Thermophysical Properties Of Fluids Research Articles

Effects of thermal boundary conditions on Stokes' second problem

In this investigation, an infinite flat plate is employed to examine the flow behavior of Casson fluid and the associated heat transfer phenomena. The plate undergoes an initial acceleration with a constant velocity until it eventually decelerates to rest. The energy equation incorporates the effects of viscous dissipation. An appropriate similarity transformation transforms the governing equations into coupled nonlinear ordinary differential equations (ODEs). A closed-form solution for the velocity profile is obtained, while the energy equation is solved using the built-in function NDSOLVE in Mathematica. The study investigates the influence of governing parameters on dimensionless velocity, temperature, skin friction, and local heat transfer rate under two thermal boundary conditions: Newtonian heating and convective boundary conditions. The fluid's thermophysical properties remain constant throughout the study, with the surface temperature of the plate assumed to be fixed at a constant value. A graphical analysis examines the flow behavior and temperature distribution, revealing the impact of non-dimensional parameters. This study reveals that thermal boundary conditions significantly influence heat transfer rates, with Newtonian heating leading to an increase and convective heating causing a decrease. This is attributed to the direct application of heat at the boundary in Newtonian heating, which enhances thermal energy transfer. In contrast, convective heating disperses heat through fluid motion, limiting transfer rates.

Wall Heat Transfer Characteristic of Parallel-plate Channel Filled with Open-cell Metal Foams in Large Flow Velocity Range

Abstract High porosity open-cell metal foams can be utilized to fill parallel-plate channels for achieving efficient cooling performance. A wall heat transfer model considering viscous and inertial heat effects is given based on local thermal non-equilibrium theory. Detailed investigations are conducted on influences of parameters on cooling performance. The results indicate that an optimum velocity exists; impacts of porosity and pore size varies with thermophysical properties of fluids and flow velocity; heat transfer resistance also depends on them; increasing foam thickness enhances cooling performance for air under identical velocities but has negligible effect for water; under identical flow rates, decreasing foam thickness improves cooling performance; enlarging base surface area is an effective approach at low flow velocities.

Wet-to-dry transition description in the mixture of working fluids

The organic rankine cycle performance and some similar processes depend on many factors. One of them is the category of the working fluid, influencing the performance through the phase/phases during and at the end of the expansion process. Droplet formation for wet fluids and superheated for dry fluids motivated the researchers to seek isentropic working fluids, where expansion could proceed and terminate in a saturated vapour state. The shape of the T-s diagram is a material property; it cannot be changed for real pure fluids, but small jumps can be initiated by replacing one working fluid with a chemically very similar one, like Propane (a wet one) with Butane (a dry one). Our study presents a much smoother transition, using mixed working fluids prepared from chemically similar materials to obtain almost ideal zeotropic mixtures. The main point of our study is to show the wet-to-dry transition for mixtures and prove or disprove the existence of compositions where the fluid can show T-s diagram resembling the ones for ideal isentropic working fluids. For this purpose, Propane was mixed with other alkanes, such as Butane, Pentane, and Hexane, in various compositions, and the thermophysical properties of fluids were calculated by using the REFPROP software program. Wet-to-dry transitions were shown for the Propane/Hexane mixture at (0.6584 + 0.3416 mass fraction), while (0.5823 + 0.4177 mass fraction) and (0.6436 + 0.3564 mass fraction) was the transition mixture for Propane/Butane and Propane/Pentane respectively. Consequently, when exceeding the mentioned composition range, the fluids switch from wet to dry without forming a composition showing ideal isentropic properties. Therefore, isentropic working fluid (showing an infinite slope for the saturated vapour branch in a finite, nonzero temperature range) was not found during this transition.

Investigation on unsteady characteristics of flow separation in a supercritical carbon dioxide centrifugal compressor

As one of the core components of supercritical carbon dioxide (S-CO2) closed Brayton cycle, the efficiency of S-CO2 centrifugal compressor plays a crucial role. Affected by the special thermophysical properties of S-CO2 fluid, the flow mechanism of S-CO2 centrifugal compressor is different from the centrifugal compressor of conventional fluid, such as air. Previous studies have found that the flow separation within the flow domain of this kind of compressor is easily to occur downstream the pressure surface. Many steady computational fluid dynamics (CFD) studies have been conducted on the S-CO2 centrifugal compressors, but few studies focused on the unsteady evolution of this flow separation. In this paper, the unsteady CFD simulation is carried out in the flow passage of a S-CO2 centrifugal compressor. The solution domain of CFD simulation includes compressor blades, diffuser and volute. The performance and the unsteady flow behavior of S-CO2 centrifugal compressor is obtained. Under low flow rate conditions, the flow separation on the pressure surface of the blade of S-CO2 centrifugal compressor is more likely to occur, causing the decrease of compressor performance. This flow separation has strong unsteady characteristics, which deteriorates several times during a rotation cycle, meanwhile the vortex shedding happens. At the time steps of vortex shedding, the pressure near the trailing edge of the impeller fluctuates greatly, indicating that this unsteady flow separation brings a large flow loss to the S-CO2 centrifugal compressor.

THE EFFECTS OF SHAPE AND LIQUID PROPERTIES ON PRESSURE SWIRL ATOMIZER IN-NOZZLE FLOW

The internal flow in pressure swirl atomizers is numerically predicted by performing large eddy simulations and using a volume of fluid approach. The output of the numerical model is validated by comparing it with three databases of experimental measurements obtained on large-scale pressure swirl atomizers available in the open literature. A simplified analytical model previously developed by the authors, which relates the swirl intensity to the thickness of the fluid exiting the nozzle, is used to analyze the flow behavior in three pressure swirl atomizers, with large differences in the injector geometry, the operating conditions, and the fluid thermophysical properties. This simple relationship is found to hold for the three pressure swirl atomizers, with small changes of the parameter that accounts for energy losses, while data obtained with relatively small variations of the injector geometry are found to collapse on the same curve. The effects of operating conditions and fluid thermophysical properties on this relation are found to be irrelevant.

CALCULATION OF TECHNOLOGY ALGORITHM AND SUCCESSFUL APPLICATION OF THERMOCHEMICAL METHOD DURING WELL WORKOVER

This article is devoted to the analysis of the success of the thermochemical method of generating and transferring thermal energy for underground workover technologies of producing wells. In order to justify the design and consumption of reagents, an algorithm and calculator were compiled based on the well design and thermophysical properties of consumables and fluids: heat capacity of steel, water, ice, enthalpy of ice melting and chemical reaction, the length of the paraffin hydrate plug interval.Thermophysical calculations have shown that for a well with a diameter of 146 and a 73 mm tubing lift, 153 kg of fuel reagent is required for thermal destruction of a paraffin hydrate plug 100 meters long. Based on the geometry of the candidate well and the expected intervals of waxhydrate plug formation, reagent consumption is determined, and a design and work plan are drawn up. The algorithm makes it possible to calculate the flow rate and concentration of working solutions of reagents in order to reach the target temperature at the thermal exposure interval.Measurements of the deep thermometer made it possible to determine that the selected composition of reagents and the exothermic reaction with a delay in heat generation allow to achieve a loss of heat to dissipation at the level of 17 % by 2500 meters of the tubing elevator.The technology of thermal destruction of paraffin-hydrate plugs in gascondensate wells was implemented at the East-Tarkosalinskoye oil and gas condensate field and the Komsomolskoye field with achievement of the specified success criteria.Technologies for development and removal of water from the bottomhole of gas and gas-condensate wells ensure formation of a gas-liquid mixture and removal of water from the bottomhole at the wellhead. The technologies were used at the production facilities of the Vuktyl field (Komi Republic), Amangeldygaz (Kazakhstan Republic), and the East-Tarkosalinsky field (Yamalo-Nenets Autonomous Okrug). As a result of water development, gas wells are switched from pulsating to permanent operation. Heat (thermal) treatment of producing wells uses injection of heat and nitrogen-generating solutions with transfer of thermochemical energy of reagents through permafrost and low-temperature intervals with minimal heat losses. The efficiency of the heat transfer technology was confirmed by temperature measurement by downhole sensors at 139–147 °C at development facilities with reservoir temperatures of 41–43 °C (Ural-Volga region, Purovsky region).The technology of restoring the productivity of gas and gas condensate wells using aerated acids makes it possible to increase the success of subsequent development. The use of the technology of foam acid treatment with methanol makes it possible to successfully restore the productivity of gas and gas condensate wells prone to water removal. Aeration and heating of process solutions of reagents makes it possible to carry out comprehensive measures for treatment of the bottomhole zone of the well with acid and thermochemical impact.

Farklı Isı ve Basınç Koşulları Altında Düz Bir Boru İçin Tek Yönlü Akışkan-Yapı Etkileşimleri Analizi

Numerical studies on stress, deformation, and damages due to fluid flow have been highly carried out using Fluid-Structure Interaction (FSI) in recent years. FSI is highly efficient in investigating a solid domain deformed by the fluid flow. In this study, a one-way fluid-structure interaction study is performed by a straight pipe under different pressure and thermal conditions. Here, the thermophysical properties of the fluid and mechanical properties of the solid domain can be subjected to change during fluid flow. An aluminum straight pipe with a 1 mm wall thickness is operated under 1 Bar, 5 Bar, and 10 Bar with three different surface temperatures -10ºC, 20ºC, and 50ºC. This study aims to investigate the structural variation of aluminum by the temperature and pressure change of operating fluid in the pipe. Variation of thermophysical properties of fluid by heated pipe surface is integrated into the numerical analysis by generated functions. Numerical analysis showed that the variation of temperature in operating fluid highly affects the fluid characteristic and the structural response of the solid domain by different temperatures. An increase in the operating pressure caused maximum deformation to approximately %100 from 1 Bar to 5 Bar, and approximately %120 from 1 Bar to 10 Bar for the adiabatic process as expected but in the heating conditions stress is nearly three times higher than cooling conditions. As a result, one-way FSI solutions are highly effective in investigating the deformed solid domain as a result of flow, thermal, and operating conditions.

Effects of buoyancy in a laminar flow of supercritical carbon dioxide in a horizontal microchannel at different gravities

The effects of buoyancy were generally neglected in convective heat transfer inside horizontal microchannels because gravitational effects diminish compared to inertial and viscous forces with diminishing length scale. However, buoyancy effects can be significant for supercritical carbon dioxide (sCO2) slightly above the critical condition in microchannels, and the heat transfer coefficient can peak because of abrupt changes in the fluid's thermophysical properties. Previous studies considered buoyancy in channels with hydraulic diameter above 500 μm at a constant surface heat flux boundary condition. These effects were not well understood for microchannels with a hydraulic diameter as small as 100 μm, particularly with constant wall temperature boundary condition, but they hold great potential in the design of micro heat exchangers.This study numerically investigated the effects of buoyancy inside a 100-μm hydraulic diameter square microchannel with a total length of 27 mm and a heated length of 25 mm for laminar flow of sCO2. A total of 180 cases were analyzed to predict the effects of surface temperature ranging from 310 to 350 K, pressure ranging from 8 to 10 MPa, Reynolds numbers from 100 to 500, and gravitational acceleration from 0 g to 3 g, on the heat transfer. It was revealed that gravity has a significant effect on the heat transfer coefficient and on the thermal entrance length. The average heat transfer coefficient was increased by up to 138% on the bottom surface of the channel for 3 g compared to 0 g. The thermal entrance length showed a mixed behavior, such as it was increased for certain conditions while decreased for other conditions. For some cases, it was also observed that the pressure drop increased slightly with increasing gravity, and it was directly proportional to the wall shear stress. Finally, it was concluded that the gravity had a significant effect on the flow and heat transfer characteristics but was negligible for Richardson number below 10−4.

Development of models for green hydrogen production of Turkey geothermal Resources: A case study demonstration of thermodynamics and thermoeconomics analyses

The transition to sustainable and clean energy sources has become imperative in the face of global climate change concerns. Hydrogen is a versatile and environmentally friendly energy carrier among the potential solutions. Utilizing renewable resources for hydrogen production is a promising avenue, and Turkey's geothermal resources offer significant potential. This study focuses on developing models for assessing Turkey's geothermal resources' green hydrogen production potential, employing thermodynamics and thermoeconomics analyses. The thermodynamic analysis explores the thermophysical properties of geothermal fluids, investigating the feasibility of utilizing the available heat for hydrogen production through electrolysis. As a result of the performance analysis, the Afyon Geothermal Power Plant (AFJES) produces 4132 kW net power with 150 kg/s geo-fluid at 110℃. The unit costs of the electricity and hydrogen produced in the power plant are 0.01671 $/kWh and 1.684 $/kg, respectively. The study aims to determine the optimal conditions and configurations for efficient hydrogen production from Turkey's geothermal resources. The findings provide valuable insights for policymakers, investors, and energy stakeholders, aiding in the decision-making process for deploying sustainable and economically viable hydrogen production in Turkey's geothermal-rich regions. Furthermore, this research contributes to the broader objective of achieving a low-carbon energy future while tapping into the immense potential of geothermal resources.

THE EFFECT OF THERMOPHYSIZAL PROPERTIES OF FLUIDS ON CONVECTIVE HEAT TRANSFER IN ELECTRONIC DEVICES

The impact of enclosure aspect ratio and different thermophysical properties of fluids on heat transfer were investigated in rectangular enclosure with 3x3 array of flush-mounted chips placed on the front vertical wall with constant temperature and cooled by the opposite wall. To study heat transfer inside the enclosure simulations were done for four enclosure aspect ratios(A=1.0, 5.0, 7.5, 20.0) and five fluids(air, water, FC-40, FC-72, FC-88). Numerical results show that the highest velocities are in the air while low velocities have been noticed in the water, FC-40, FC-72, FC-88. The maximum air velocities for the W component are obtained precisely at a height of Z= 5.5. It is observed that when enclosure aspect ratio decreases, the fluid velocity increases. Maximum Nu number was when enclosure was filled with dielectric fluids FC-72 and FC-88, and minimal was found in the air. To ensure that chosen numerical methods, computer program was implemented correctly test task were completed. Good agreement is found between the results.

Experimental analysis of thermal performance of direct absorption parabolic trough collector integrating water based nanofluids for sustainable environment applications

Integration of nanofluids with solar collectors to enhance collector's thermal performance stands out as one of the most effective techniques owning to nanofluids favorable thermo-physical properties. By improving the thermo-physical properties of heat transfer fluids, nanofluids enhance the efficiency of thermal systems by improving the thermal energy storage capacity. This experimental study serves as a novel comparison between water-based Al2O3 (Alumina) and Multi-walled Carbon Nanotubes (MWCNTs) nanofluids in such mass concentrations (0.1%, 0.2%, and 0.3%) at fixed mass flow rates of 0.012 kg/s and 0.024 kg/s to investigate the impact on the performance of Direct Absorption Parabolic Trough Collectors (DAPTC) under the arid climatic conditions of Pakistan. The peak thermal efficiencies were found to be 40%, 56% and 58% for distilled water (DW), Al2O3-water and CNTs-water nanofluids, respectively. Thermal efficiency of DAPTC was improved by 18% in comparison with the basefluid alone on account of increased surface area, thermal conductivity and overall heat transfer capabilities. The CNTs-water nanofluids were observed to be more thermal efficient Heat Transfer Fluids (HTFs) owing to the black color and comparatively lower specific heat capacity. These thermal efficient fluids are of great use in the thermal energy storage systems. In addition, the use of nanofluids for heating and cooling purposes in industries is preferable as operational and manufacturing costs can also be lowered by reducing the systems size.

Prediction of the temperature distribution in the reservoir when oil is displaced by a fluid with a temperature different from the reservoir

The temperature field is an important factor that must be considered when using thermal methods to intensify oil production. The change in the temperature field is accompanied by a change in the thermophysical properties of reservoir fluids and the entire bottom-hole zone. For example, changes in fluid viscosity, phase transformations or paraffin deposition. The prediction of the thermal field in the reservoir during fluid injection with a temperature other than the reservoir is an important and actual task. All the processes described above are based on the prediction of the temperature field and its evolution. Non-isothermal filtration models embedded in expensive commercial simulators are used to analyze the thermal field in formations, which allow calculating its detailed evolution in geologically complex deposits. However, many tasks are reduced to determining the probability of activation of a particular thermal process in the reservoir. Therefore, the purpose of this work is to develop a simplified model of the evolution of the thermal field in the reservoir during fluid injection with a temperature different from the reservoir. In this paper, the stationary problem of the distribution of fluid temperature in the injection well trunk is solved. An algorithm for determining the heat transfer coefficient by measuring the temperature at the bottom of the well has been developed. A simplified model of the formation of a temperature field in a reservoir during the injection of a fluid with a temperature different from the reservoir in the Lauwerier approximation is formulated. The formula for determining the average value of the heat transfer coefficient along the entire length of the formation is obtained. It is shown that the heat transfer coefficient depends on the thermophysical properties of the injected fluid and the parameters of the injection well operation. It is shown that the absence of measurements of the thermophysical properties of rocks and reservoir fluids leads to predictions of the thermal field with maximum uncertainty in the half of the impact site closest to the injection well.

Determination of Hydrogen’s Thermophysical Properties Using a Statistical Thermodynamic Method

Accurate determination of the thermophysical properties of hydrogen is a crucial issue in hydrogen system design. By developing computational programs, a statistical thermodynamic model based on fundamental equations of state was implemented to determine hydrogen’s thermophysical properties, including the ortho-hydrogen fraction in equilibrium hydrogen, para-ortho hydrogen conversion heat, isobaric heat capacities and enthalpies. The deviations of calculated para-hydrogen enthalpies from REFPROP data were within 2.22%, ranging from 20 K to 300K at 0.1 MPa, and within 2.32% between 100 K and 1500 K at pressures from 0.1 MPa to 20 MPa. To quantitatively assess the convenience of the statistical thermodynamic method, the running speeds of programs with different methods for determining hydrogen’s thermophysical properties were compared. The time required for statistical thermodynamic calculation was 7.95% that required for treading REFPROP data when the performance of the variable density multilayer insulation combined with a one vapor-cooled shield and para-ortho hydrogen conversion was calculated. The programs developed based on the statistical thermodynamic method can be used to determine the thermophysical properties of hydrogen or other fluids.

Onset of Viscous Dissipation Instability in Plane Couette Flow with Temperature-Dependent Viscosity

The conditions for the onset of dissipation thermal instability with temperature-dependent viscosity in the plane Couette flow of a Newtonian fluid are analyzed. The studied system consists of a horizontal fluid layer confined between an adiabatic (fixed) lower wall and an isothermal (moving) upper wall. Both the exponential and the linear fluidity models are considered in order to account for the thermodependency of the fluid’s viscosity. The linear stability analysis of the base solution with respect to arbitrarily oriented normal modes is carried out numerically by employing a shooting method. The most unstable disturbances are proven to be stationary longitudinal rolls, and their stability is governed by three dimensionless parameters: the viscous dissipation Rayleigh number, Prandtl number and a parameter that represents the variability of the viscosity with temperature. It is shown that the effect of the variation of the viscosity is to promote the stability of the base flow. As expected, the two viscosity models’ results diverge as the variability of the viscosity increases, and the exponential model is found to be more stable than the linear fluidity one. By considering the thermophysical properties of real fluids, it is shown that viscous dissipation thermal instability precedes hydrodynamic instability. An energy budget analysis is proposed to better understand both the stabilization effect of the thermal variability of the viscosity and differences with viscous dissipation hydrodynamic instability.

Development of thermodynamically consistent machine-learning equations of state: Application to the Mie fluid.

A procedure for deriving thermodynamically consistent data-driven equations of state (EoS) for fluids is presented. The method is based on fitting the Helmholtz free energy using artificial neural networks to obtain a closed-form relationship between the thermophysical properties of fluids (FE-ANN EoS). As a proof-of-concept, an FE-ANN EoS is developed for the Mie fluids, starting from a database obtained by classical molecular dynamics simulations. The FE-ANN EoS is trained using first- (pressure and internal energy) and second-order (e.g., heat capacities, Joule-Thomson coefficients) derivative data. Additional constraints ensure that the data-driven model fulfills thermodynamically consistent limits and behavior. The results for the FE-ANN EoS are shown to be as accurate as the best available analytical model while being developed in a fraction of the time. The robustness of the "digital" equation of state is exemplified by computing physical behavior it has not been trained on, for example, fluid phase equilibria. Furthermore, the model's internal consistency is successfully assessed using Brown's characteristic curves.

PVT behaviour of hydrophilic and hydrophobic eutectic solvents

Among the basic principles of green chemistry is the search for less harmful alternative solvents than conventional solvents. Knowing the thermophysical properties of fluids under different pressure and temperature conditions is essential to propose them. Herein, we present data on the densities at several pressures (from 0.1 to 65 MPa) and temperatures (from 283.15 to 338.15 K) of two deep eutectic solvents with hydrophilic characteristics (choline chloride + ethylene glycol or glycerol) and two eutectic solvents with hydrophobic characteristics (camphor + thymol or menthol). We used the Tait equation of state to correlate and calculate derived properties. Moreover, we modelled the mixtures with the PC-SAFT equation of state. The results showed that the hydrophilic solvents were more compact than the hydrophobic ones. The former exhibited an abnormal thermal behaviour of the isobaric thermal expansibility. The deviations in the correlation of densities with the thermodynamic model were between 0.5 and 3%. They were lower for the mixtures with weaker interactions.

Turbulent natural convection heat transfer enhancement of nanofluids

This study investigates the enhancement of heat transfer for the fluid with the addition of nano-particles in a two-dimensional rectangular cavity. Thermo-physical properties of such fluids and volume fraction of nano-particles in those fluids and its heat transfer characteristics are studied. ANSYS Fluent code is utilized for this purpose. Validation of the computational model has been carried out against the benchmark data available from the literature. A heat transfer correlation in terms of the Nusselt number (Nu) average as a function of Grashoff number and volume fraction of the nano-particles in the base fluid for the turbulent flow is developed and formulated in this study.

Numerical Investigation of Conjugate Heat Transfer and Natural Convection Using the Lattice-Boltzmann Method for Realistic Thermophysical Properties

To enable the lattice-Boltzmann method (LBM) to account for temporally constant but spatially varying thermophysical properties, modifications must be made. Recently, many methods have emerged that can account for conjugate heat transfer (CHT). However, there still is a lack of information on the possible physical property range regarding realistic properties. Therefore, two test cases were investigated to gain further insight. First, a differentially heated cavity filled with blocks was used to investigate the influence of CHT on the error and stability of the LBM simulations. Reference finite volume method (FVM) simulations were carried out to estimate the error. It was found that a range between 0.5 to 1.5 is recommended for the fluid relaxation time to balance computational effort, stability, and accuracy. In addition, realistic thermophysical properties of fluids and solids were selected to test whether the lattice-Boltzmann method is suitable for simulating relevant industry-related applications. For a stable simulation, a mesh with 64 times more lattices was needed for the most extreme test case. The second test case was an insulated cavity with a heating pad as the local heat source, which was investigated in terms of the accuracy of a transient simulation and compared to a FVM simulation. It was found that the fluid-phase relaxation time mainly determines the error and that large thermal relaxation times for the solid improve accuracy. Observed deviations from the FVM reference simulations ranged from approximately 20% to below 1%, depending on collision operator and combination of relaxation times. For processes with a large temperature spread, the temporally constant thermophysical properties of the LBM are the primary constraint.

Conjugate-Based Numerical Analysis of Parabolic Trough Receiver Pipe With Temperature-Dependent Thermo-Physical Properties of Heat Transfer Fluid Under Laminar Flow Regime

Abstract In this article, the use of gas as a working fluid in the parabolic trough receiver (PTR) has been investigated numerically. The present study aims to determine which gas will work best as a heat transfer fluid (HTF) by analyzing the impact of several gases on the PTR’s performance. So, gases, such as carbon dioxide, helium, nitrogen, oxygen, hydrogen, methane, neon, and air, are considered in the present study, which flow through a thick-wall stainless steel pipe under a laminar flow regime. The temperature-dependent thermo-physical properties of the gas are considered. The finite difference method (FDM) with the harmonic mean technique is employed to solve this conjugate heat transfer problem. The current research findings are verified with those reported in the literature and are in excellent agreement. The grid-independent study is conducted to choose the optimal grid size. After that, the multi-objective function optimization technique and performance enhancement factor (PEF) is used to select the best suitable HTF, and it found that hydrogen gas is most appropriate based on these two criteria. Then, the influence of various parametric studies such as Reynolds number, solar flux, and receiver pipe thickness on the Nusselt number has been carried out. It is found that the Nusselt number increases with the Reynolds number while it decreases with solar flux and receiver pipe thickness. The significance of the current study may aid in choosing the appropriate gas as HTF in the parabolic trough solar collector (PTSC).

Effect of nano materials for the nano fluids in solar thermal energy: A review on applications in solar collector

Sun is the prime source of energy in the universe. Solar energy is available freely and has no adverse effect on the environment like greenhouse gases, CO2 emission etc. Hence, solar energy has the significant role amongst all renewable energy sources. The conversion of solar energy into the thermal energy can be done through the flat plate solar collector. The conventional working fluids used in the solar collector has poor thermo-physical properties which lowers the efficiency of solar collector. This review throws light on the latest developments on the performance improvement of solar flat plate collector. The earlier research performed on the use of nanofluids for the performance improvement of solar flat plate collector is comprehensively presented. An extensive research indicates that improving the thermo-physical properties of conventional heat transfer fluid leads to the performance improvement of flat plate solar collector. This can be achieved by the use of nanofluid instead of conventional fluid in solar collector.