Heat Flux Intensity Research Articles

Thermal Exploration of Combined Rectangular and Semi-Circular Artificial Ribs in the Flow Regime of Solar Air Heater: A Computational and Experimental Approach

Abstract A roughened solar air heater is developed numerically and experimentally with a novel roughness in the absorber. The roughness incorporated is a combination of rectangular and semi-circular ribs. The analysis is done to improve the thermal characteristics considering two cases. Type A with ribs placed above the absorber and Type B with ribs placed below it. Several operating parameters are investigated including heat flux, Reynolds number (Re), relative obstacle relative height (h/H) ranging from 400 W/m2 to 1000 W/m2, 4000 to 10,000, and 0.4 to 1.0, respectively. The relative pitch is kept constant at 15 mm. The governing equations are simulated employing the renormalization group k–ε turbulence flow model. The results indicated that both Type A and Type B achieved significant improvements over the smooth duct. Type A exhibited a maximum Nusselt number of 4.24, while Type B achieved 3.93 in comparison with smooth duct at Re of 10,000, respectively. The thermal enhancement factor (TEF) ranges from 1.32 to 1.79 for Type A and 1.26 to 1.69 for Type B at a heat flux intensity of 1000 W/m2. Also at a relative height of 1.0, Type A demonstrated the highest TEF of 1.79 at Re = 10,000 and provided a maximum exergy efficiency of 11.2%.

Combinatorial approach to predict synergistic ablation behavior of carbon fiber phenolic composites under aerodynamic loading

The study conducts a comprehensive analysis across 1-D, 2-D, and 2-D axisymmetric geometries, investigating temperature profiles, surface recession patterns, pyrolysis gas flow dynamics, and density fluctuations within the composite material. The findings highlight the effectiveness of the FEA technique in modeling complex multi-physical interactions associated with ablation phenomena. The carbon-phenolic composites, characterized by low thermal conductivity, high specific heat capacity, and substantial char yield, are shown to be particularly well-suited as ablative materials. The char layer formed during ablation acts as an additional insulating barrier, enhancing thermal protection. In a specific case study, a 2 cm thick composite laminate was subjected to an intense heat flux of 200 W/cm2 for 180 s. The results demonstrate that the Thermal Protection System (TPS) effectively maintains the back face temperature below 350 K for the initial 60 s under uniform heat flux conditions. However, beyond this period, the back face temperature gradually increases, reaching 1698 K at the end of the 180-s simulation. These insights into the material’s thermal performance under severe heat exposure conditions provide valuable guidance for applications requiring effective heat management and thermal protection.

Study on the effect of structural parameters of a thermal liner on its thermal protective performance under radiant heat exposure

To comprehend the impact of elementary construction parameters of nonwoven thermal liners on their thermal protective performance, the current research primarily emphasizes on studying the effect of needle penetration depth and needle punch density of the thermal liner. Nonwoven fabrics with three different punch densities and three needling depths were prepared. The air permeability and thermal resistance of the thermal liner were investigated through regression analysis to determine the influence of needle penetration depth and needle punch density. It was observed that both factors had a notable impact on the air permeability and thermal resistance of the thermal liner. An increase in needle penetration depth and needle punch density resulted in a decrease in the air permeability and thermal resistance of the thermal liner. An experiment was carried out utilizing the 33 Box-Behnken designing approach; the factors employed were the radiant heat flux intensity, needle punch density, and needle penetration depth of the thermal liner. The thermal protective performance of thermal liners was measured at three discrete intensities of radiant heat exposures. To investigate the effect of the test and construction parameters and their interaction, an analysis of variance study was carried out. It was observed that protection time rises with the decrease in needling depth and needle punch density at every level of heat flux. With the rise in incident radiant heat flux, protection time declines, irrespective of needle penetration depth and punch density levels.

Horizontal Heat Flux Spread in an Inner Corner of Buildings

This study investigates fire separation distances as essential means of passive fire protection in building design. The focus is on the inner corner configuration of building exterior walls, which represents the worst-case scenario for façade fire spread outside of a building. The inner-corner configuration appears to increase the intensity of the radiative heat flux due to reflection and reradiation of heat. Comprehensive approaches for determining fire separation distances around the various façade geometries can be found, but none of them is focused on detailed descriptions of the unprotected area in an inner corner. A medium-scale scenario was chosen and was experimentally validated with a radiant panel for a better understanding of heat flux spread. This paper compares the experiment with analytical and numerical models. The analytical model is based on the Stefan–Boltzmann law and the calculated configuration factor as per Eurocode 1. The numerical model combines radiative and convective components of the heat flux because convection is non-negligible near the heat source. Experimental data confirm the prediction based on the numerical and analytical model and show agreement. The final increase in heat flux due to the corner configuration investigated at the medium scale reaches up to 29%.

Numerical Study of Heat Transfer Enhancement Using Nano-Encapsulated Phase Change (NPC) Slurries in Wavy Microchannels

Researchers have attempted to improve heat transfer in mini/microchannel heat sinks by dispersing nano-encapsulated phase change (NPC) materials in base coolants. While NPC slurries have demonstrated improved heat transfer performance, their applications are limited by decreasing enhancement at increased flow rates. To address this challenge, the present study numerically investigates the effects of wavy channels on the performance of NPC slurries. Simulation results reveal that a wavy channel induces Dean vortices that intensify the mixing of the working fluid and enlarge the melting fractions of the NPC material, thus offering a significantly higher heat transfer efficiency than a straight channel. Moreover, heat transfer enhancement by NPC slurries varies with the imposed heat flux and flow rate. Interestingly, the maximum heat transfer enhancement obtained with the wavy channel not only exceeds the straight one, but also occurs at a higher heat flux and faster flow rate. This finding demonstrates the advantage of wavy channels in management of intensive heat fluxes with NPC slurries. The study also investigates wavy channels with varying amplitude and wavelength. Increasing the wave aspect ratio from 0.2 to 0.588 strengthens Dean vortices and consequently increases the Nusselt number, optimal heat flux, and overall thermal performance factor.

Simulated temperature of a tungsten spot facing large plasma heat loads

In fusion devices like ITER, plasma-wall interactions are a significant concern due to the high heat fluxes, often tens of MW/m2, impacting the first wall. These intense heat fluxes can lead to the formation of hot spots on components facing the plasma, such as tungsten, used in divertor plates and antennas. This results in material erosion and plasma core contamination. Our study investigates the thermal behavior of tungsten surfaces under these conditions using fluid modeling and Particle-In-Cell (PIC) simulations. We examine the effects of thermionic electron emission on the sheath potential and heat transmission. The simulations reveal that thermionic emission can decrease the sheath voltage, increasing the surface temperature due to enhanced heat flux due to electrons. Additionally, we explore how the ratio between the spot size (S) and the surrounding surface length (Ly) influences the surface temperature. We find that a higher Ly/S ratio allows the surface to reach higher temperatures before the system enters the space-charge-limited regime, where thermionic current is maximized and considerably larger than the case where the entire surface is emissive (Ly=S).

Investigation on the restrain effect of air curtain to the spilled flame and its heat flux of a compartment-facade fire

This paper investigates the restrain effect of air curtain to the spilled flame and its heat flux of a compartment-facade fire. A compartment model of 1.2 m × 0.9 m × 0.9 m is established in this study, and an air curtain is facilized at the compartment opening for fire protection. The air curtain jet velocity, the heat release rate as well as the opening dimension are changed as representative to typical fire scenarios. Flame behavior and heat flux profile of spill plume are captured by CCD cameras and water-cooled heat flux gauge for discussion. Results show that the air curtain jet could have a substantial impact on the flame behavior of spilled plumes from a compartment-facade fire. Compared to that of free condition without air curtain, the flame height becomes 20 % lower as the jet velocity to be 2 m/s, while it becomes 60 % lower as the jet velocity to be 5 m/s. At the meantime, the spilled plume is noticeably influenced by the “restricting effect” of the air curtain and thus flame trajectory is significantly flattened by the inertia force of the air curtain but also pushed farther from the facade wall, resulting in an increasing of flame depth. The decreasing in flame height plus the increasing flame depth would result in the reduction of heat flux intensity upon the facade wall, which is helpful for the fire protection of the facade wall. Then, a normalized factor of Υ is further proposed to the new correlation of flame height under various air curtain jet conditions at the opening. Regarding to different ejected flame behavior at the presence of air curtain jet, the heat flux upon the facade wall is quantitative analyzed to evaluate the thermal impact of spilled plume from the compartment fire. Finally, new correlations of the vertical heat flux upon the facade wall could be well achieved by a function of normalized height factor Z/Zf, v.

Performance assessment of firefighter protective clothing under different thermal environments: Impact of the variation of thickness in inter-layer airgap and microclimate

Personal protective equipment for firefighters can effectively prevent skin burns and ensure firefighters' safety. Considering a variety of fire environments faced by a firefighter, the present study is devoted to showing the role of the inter-layer fabric airgap and its variation in thickness on skin burns under high intensity heat flux. The present numerical model is formulated by considering a coupled conduction and radiation heat interaction in the porous fabric medium and the Pennes bioheat transfer model for the multi-layered skin. The study considers the effect of variation in airgap thickness, variation in heat transfer coefficient, and duration of exposure on the thermal damage of the firefighter's skin subjected to different harsh thermal environments. The results found that increasing the thickness of AG1 and AG2 does not yield a significant impact during the exposure time. Conversely, AG3 and AG4 lead to considerable temperature reductions at the basal layer, with AG3 causing a decrease of 2.6 °C to 2.9 °C and AG4 causing a decrease of 11.9 °C to 17.0 °C under all exposure conditions. Additionally, when the heat transfer coefficient increases during post-exposure, temperature drops of 9.17 °C to 10.72 °C, 9.81 °C to 11.46 °C, 10.0 °C to 11.64 °C, and 8.68 °C to 10.07 °C are observed for AG1, AG2, AG3, and AG4, respectively, across all exposure conditions. However, both the airgaps have a substantial effect on thermal protection during the post exposure period. In addition, the nature of the variation of stored and transmitted energy in fabric assembly shows an opposite trend during both the exposure and post exposure period in contrast to the third and fourth airgaps for all the considered thermal environments.

Sustained North Atlantic warming drove anomalously intense MIS 11c interglacial

The Marine Isotope Stage (MIS) 11c interglacial and its preceding glacial termination represent an enigmatically intense climate response to relatively weak insolation forcing. So far, a lack of radiometric age control has confounded a detailed assessment of the insolation-climate relationship during this period. Here, we present 230Th-dated speleothem proxy data from northern Italy and compare them with palaeoclimate records from the North Atlantic region. We find that interglacial conditions started in subtropical to middle latitudes at 423.1 ± 1.3 thousand years (kyr) before present, during a first weak insolation maximum, whereas northern high latitudes remained glaciated (sea level ~ 40 m below present). Some 14.5 ± 2.8 kyr after this early subtropical onset, peak interglacial conditions were reached globally, with sea level 6–13 m above present, despite weak insolation forcing. We attribute this remarkably intense climate response to an exceptionally long (~15 kyr) episode of intense poleward heat flux transport prior to the MIS 11c optimum.

Performance analysis of a refrigeration system integrated with a thermoelectric cooler and microchannels in terms of heat transfer using a hybrid nanofluid

Advancements in chip technology increase energy consumption due to larger chip capacity, leading to intensive heat flux generation. Cooling solutions, including fan-only, fan-conventional heat sink (HS), or fan-conventional HS-heat pipe (HP) integrated systems, face penalties such as noise, dust accumulation, high electricity usage, space constraints, and thermal limitations of the working fluid. While thermoelectric coolers (TEC) have advantages like compactness and noise-free operation, they alone are insufficient for cooling sophisticated chips; combining them with microchannel heat sinks (MCHS) and superior fluid is crucial for achieving faster and more efficient cooling. Considering previous studies involving TECs used alone, with conventional fluids integrated into MCHS, and with a mono-nanofluid integrated into MCHSs, this is the first study to consider a TEC integrated with two MCHSs and to use a ZnO-TiO2/water hybrid nanofluid to maximize the performance of this miniature refrigeration system. Accordingly, an experimental study was carried out on the aforementioned refrigeration system using various concentrations (φ) of ZnO-TiO2/water hybrid nanofluid for different flow rates, utilizing both conventional heat transfer and the TEC’s mathematical operating principle. The results were interpreted via Reynolds number, Prandtl number, heat transfer rate, Nusselt number, total thermal resistance, and coefficient of performance (COP). The increase in φ from 0% to 0.03%, accompanied by a decrease in flow rate from 16 × 10−5 m3/s to 9 × 10−5 m3/s, increased the heat transfer rate for the heat-absorbing and the heat-emitting sides of the refrigeration system from 19.510 W to 45.794 W, and 13.639 W to 22.406 W, respectively. The experimental COP for pure water was 0.325 at the lowest volume flow rate, but increased to 0.934 at a φ of 0.030%. Considering the thermal characteristics, this study demonstrates that the proposed system is particularly advantageous at low flow rates and high φ, making it a potential candidate for electronic circuit cooling. Considerations such as investigating certain material properties to allow for further improvement of the proposed system were offered.

Averaged Heat Fluxes Densities During Condensation and Evaporation of a Water Droplet

This study is intended for experimental investigation of the influence of boundary conditions on the intensity of phase transformations and heat transfer processes in a suspended water droplet. The results of the dynamics of the averaged heat fluxes densities during the droplet phase change cycle are presented and analysed. The influence of the droplet initial temperature, the surrounding air flow temperature and the additional humidity in the air flow were defined in separate regimes of the droplet phase transformations cycle. The experiments performed demonstrated that the parameters of the air flow surrounding the suspended water droplet affect the intensity of heat fluxes in the droplet throughout whole its phase change cycle. It was experimentally claimed that the initial temperature of the water droplet has no influence on the droplet heat and mass transfer processes in the equilibrium evaporation regime. The obtained results showed that most intensity heat flux densities are at the beginning of the droplet phase change cycle when condensation process occurs on the droplet’s surface in case with biggest amount of additional humidity in the surrounding air flow. This is very important in technologies of cleaning and heat recovery from flue gases.

The Influence of the Heat Transfer Mode on the Stability of Foam Extinguishing Agents

The mass loss mechanisms of an aqueous film-forming foam (AF foam), an AR/AFFF water-soluble film-forming foam extinguishing agent (AR foam), and a Class A foam extinguishing agent (A foam) at different levels of thermal radiation, thermal convection, and heat conduction intensity were studied. At a relatively low thermal radiation intensity, the liquid separation rate of the AF, AR, and A foams is related to the properties of the foam itself, such as viscosity and surface/interface tension, which are relatively independent of the external radiation heat flux of the foam. At low radiation intensity (15 kW/m2 and 25 kW/m2), the liquid separation rate of the AF and A foams is relatively stable. When the heat flux intensity is 35 kW/m2, the liquid separation rate of the AF and A foams increases notably, which may be mainly due to the rapid decrease in foam viscosity. And the mass loss behavior is dominated by liquid separation in the AF, AR, and A foams under the influence of thermal radiation and thermal convection. Under the same experimental conditions, the liquid separation rate of AF is the fastest. There is no significant difference in the evaporation rates of the three kinds of foam in the same heat conduction condition. In addition, the AR and A foams usually have a 25% longer liquid separation time (t) under thermal radiation and thermal convection, and the thermal stability is better than AF foam. The temperature reached by the AF foam layer under thermal convection was lower than that of the AR and A foams, and the time for the foam layer to reach the highest temperature under heat conduction was longer than that of the AR and A foams.

Green synthesized clove-treated carbon nanotubes/titanium dioxide hybrid nanofluids for enhancing flat-plate solar collector performance

Green synthesizing carbon-based hybrid nanofluids has the potential to drive innovation in both renewable energy technologies and nanomaterial applications. In this regard, the current experimental work focuses on enhancing the thermal performance of flat-plate solar collectors (FPSCs) using working fluids made of nanocomposite materials via an eco-friendly technique (clove). Conventional methods of synthesizing nanofluids frequently involve using hazardous chemicals, raising concerns about the environment and human health. This experimental work examined the energy efficiency, exergy efficiency, and hydrothermal performance of FPSC using clove-treated carbon nanotubes/titanium dioxide (CT-MWCNTs/TiO2) nanocomposites by the ratio of (60 % to 40 %) dispersed in distilled water (DW). The test conditions were in the following ranges: hybrid nanofluid in different weight concentrations (0.025, 0.05, 0.075, and 0.1 wt%), different flow rates (0.3, 0.6, 0.9, and 1.2 L/min), heat flux intensities (400, 600, 800, and 1000 W/m2) and inlet temperature (30, 35, 40, 45 °C). The experimental results revealed that, the maximum enhancement in the energy efficiency (20.6 %) and exergy efficiency (22.9 %) were achieved at 0.1 wt% and 1.2 L/min, relative to the base fluid. In addition, the solar collector size was reduced by 20.5 % due to using a hybrid nanofluid. To conclude, the hybrid nanofluid outperformed the mono nanofluids regarding overall thermal evaluations. The novel hybrid nanofluids generally showed promising results for managing and conserving energy applications.

High temperature and fire properties of sustainable syntactic foam reinforced by end‐of‐life tyre‐derived rubber particles

AbstractThe management of end‐of‐life tyres faces challenges due to insufficient recycling infrastructure and technologies, as well as limited markets for the materials recovered from them. To mitigate this, waste rubber can be upcycled and used as filler material for polymer matrix composites. Before rubber‐reinforced composites can be certified for fire‐prone applications, their thermal and flammability properties must be understood. This research investigates the effect of rubber fillers on the thermal stability, flammability and flame spread characteristics of epoxy matrix syntactic foam. Thermogravimetric analysis, Fourier Transform Infrared spectrometry (FTIR), scanning electron microscopy and attenuated total reflection FTIR spectrometry were employed to elucidate changes in thermal degradation behaviours. The influence of rubber fillers on the flammability of syntactic foam was assessed using the cone calorimeter. The fire reaction properties of rubber‐reinforced foam were affected by the intensity of the incident heat flux. Regardless of the incident heat flux, an increase in rubber content led to higher total heat release. At the lower heat flux of 35 kW/m2, the fire growth rate increased with rubber content, but at the higher heat flux of 50 kW/m2, the fire growth rate decreased as the rubber content increased. Importantly, all rubber‐reinforced syntactic foams achieved a UL94 HB ranking and exhibited reduced flame spread rates compared to the unmodified foam. This study demonstrated the potential for upcycling waste rubber into sustainable engineering products and expanded the knowledge base on fire reaction properties and flame spread characteristics of such hybrid composite materials.

Experimental evaluation of the concentrated solar heat flux distribution provided by an 8 m[formula omitted] Scheffler reflector

This study gives experimental results on the intensity and distribution of the concentrated heat flux delivered by an 8m2 Scheffler reflector located in Marseille, France (lon. 5.4° E, lat. 43.3° N). Using thermography and inverse techniques, detailed maps of heat flux densities on a vertical screen were obtained at different times and on different days. The heat flux distributions provided were successfully fitted to a two-dimensional Gaussian model. The model parameters were used to objectively calculate, among other things, the mean major and minor diameters of the ellipse containing 99.7% of the heat flux, i.e. 45cm and 37cm respectively. Maximum heat flux densities ranged between 81kWm−2 and 112kWm−2 and the total heat fluxes delivered by the reflector were between 2.4kW and 3.2kW, which led to energy efficiencies between 61% and 67%. The issue of repeatability of measurements and seasonal/daily variations is also discussed. The results of this study could serve as a basis for the development of realistic numerical models and be useful to engineers responsible for optimising systems incorporating a Scheffler reflector.

A novel non-destructive acoustic approach for investigating pool boiling phenomena

Analyzing boiling phenomena and performance within invisible boiling systems, where the interior cannot be observed, has traditionally been challenging. In this study, we propose a non-destructive approach using acoustic analysis method to figure out the boiling dynamics or performance, non-invasively. In pool boiling experiment, the acoustic emission (AE) sensor captured the emitted signals at the outside of the heater. Our analysis focused on two key aspects: single bubble characterization and multi-boiling phenomena. For single bubble, we observed that the AE signals originated from the pressure waves generated at the solid-vapor interface of the bubbles. Utilizing a finite difference method, the bubble radius was reverse calculated from the AE signals, enabling predictions up to a certain duration. Frequency analysis revealed a direct correlation between the signal frequency and the oscillation of the bubble radius. In multi-boiling phenomena, as heat flux increases, the number and intensity of AE signals rise, indicating more frequent and rapid bubble generation. A correlation was established between the AE signal counts in the 40 kHz range and the heat transfer coefficient (HTC). The AE count increased linearly with heat flux until it saturated near the critical heat flux. This correlation provided the non-destructive method to estimate the boiling HTC based on AE measurements. In conclusion, the findings offer insights into bubble dynamics, heat transfer characteristics, and the potential application for HTC estimation.

Калориметрия фазовых переходов «ферромагнетик ↔ парамагнетик» в железе, кобальте, никеле

There are some special features in calorimetry signal introduced by the ferromagnetic ↔ paramagnetic phase transitions in magnetic materials. The purpose of this study was to investigate, by means of high-resolution differential scanning calorimetry, the effects of heat flux change during direct and reverse second-order phase transformations of the type ferromagnetic ↔ paramagnetic in some high-purity metals possessing natural ferromagnetism: iron, cobalt, and nickel. The literature review indicates that so far there has been no research describing such phase transitions with the help of differential scanning calorimetry. Our study detected anomalies in the dependences of heat flux intensity on temperature. There was noted a shift to the region of higher temperatures during heating in the range of thermocycling rates of 5-10-20-40 K/min. A shift to the region of lower temperatures during cooling in the same range of thermocycling rates was observed in the area of registration of second-order phase transition. The possibility of using calorimetric measurements for estimating the Curie temperature at ferromagnetic ↔ paramagnetic transitions in the metals is shown. The authors highlight that, when conducting high-resolution calorimetric measurements, it is essential to take into consideration in the total heat flux balance the possible contribution from the effects associated with second-order phase transitions, including, in particular, ferromagnetic ↔ paramagnetic transitions.

Test conditions influence on thermal conductivity and contact conductance of sand at transient state

The proper assessment of soil thermal properties, such as thermal conductivity, assumes a particular relevance for the design of Ground Source Heat Pump systems, as it determines the heat transfer and the energy efficiency design. Multiple methods can be used for thermal conductivity estimation, however significant scatters in measurements are often reported when using different (or even the same) methods. This work presents a detailed study of the thermal conductivity and the thermal contact conductance of a reference sand tested in transient conditions, analyzing the effect of several factors, such as the heating time, degree of saturation, soil density, temperature and heat flux intensity, on thermal conductivity measurements for dry state or fully saturated conditions. To avoid measurement errors and heterogeneity effects, only three samples were prepared with different compaction ratios, and systematically tested in dry and fully saturated conditions, under different control variables (temperature, testing time, and injected heat flux). Two analytical methods based on the line source solution were used to estimate soil thermal conductivity and to assess the probe-to-soil thermal contact conductance. Significant relationships were obtained between thermal conductivity and soil state conditions and testing variables, highlighting that a heating time longer than the one usually recommended in the standards is clearly needed. Finally, this study uses measured temperature values to determine the probe-to-soil thermal contact conductance, indicating its relevance in soil thermal conductivity estimation.

Numerical modeling of heat conduction in bodies with cracks

All structural materials contain certain microdefects. Various elements of aircraft and spacecraft made from these materials are subjected to high mechanical loads and thermal effects during operation, which, in turn, can lead to the evolution of defects and total fracture of individual parts of the mechanism. Therefore, a quantitative and qualitative estimation of the stress and temperature fields in different bodies with complex configuration of external loading and temperature disturbances is needed. This paper presents a technique for numerical modeling of the temperature field in a medium weakened by a large system of partially heat penetrable cracks, including the possibility of considering it as an infinite periodic system. The method is based on a numerical algorithm, which uses the expansion of the solution into a finite series. Every term of this series is a certain analytical solution of the heat conduction theory obtained by the authors. To verify the method, the numerical results were compared with the well-known analytical solutions both for a configuration with finite number of cracks and for the periodic system. Also the heat flux intensity factors for a doubly periodic system were determined.

Application of PEG-Fe3O4 nanofluid in flat-plate solar collector: An experimental investigation

In the present study, novel in-situ oxidation precipitation of ferrous hydroxide method is used to synthesized Fe3O4 nanoparticles and Polyethylene glycol 200 is used for covalent functionalization. Various characterizations tests (FESEM, EDX, XRD, FTIR, HRTEM) were performed, and the Polyethylene glycol treated Iron oxides functionalization was confirmed. Thermal conductivity, density, specific heat, and viscosity were experimentally assessed and validated using the correlations that were available. The corresponding improvements in thermophysical characteristics were 13.35%, 0.06%, 0.37%, and 20.9% at 0.1 wt% and 35°C. UV–vis spectroscopy and Zeta protentional was used to check the stability of nanofluids and found that nanofluid was stable for 30 days. A flat plate solar collector was experimentally installed, and the thermal performance of collector was calculated using ferrofluid under ASHRAE standard 93–2003 at different heat flux intensities (597,775,988 W/m2), mass flow rates ((0.0133, 0.0200, 0.0266 kg/s), inlet fluid temperature (30–50°C) and weight concentrations (0.025,0.05,0.075,0.1%). The highest thermal efficiency enhancement of 13.83% was noticed. Moreover, the ANSYS-CFD model was used for the numerical analysis of the thermal performance of flat plate collector at the same environmental conditions, and a maximum difference of 8.33% at 0.1 wt% was noticed in comparison with experimental data.