are noted from 8 am to 5:00 pm. III. MATHEMETICAL MODEL (a) ENERGY ANALYSIS The 2-D Presentation of STC with artificial roughness considered as finned on absorber plate, in STC under performance investigation depict in Fig.1.In the analysis for solar input energy balance empirical formulas are predicted for rate of heat and mass flow through out STC along with heat losses. Flow of heat on collector is depicted in fig 2. Energy input to system through the solar radiation impinges on 60mm Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 239 https://internationalpubls.com absorber surface. Different loss and total loss because of radiation and convection through black absorber plate is elaborated in[10, 11]. Fig. 2 Energy impact on absorber plate The energy investigation on STC is elaborated by sukhatme (1993). usable heat gain: . u pQ mC T=  (1) Hottel - Whiller empirical technique for usable heat gain obtained from STC: u c RQ A F = (2) Exit air temperature of STC: 1 o i L T T u = +  (3) Thermal Efficiency estimated in solar collector: u T p Q c I A  = (4) ARTIFICIAL ROUGHNESS AS FIN ON STC: A proposed fin on STC depicted in Fig 2. Gap in between fins W1 & the length of fin is W2. All fins as artificial roughness is fixed on back or reverse portion on plate along with minor gap to each other and with bottom plate. Efficiency factor, F’ on STC collector: [12]. ' 1 1 2 2 2 1 ' ' ' 1 o F W ho F W hP FF F oF F − +   = +    (5) ( b) EXERGY ANALYSIS: Through use of exergy equilibrium in STC shown in Fig.1, Balance of Exergy STC is elaborated by Chamoli (2013):[13] 0in out loss change des − − − − = (6) Exergy efficiency determined with use of in & outlet exergy: . 1 T p p om p o i a nI A T C T T T l T     = − −      (7) Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 240 https://internationalpubls.com DESTRUCTION ON EXERGY: Exergy destruction is happened due to irreversibility’s occurred in system. Exergy destroyed has three terms: One, Difference of temperature in between STC absorber plate surface & sun: ( )1 1 , p sdes abs o T p a T T I A T = − (8) Second, due to duct’s pressure drop: ( ) ( ) . , To p a n Ta p o in T l m des T T   −  =  (9) Third, temperature difference in between STC absorber plate surface & fluid: ( ) ( )( ) . , o ino in p T TT des conv p a n T T mC T l −  = − (10) Hence, exergy destruction: , , , , des abs des des convp in rdes  + +   = (11) As considered that drop in duct pressure is negligible, hence exergy destruction: , , , des abs des conv in rdes  +   = (12) EXERGY IN: In view of Petela’s, exact exergy on Collector surface Ap becomes: ,in r T p pI A  = (13) (c) PARAMETER RANGE: Table 1: different parameters considered for ivestigation S.No Used Parameters Ranges S.No Used Parameters Ranges 1 Glazing of glass Single glass 8 Transmttance-absoptance 0.85 2 Fluid medium Air 9 Thickness of plate δ 0.003m 3 Finn counts 18 10 Absorber plate emittance,ɛp 0.93 4 plate length L=1.25m 11 Glass cover emmitance, ɛg 0.88 5 plate width W=0.98m 12 Stefan-Boltzman constant 5.67x10-8 W/m2 K4 6 Channel Depth s=0.07m 13 Space in between fins W1 0.0659m 7 Temperature of Sun 5760K 14 Fin Length W2 .06m HEAT TRANSFER COEFFICIENTS: Heat transfer, convective or radiative can be predicted is elaborated in : [14] , radiative heat transfer: ( )( )2 2 , 1 1 1 p g p g p g T T T T r p gh    + + −      + −         = (14) Sherwin have proposed in types of laminar flow, for proposed STC modeled has suggested relations to estimate coefficient of heat transfer. Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 241 https://internationalpubls.com For ( )55 10 0.5eL rR and P   , 1 1 3 20.664u r eLN P R= Niles et al. has given following empirical relation in case of turbulent flow: For 5 85 10 10eLR   and 0.6 60rP  , 0.8 0.330.333u e rN R P= Convective heat loss: ( ) ( ) ( ) 1 1 3 20.664k c r eL h P R=    (15) LOSS COEFFICIENTS: Top loss coefficient, in single glass cover design [15, 16] : ( ) 1 1 1 cp c rp c w rc at h h h h U − − − − + + = + (16) Total loss: L t b eU U U U= + + (17) IV. RESULT AND DISCUSSION In order to obtain out let or exit temperature, different empirical relations and energy balance equations are incorporated and discussed. STC performance efficiency is made subjected to input parameters as mentioned above, the process of recording data at different points is done till sun set. At the stage of initialization plate of STC absorber is black and ambient temperature is considered as air temperature. Experimental work and readings were taken in winter season in real Indian climate & in the premises of B.P. Mandal College of Engineering, Madhepura, India. Test readings are taken throughout month and out of which moderate and good value of any particular day is considered. Fig.3 reflects, Plot of solar Intensity with time, Solar intensities are abserved here closed at different flow of mass and have the same pattern . Figure 3 Plot of solar intensity, mass flow ratee V/s span of day 0 200 400 600 800 1000 1200 1400 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 So la r In te n si ty Time It W/m2 at m=0.036 kg/sec It W/m2 at m=0.039 kg/sec It W/m2 at m=0.042 kg/sec Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 242 https://internationalpubls.com Figure 4 Plot of exit theoretical temperatures V/s different mass flow rate & Span of day Figure 5 plot of Exit practical temperature V/s different mass flow rate at span of day Fig. 4 and Fig. 5 depicts plot of out let temperatures with different mass flow rates, (0.036 kg/s, 0.039 Kg/sec & 0.042 kg/s) theoretical & practical. Out let also improves accordingly as solar Intensity in same fashion. It is found that experimental values enhanced with a limit of 10 percent then that of Theoretical values. Figure.6 Plot of Collector efficiencies V/s day time with different mass flow rate 290 300 310 320 330 340 350 360 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 T em p er a tu re Time Time Vs Out let Theoretical Temperature (Tth) m=0.036 kg/sec m=0.039 kg/sec m=0.042 kg/sec 300 305 310 315 320 325 330 335 340 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 Te m p e ra tu re Time Time Vs Out let pactical temperature ( Top) m=0.036 kg/sec m=0.039 kg/sec m=0.042 kg/sec 0 10 20 30 40 50 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 Ef fi ci e n cy Time Time Vs Collector Efficiency ɳc m= 0.036 kg/sec m=0.039 kg/sec m=0.042kg/sec Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 243 https://internationalpubls.com Figure 7 Plot of energy efficiency V/s day time with different mass flow rate Fig. 6 depicts plot of collector efficiency, with three mass flow rates verses time of day in (hr). As expected, minor variation is observed on account of overall & average collector mass flow rate. The estimated average, collector efficiency in all different three mass flow rates is obtained same as plot reflects. Fig. 7 predicts impact of thermal efficiency at the different mass flow rates, (0.036 kg/s. 0.039kg/sec and 0.042 kg/s) V/s day span. As mass flow rate, increased from (0.036 kg/s to 0.042 kg/s ) improvement in energy efficiency as 10.84%. It is found that as mass flow is higher the energy efficiency is also getting higher. In fact, due to increase in mass flow rate the impact of convective mode of heat transfer is more on-air flow at exit. Figure 8 Plot of exergy efficiency (practical) V/s time (hr) with different mass flow rate. As fig 8 depicts, practical exergy efficiency is higher at higher mass of flow rate. As mass flow rate , increases from (0.036 kg/s to 0.042 kg/s ) exergy efficiency also increases by 51%. Average practical (exergy efficiency) could be achieved by 1.724 %, 1.307 & 2.17 % at different (mass flow rate) of 0.036, 0.039 & 0.042 Kg/sec. Correspondingly. Figure 9 Plot of (exergy efficiency theoretical) V/s time Span (hr) with different mass flow rate 0 10 20 30 40 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 Ef fi ci e n cy Time Time Vs Thermal Efficiency ɳth m=0.036 kg/sec m=0.039 kg/sec m=0.042 kg/sec 0 1 2 3 4 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00 Ex e rg y Ef fi ci e n cy Time Time Vs Exergy Efficiency Practical m= 0.036 kg/sec m=0.039 kg/sec m=0.042kg/sec 0 0.5 1 1.5 10:00 10:30 11:00 11:30 12:00 12:30 01:00 01:30 02:00 02:30 03:00 03:30 04:00 04:30 05:00Ex e rg y Ef fi ci e n cy Time Time vs Exergy Efficiency Theoretical m = 0.036 kg/sec m=0.039 kg/sec m=0.042kg/sec Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 244 https://internationalpubls.com As fig 9 reflects, theoretical exergy efficiency is correspondingly higher at higher value of mass flow. At higher mass flow rate losses in exergy is reduced. As mass flow rate is enhanced from (0.036 kg/s to 0.042 kg/s ) exergy efficiency is also increases to 46%. The average practical (exergy efficiency) could find as (0.4785 %, 0.681 % & 0.7242 %) at mass flow rate (0.036 Kg/sec, 0.039 Kg/sec & 0.042 Kg/sec.) respectively. Figure 10 Plot (Exergy destruction) V/s time Fig 10 shows the trend, exergy destruction v/s time of the day. The highest average (instantaneous destruction) found be 0.86 & overall average (destruction) is found 0.88. V. CONCULSION The presented mathematical model which is used as a tool to calculate or determine different incorporated heat transfer coefficients, which impacts on the STC performance. Through mathematical tool, thermal performance on STC over unlimited range of operating range such as (solar intensity & inlet air temperature) are trialed. Middling collector efficiency of 43.32 % & maximum (instantaneous thermal efficiency) approx 36.42 % is obtained. Exergy analysis Predics maximum (exergy loss) & (exergy destruction) in the proposed STC. Average (exergy efficiency) of 0. 74% is analyzed in the present study & the (average destruction) is about 0.88. REFERENCES [1] TERI, Energy and environment data directory and year book (TEDDY) 2013/2014. 28th ed. New Delhi: The Energy and Resources Institute; 2014. [2] Grag P, Energy Scenario and vision 2020 in india. J Sustain Energy and Environment 2012;3:7-17. [3] Ghosh D, Shukla P, Garg A, Ramana P.V. Renewable energy technologies for the Indian power sectors: mitigation potential and operational strategies. Renew sustain energy Rev 2002;6(6):481-512. [4] Panwar NL, Kaushik SC, Kothari S. Role of Renewable energy sources in environmental protection: a review. Renewable And Sustainable Energy Reviews2011; 15: 1513-24. [5] Srivastava Ravish and Rai Ajeet Kumar. Studies on the thermal performance of a solar air heater. 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APPENDICES - Nomenclature: A Area (m2) Cp Specific heat capacity of the fluid ( K j /Kg k) F’ Finned collector efficiency factor FR Heat removal factor IT Incident Solar radiation (W/m2) UL Over all heat loss coefficient (W/m2-K) T Temperature (K) Q Heat transfer rate (Watt) D Hydraulic diameter (m) U Loss Coefficients(W/m2-K) T Temperature oK E,H, Value Contant (W/m2-K) h1, h2,, h3,hc ,convective Heat transfer coefficient (W/m2-K) S Absorbed solar radiation (W/m2) Re Reynolds’s No. Nu Nusselt No Pr Prandtl No L Collector length (m) W Collector width (m) s Depth of air channel (m) . m Mass flow rate (Kg/sec) hw Convective heat transfer due to wind. F Fin efficiency Greek symbols : a absorptance ɳ Efficiency τ Transmittance (τα) Transmittance-absoptance σ Stefan-Boltzman constant ɛ emmitance µ Dynamic viscosity (Kg/m-s) k Thermal conductivity ( W/m-k)  Exergy Subscripts: a ambient o outlet .optical i inlet exp exponential p plate , petla c collector u useful f fin th Thermal s Sun ,Depth of channel g Glass c Convective r Radiative t Total ,top b Back e End r Radiation abs Absorber conv Convective ( )i aT T T = − ( ) ( )2 3 ' b r t t r E o H U h h U U h h F  + + + +  = ( )2 2 tanh mW F mW F = K b l U = ( )L i aS u T T  = − −  2 bE H h U= + 2h k m  = ( ) edge c UA e A U = . ' 1 exp c L p A u F mC     = − −     ( )2 3 2 3r rH h h h h h h= + + ( ) 4 4 1 3 3 a a s s T T p T T  = + cA s W=  . p c L mC R A u F =  1 1 t h p h U F + = 5.7 3.8wh V= +  2 4 2W s W D s= =   Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 4s (2025) 246 https://internationalpubls.com FLOW CHART: Start Input parameters It, ,Ti , Ta ,To ,Tg,Ts, Tp,Tb, TPCM, Tpcm 1,Tpcm2, Dh,Ah, k, L, Pr, µ ,Cp, ξabs, ξg, σ, Va, δe, λi , L1 L2,L3,Aabs.,ηo, α,τ, F, Tin_chPCM, Tfin_chPCM, Cps,Cpl. Set , initial value of different parameters Tg=Tp-2 , TPCM = 0.5x( Tpcm 1 + Tpcm 2 ) Calculate the values of, Renold’sNo ,,Heat transfer coefficients, Other &Total loss, constants ,HR factor Re, hc_abs, hr_abs ,hr_ga ,Ub, Ue, Ut ,Uloss, E, H, F FR , S, Qu , Top hw= (5.67+3.86Va) ≤ 10 Set hw Calculate the following parameters MPCM, ηc , ηth , ηp ,Ψp ,Ψth ,Edes Stop