Experimental Heat Transfer Research Articles

Experimental Study on Combustion and Heat Transfer Characteristics of Li/SF6 based on Unmanned Underwater Vehicle Combustor

Abstract The Li/SF6 combustion reaction can provide power for unmanned underwater vehicle (UUV) due to the advantages of high heat release and no gaseous combustion products. Exploring the combustion and heat transfer characteristics of Li/SF6 can greatly improve the performance of the UUV combustor. In this paper, based on the operation requirements of UUV combustor, the C300 combustion reactor is designed, the Li/SF6 combustion experimental system is established, and the Li/SF6 combustion and heat transfer experiments are performed. The experimental results show that the overall combustion process lasts about 1.55 h, and the flame temperature is higher than 1768 °C. The temperature in the gas phase decreased gradually along the radial direction and increased along the axis. Eight quasi-equilibrium states are detected, and the maximum combustion power is 12.73 kW. As the pressure increases, the combustion power will increase accordingly. Under the maximum power, the heat transfer efficiency of the C300 combustion reactor can be calculated to be η=85.93% by using water as the heat transfer medium. The heat transfer quantity of the combustion furnace Qf is 2.07 times that of the combustion chamber Qc, and the heat generated by combustion is concentrated in the lower part of the combustion reactor. In addition, a thermal resistance model is proposed to optimize the heat transfer process. Finally, the upper fuel is fully combusted, while the bottom fuel is poorly combusted due to the phenomenon of insufficient melting and combustion product covering.

Heat transfer performance of a novel PCM based heat sink coupled with heat pipe: An experimental study

Thermal management is vital for all electronic applications due to the system’s considerable heat output. The improvement of the charging time for a continuous operation has been the subject of much research to date. However, for intermittent operations, which are most likely to be experienced in practical applications are considered, a reduction in the heat discharge time from the heat sink is equally as essential as an improvement in the charging time. The main aim of this study is to develop a strategy that enhances the charging cycle performance and performs well during the discharging cycle as well.This paper reports the experimental heat transfer results of a novel n-Eicosane phase change material (PCM) based finned heat sink coupled with a heat pipe for electronic thermal management. Heat transfer experiments are performed on four heat sink (HS) configurations: heat sink (i) without a fin, (ii) with a circular stem at the center, (iii) with three longitudinal plate fins having a central gap for heat pipe provision, and (iv) with four longitudinal plate fins. A circular heat sink having an outer diameter of 58 mm and 55 mm in height with a wall thickness of 4 mm is considered for all the heat sink configurations. The fill ratios considered are 33, 66, and 99%. The heat input given to the plate heater is varied between 8 and 12 W. Results show that the HS performs best at a PCM fill ratio of 99%. A sintered heat pipe is coupled with a three fin heat sink. Finned heat sink with heat pipe (FHSHP) enhances the (i) charging time by 21.1%, 15.41%, and 21.65%, (ii) discharging time by 22.5%, 23.25%, and 21.25% compared to a heat sink with three fins for the power level of 8, 10, and 12 W, respectively. Further, the overall effectiveness is high for the FHSHP compared to all the geometries considered in the present study. The novel design (FHSHP) is advantageous from an engineering standpoint for efficient thermal management of electronic components.

Porosity Effect of Polystyrene Membranes on Desalination Performance: A Combined Experimental and Numerical Heat and Mass Transfer Study in Direct Contact Membrane Distillation.

Membrane distillation (MD) is a thermal-based membrane operation with high potential for use in the treatment of aqueous streams. In this study, the linear relationship between the permeate flux and the bulk feed temperature for different electrospun polystyrene membranes is discussed. The dynamics of combined heat and mass transfer mechanisms across different membrane porosities of 77%, 89%, and 94%, each with different thicknesses, are examined. The main results for the effect of porosity with respect to the thermal efficiency and evaporation efficiency of the DCMD system are reported for electrospun polystyrene membranes. A 14.6% increase in thermal efficiency was noted for a 15% increase in membrane porosity. Meanwhile, a 15.6% rise in porosity resulted in a 5% increase in evaporation efficiency. A mathematical validation along with computational predictions is presented and interlinked with the maximum thermal and evaporation efficiencies for the surface membrane temperatures at the feed and temperature boundary regions. This work helps to further understand the interlinked correlations of the surface membrane temperatures at the feed and temperature boundary regions with respect to the change in membrane porosity.

Experimental assessment of the similarity law for a one-dimensional coupled heat and water vapor diffusion in hemp concrete

Similarity law is a mathematical mapping that aims to set up equivalences between different configurations regarding the involved physical parameters, space dimensions and the duration of the configuration. These equivalences are defined by means of the dimensionless formulation of the physical model that describes a phenomenon. This concept is widely adopted in some scientific fields, notably in computational fluid dynamics. In heat and water vapor diffusion, similarities are applicable theoretically on configurations distinct in terms of material, space dimensions, duration or even imposed stress magnitude. It is worth noting that these are slow kinetic phenomena. In this regard, this study aims to verify similarities experimentally while using hemp concrete and reducing the duration of a reference experiment. Before performing measurements, two main limitations are fixed. First, by means of an experimental design, heat and moisture transfer are assumed one-dimensional. In addition, Dirichlet boundary conditions are considered at the surface that is exposed to ambient air. Mainly, temperature and relative humidity are measured at the quarter and middle of the material in order to compare the two similar configurations. Afterwards, an uncertainty study is carried out in order to discuss and justify the observed discrepancies. Following a deterministic approach, this investigation considers five sub-uncertainties which are related to : the calibration of used sensors, their positions, time of response, randomness of an experiment and the boundary condition modeling. Results show a good agreement between the reference and reduced configurations. Indeed, the discrepancies between both are entirely within the calculated confidence intervals.

Two mathematical models of flow boiling and flow instability in rectangular expanding microchannel heat exchangers and structure optimization

Flow boiling instability in microchannels was widely studied to improve the reliability of microchannel heat exchangers. Two rectangular expanding microchannel heat exchangers have been experimentally investigated, one channel with cross-cutting and the other without cross-cutting. This study aims to optimize the heat transfer capabilities of heat exchangers. Two mathematical models containing heat transfer correlation and instability parameters have been developed. The experimental heat transfer coefficient (HTC) was used to validate them. Based on the models, the structure of the expanding microchannel was optimized, and the effect of expanding microchannel on flow instability was analyzed. As analyzed, in the models for two heat exchangers with and without cross-cutting, the mean deviations are 10.03% and 5.95%, respectively. The effect of flow instability suppression increases with the increase of the radiation angle. Moreover, the cross-cutting in expanding microchannels could further steady flow when adding fins in downstream channels. When adjusting the number of cross-cutting in cold plates from 1 to 4, the maximum increment of HTC is 58.17 kW/(m2·K). The influences of adjusting the number of fins in microchannels on the HTC are obvious for cold plates without cross-cutting. When the position of added fins is moved downstream in channels, the HTC of the heat exchanger could be increased by 26.58%. The results of this study provide some insights for inhibiting flow boiling instability and further optimizing the expanding microchannel structure to enhance heat transfer capability.

Enhanced thermal properties of epoxy composites by constructing thermal conduction networks with low content of three-dimensional graphene

Micro/nano electronic devices heat dissipation depends heavily on the thermal interface materials (TIMs). Despite notable progress, it is hard to efficaciously enhance the thermal properties of the hybrid TIMs with high-load additives due to an absence of effective heat transfer routes. Herein, the low content of three-dimensional (3D) graphene with interconnected networks is adopted as the additive to improve the thermal properties of epoxy composite TIMs. The thermal diffusivity and thermal conductivity of the as-prepared hybrids were dramatically improved by constructing thermal conduction networks after adding 3D graphene as fillers. The 3D graphene/epoxy hybrid’s optimal thermal characteristics were observed at 1.5 wt% of 3D graphene content, corresponding to a maximum enhancement of 683%. Besides, heat transfer experiments were further performed to determine the superb heat dissipation potential of the 3D graphene/epoxy hybrids. Moreover, the 3D graphene/epoxy composite TIM was also applied to high-power LED to improve heat dissipation. It effectively reduced the maximum temperature from 79.8 °C to 74.3 °C. These results are beneficial for the better cooling performance of electronic devices and provide useful guidelines for advancing the next-generation TIMs.

Experimental study on spray cooling heat transfer performance of R245fa/R142b mixture in boiling regime

In this paper, the combination of spray cooling technology and non-azeotropic mixture was proposed to achieve the precise temperature control of heated surface. Experiments were performed with R245fa/R142b as the working fluid to study the spray cooling heat transfer of non-azeotropic mixture in boiling region. With the phase Doppler anemometer (PDA), the spray characteristics of working fluid at different height and mixing ratio were studied. The results showed that the non-azeotropic mixture existed a mixing ratio, at which the smallest droplet Sauter mean diameter (SMD) and the largest droplet density were obtained. This is beneficial to spray cooling heat transfer, and the mixing ratio is defined as the optimal mixing ratio. Heat transfer experiments proved that the surface uniformity of spray cooling is the best under the mixing ratio corresponding to the optimal spray characteristics. Further studies found that, at low heat flow in the two-phase region, the spray heat transfer performance of the non-azeotropic mixture was significantly weakened compared with that of any single component. With the increase of heat flux, the heat transfer performance of the non-azeotropic mixture gradually exceeds that of the single component R142b, which is related to the effect of additional mass transfer resistance in different stages.

Optimization of metal foam pellet shape in packed beds for improved radial heat transfer using particle-resolved computational fluid dynamics

Process intensification in tubular reforming reactors has always been a topic of interest, particularly for improving the radial heat transfer. The innovation of open-cell metallic foam pellets is the latest in this category, as they bear unique transport properties. This work presents the optimization of metal foam pellet shapes for improved radial heat transport, using a virtual design platform based on a modified version of particle-resolved computational fluid dynamics. To optimize the pellet geometry, different configurations such as pellet with inner holes, external grooves, and varied aspect ratios, as well as different foam morphologies (cell size ϕ and porosity ε) are considered, and the influence of each pellet configuration on flow and energy transport in a randomly packed bed setup has been investigated. Based on the desirable properties of the packed bed, such as low pressure drop, high heat transfer coefficient, increased surface area, and high catalyst inventory, the overall performance of the investigated pellet shapes is analyzed. The foam ring with the aspect ratio of 2.5 and ϕ = 0.45 mm, ε = 0.82 has been identified as optimal under the investigated operating conditions 250 < ReP < 2250, which is confirmed by pressure drop and heat transfer experiments.

Effect of mass flow ratios on the conjugate heat transfer of a metal turbine vane at medium temperature

To investigate the effect of mass flow ratios on the conjugate heat transfer of an air-cooled turbine vane, the surface static pressure test experiments and heat transfer experiments at medium-temperature (407.3 K) and medium-pressure (98.49 kPa) were conducted. An infrared thermal imager was used in the experiments to measure the temperature distribution of the test vane's outside surface. The effects of MFR (mass flow ratio), and mainstream Reynolds number were investigated. The experimental results show that the vane surface temperature is affected by both internal and external cooling. When the MFR was relatively small (MFR=1.0%, 2.0%, 3.0%), the integrated cooling effectiveness on the pressure surface gradually decreased along the coolant passage. At the same MFR, due to the different flow states on the vane surface, the integrated cooling effectiveness corresponding to the maximum mainstream inlet Reynolds number (2.64 × 105) was the smallest, and the cooling effect deteriorated most noticeably at the leading edge. The cooling effect deterioration at the leading edge occurred when the MFR was lower than 4.0%. In addition, the growth rate of integrated cooling effectiveness prior to MFR=4% was significantly higher than that after 4.0%. When the MFR increased from 1.0% to 4.0%, the integrated cooling effectiveness increased by 89.8% with a faster growth rate, whereas it only increased by 14.9% when the MFR increased from 4.0% to 7.0%. An empirical correlation of the spanwise-averaged cooling effectiveness was also obtained. The mean relative error of the pressure surface was 7.64%, and that for suction surface was 3.27%.

Experimental and numerical investigation of the use of new generating refrigerant R513A in the gravity-assisted heat pipe

In this study, theoretical–experimental and life cycle climate performance analyses of the gravity-assisted heat pipe filled with R513A were carried out. The heat carried by the heat pipe and the internal heat transfer coefficients of the evaporator and condenser were investigated. As the temperature set value (30, 35, 40, 45, 50 °C) increased, the heat transferred by the heat pipe increased and the averaged experimental data were obtained as 27.65, 49.30, 74.95, 99.40, 114.90 W, respectively. For the given temperature set values, the experimental internal heat transfer coefficient of the evaporator was obtained as 946, 1125, 1360, 1652, and 1215 Wm−2 °C−1. Experimental condenser internal heat transfer coefficients were obtained as 1385, 1460, 1527, 1563, and 1417 Wm−2 °C−1. According to the life cycle climate performance analysis of the given system, it has been determined that 82.22 % of the total emissions are caused by direct emissions and 17.78 % by indirect emissions. Direct emissions are related to leaks of the working fluid. Choosing a low global warming potential working fluid will significantly reduce emission and thus reduce the overall emission of the gravity-assisted heat pipe.

Experimental Investigation of InTube Condensation of HFO-1234yf

An increase in global warming potential and other environmental concerns are demanding new environmentally friendly refrigerants. For effective performance of refrigeration and air conditioning system condenser design play a vital role. Experiments were conducted to study the condensation of R1234yf refrigerant inside a copper tube of 8.4 mm in diameter and 750 mm in length. The heat transfer coefficients of refrigerant were calculated against mass flux varying from 150–300 kg/m2 s, quality of refrigerant 0.3 to 0.8, and saturated temperature 30 and 500 C. The experimental heat transfer coefficients were compared to the heat transfer coefficients by the recent MM Sha correlation. The experimental results are in good agreement with an absolute mean deviation of nearly 20% with the MM Sha heat transfer coefficient.

Experimental Heat Transfer Performance of Plate Fin Heat Exchanger Based on Fuzzy Algorithm

Experimental Heat Transfer Performance of Plate Fin Heat Exchanger Based on Fuzzy Algorithm

Edney III type shock-shock interaction over a hemisphere cylinder

The interaction of an oblique shock wave with a bow shock in front of a hemisphere at Mach 14.6 is simulated. The configuration corresponds to an experiment performed at the Calspan University of Buffalo Research Center (CUBRC). Several simulations were performed to assess numerical uncertainty and to achieve agreement with the location of the computed and experimental peak surface pressure and heat transfer. Three simulations are presented for the former and two simulations are presented for the latter. Of the latter two simulations, the first simulation showed statistically stationary behavior in the surface pressure and heat transfer with unsteady periodic laminar behavior in the surface pressure and heat transfer, but the location of the computed peak surface pressure and heat transfer differed from the experiment by three degrees on the surface of the hemisphere. The second simulation with a different incident shock location showed close agreement between the locations of the computed and experiment peak surface heat transfer; however, the results in this case indicate unsteady non-periodic behavior.

Experimental investigation of the effects of metal oxides and nucleating agents on nano-emulsions heat transfer performance in mini-channels

Recently, thermal conductivity, even and stable suspension of particles, and agglomeration of particles have been studied comprehensively. These properties are especially important parameters for nanofluids in small-size heat transfer devices like mini-channels, which are prone to block due to the small size of the channels. In the present study, a method was proposed to increase heat transfer using composite nano-phase change emulsions (NPCEs) slurries, utilizing the latent heat of PCM during melting. In this experimental study, a series of composite nano-phase change emulsions (NPCEs) with high thermal conductivity, high thermal storage, and low supercooling were developed and prepared from hexadecane, octadecane, hexadecanol, octadecanol, and nano-Al2O3. Heat transfer experiments were conducted in a mini-channels using the prepared NPCEs as working fluids. The effects of the nanoparticle concentration, NPCE type, and flow rate on multiple parameters, including the heat transfer coefficient, flow resistance, and heat transfer performance of composite NPCEs were investigated. As a result, the heat transfer experiments demonstrated that the proposed NPCEs as heat transfer fluids could enhance the heat transfer performance in mini-channels in comparison with deionized water. Compared with deionized water, the convective heat transfer coefficient was increased by a maximum of 1.28 %, 4.07 %, and 4.19 % with an octadecane concentration of 5 wt%, 10 wt%, and 20 wt%, respectively. The nano-emulsion with a combination of 5 wt% hexadecane, 5 wt% octadecane, and 1 wt% nano-Al2O3 achieved a maximum increase of 7.01 % in the heat transfer enhancement factor. In addition, the nano-emulsion with a combination of 5 wt% hexadecane, 5 wt% octadecane, and 1 wt% nano-Al2O3, in addition to 1.25 wt% hybrid nucleating agents allowed a maximum increase of 26.49 % in the heat transfer enhancement factor. The obtained results and performed analyses demonstrate that metal particle-composite alcohol hybrid nanofluid has high stability, high thermal conductivity, low subcooling, high durability, and a convenient preparation method, and is an appropriate choice as a working fluid, especially in small-scale heat transfer devices.

Modelling and experimental validation of heat transfer behavior during trans-critical transients

Though designed to be operated in supercritical conditions, supercritical power systems could experience trans-critical transients in which the pressure transfers between supercritical and subcritical condition during startup, shutdown, or accident condition. In the present work the thermal–hydraulic code ATHLET-SC was upgraded to predict the heat transfer behavior during trans-critical procedures. Prediction model of dispersed droplet flow film boiling (DFFB) heat transfer correlation, critical heat flux (CHF) correlation, and the correlation of minimum film boiling temperature TMFB has been upgraded. It is demonstrated by the validation work that the prediction error is large in the inverted annular film boiling (IAFB) regime. However, steady-state IAFB heat transfer experiment at high-pressure condition is unavailable. Hence, a calibration approach to IAFB heat transfer correlation is developed based on trans-critical transient experiment. As validated, the change of the wall temperature during the trans-critical transient gets well predicted by the corrected Bromley correlation.

Thermal performance analysis of a new type of branch-fin enhanced battery thermal management PCM module

To solve the problem of the lightweight design of metal fins and strengthen the heat transfer between phase change material (PCM) and lithium batteries, the synergistic design of fins and phase change material-battery thermal management system (PCM-BTMS) is particularly important. In this paper, 9 new branch fin design schemes were proposed based on the conventional straight fin. The reliability of the computational fluid dynamics model was verified through the heat transfer experiments at different discharge rates. Firstly, the thermal performances of 9 new fins and the conventional straight fin under 5C discharge rate were compared and analyzed, and the optimal model was selected. Secondly, the effects of transverse fin coverage area, number, arc length, thickness, and arc length of inner and outer arc fins on the thermal performance were analyzed considering the effects of different heat transfer coefficients. The results show that the preferred fins have less effect on the heat transfer coefficient enhanced thermal performance compared with the conventional fins; the average cell temperature is reduced by 3.14 K and 3.92 K respectively by increasing the fin coverage area and the number of transverse fins to increase the contact area with PCM to enhance heat dissipation; the average cell temperature changes more significantly with the inner arc fins, and the cell temperature of Case H6 was reduced by 7.2 K; while the transverse fin arc length extension reduced the thermal performance of the system in high temperature cases. The volume of system remained the same, and the thickness of the transverse fins decreased the heat storage capacity of the system when the thickness of the transverse fins was larger. The optimal fins could keep the average cell temperature within 318.15 K. The heat transfer capability was improved by 14.98%, the operating time was extended by 131.5%, and the system weight was reduced by 10.28%.

Experimental investigation on high-temperature flow boiling heat transfer characteristics of R245fa in a horizontal circular tube

Working fluid is the lifeblood of thermodynamic cycle for its heat transfer behaviour is critical to the design of heat exchangers in a thermodynamic cycle. Though being widely applied in organic Rankine cycles and high-temperature heat pump cycles, R245fa has witnessed little research on its high-temperature flow boiling heat transfer characteristics by far. In the present study, an experimental investigation on the flow boiling heat transfer characteristics of R245fa with a mass flux of 248–460 kg·m−2∙s−1, a heat flux of 5.5–17.3 kW·m−2 and an evaporating temperature of 80–115 °C in an inner diameter of 10 mm horizontal smooth circular tube is conducted. The influences of vapor quality, mass flux and evaporating temperature on the flow boiling heat transfer coefficient are also analyzed. The comparison of experimental heat transfer coefficients and the predicted heat transfer coefficients based on five heat transfer coefficient correlations is conducted and it is discovered that Gungor and Winterton's correlation with a mean deviation of 20.4% gives the best fit to the experimental data. Thus, based on Gungor and Winterton's work, an improved heat transfer coefficient correlation with a mean deviation of 12.8% is developed, in which 95% of the data points fall within the range of ±30%.

CorTAF: A nuclear reactor core three-dimensional thermal-hydraulic characteristics analysis code based on OpenFOAM

In this paper, a thermal hydraulic analysis method based on open source CFD platform OpenFOAM was proposed. The models of coolant flow and heat transfer, fuel rod heat conduction and coupled heat transfer were established according to the bundle structure characteristics of PWR core, and then a nuclear reactor three-dimensional thermal–hydraulic characteristics analysis code CorTAF was developed based on finite volume method with the spatialresolution of subchannel level. The international benchmarks, including GE3 × 3, Weiss and PNL2 × 6 fuel assembly flow and heat transfer experiments, were selected to carry out the validation. The calculation results were basically consistent with the experimental data, illustrating that CorTAF is suitable for predicting the flow and heat transfer characteristics of coolant in the rod bundle fuel assembly. The thermal–hydraulic characteristics of fuel assembly and PWR core under full power operation and blockage accident conditions were simulated using CorTAF. The steady-state and transient spatial distribution of physical quantities in subchannel-scale including coolant and fuel rod temperature were obtained, and the influence of blockage condition on flow and heat transfer characteristics was analyzed. This work has reference significance for the development of core thermal hydraulic analysis tools for PWR.

Effect of shape-stable phase change materials on heat transfer characteristics of ground source heat pump backfill materials

Ground source heat pump (GSHP) systems can utilize shallow geothermal energy to realize low-carbon buildings. The backfill material used in GSHPs directly affects the heat exchange between the ground heat exchanger and soil. Phase change materials (PCMs) can utilize the phase change process to realize both the storage and release of energy. Applying PCMs to GSHP backfill materials may be beneficial towards improving efficiency and saving energy. In this study, decanoic acid and lauric acid were used as composite PCM and graphite powder was added to enhance thermal conductivity. Expanded perlite was used as absorbent and silica sol was used to shape and encapsulate PCM. A shape-stable phase change material (SSPCM) was prepared for GSHP backfilling. Basic characteristics including thermal conductivity of SSPCMs were assessed and analyzed, and one-dimensional heat transfer experiments were carried out. The results showed that at a decanoic acid to lauric acid mass ratio of 7:3, the phase change temperature of binary organic acids is 19.9 °C, and the latent heat of phase change is 124.03 kJ/kg. At a 60% mass content percentage of PCMs, the amount of added graphite powder was 4%, the thermal conductivity of the SSPCM encapsulated by silica sol was 0.1431 W/(m·K), and the mass loss rate of SSPCM was less than 5% after 25 high and low temperature cycles. Materials with the above parameters have suitable comprehensive properties and can be used as preferred phase change backfill material for GSHP. The thermal conductivity of the backfill material is negatively correlated with the mixing ratio of SSPCM, and positively correlated with water content. At an intermittent ratio of 10:14, after 10 h of heating, the temperature range of the phase change backfill sample was 0.38–7.45 °C lower than that of the original soil backfill sample; after 14 h of cooling, the temperature of the phase change backfill sample was closer to the initial temperature. Therefore, adding SSPCM to the backfill material is beneficial to the long-term intermittent operation of GSHPs.

Estimation of thermal contact conductance of spacecraft heat sink bolted joints

Efficient thermal management is one of the key steps required to minimize failure and enhance the lifespan of electronic packages deployed in space applications. Precise and accurate knowledge of thermal contact conductance at the electronics package — heat sink interface is a key input required to achieve the efficient design of heat sinks for the mentioned application. In this study, a novel non-intrusive method for estimating the spatially varying thermal contact conductance for thin-plate bolted joints used in spacecraft thermal control systems is presented. A five bolt configuration joining the electronics package base plate to the heat sink plate is considered. Different bolt torques and their effect on the interface thermal contact conductance between the plates are investigated. Using pressure-sensitive films, the actual contact area and its spatial variation is determined for each torque level in the range of 1.5 N m to 9.0 N m and the contact interface is divided into three regions. Heat transfer experiments are carried out in vacuum at a pressure of 1×10−6 mbar for different combinations of bolt torques, heat load and heat sink temperatures. The thermal contact conductance values over the three regions are simultaneously estimated using an inverse parameter estimation technique. To improve the computational accuracy of the estimation process, a two stage stochastic optimization technique using the Monte-Carlo random sampling algorithm is used and the obtained estimates are compared. With an increase in applied bolt torque from 1.5 N m to 6.0 N m, the actual contact area and the area weighted interface thermal contact conductance are found to increase by 72.26% and 138.82%, respectively. Furthermore, the stochastic estimates of the spatially varying thermal contact conductance obtained using the developed methodology are found to follow a normal distribution with the average limit of standard deviation being ±7.34%, ±6.26% and ±13.22% of the mean values for the considered three regions respectively.