Fluid-solid Conjugate Heat Transfer Research Articles

A fast fluid–solid coupled heat transfer algorithm based on dividing the development stages of the flow field

In this study, a fast numerical method for solving the forced convection conjugate heat transfer problem was developed. The method first proposes a new dimensionless number (Fs) that represents the degree of influence of convection on the temperature field in the flow field. It delineates the stage of development of the flow field by monitoring the change in Fs to determine the moment when the flow field suspends updating and improve the computational efficiency of the transient temperature field. The accuracy of the algorithm is verified by taking the fluid–solid conjugate heat transfer under forced convection conditions as an example, which can accurately capture the changes of the flow field for a given monitoring step number of 100, and classify the flow field into E3, E4 and E5 development stages according to the judgment criteria. The results show that the higher development stages correspond to smaller levels of root mean square error (RMSE) of monitoring point temperatures within 3600 s of physical simulation time, and stages E3, E4, and E5 can reach the levels of E-2, E-3, and E-4, which are 3.4, 3.3, and 3.1 times faster than the traditional coupled calculations, respectively. The algorithm is still applicable at variable time steps, but it will require a higher number of determinations compared to a fixed step. The initial error of the quasi-steady algorithm can be reduced from the E-1 level to E-4 by choosing a higher stage of development. Finally the algorithm is tested under a variety of conditions by varying the inlet temperature and flow rate and is found to be robust to both device warming and cooling.

Numerical study of flow boiling heat transfer in a mini-channel under hyper-gravity

Gravity plays a crucial role in influencing bubble behavior and heat transfer in flow boiling, and its impact can vary significantly in aerospace settings. Therefore, this study aims to numerically investigate flow boiling heat transfer in a rectangular mini-channel under hyper-gravity conditions, specifically at 12 times the normal gravity. To accomplish this, a coupled volume-of-fluid and level set method is employed, taking into account fluid-solid conjugated heat transfer as well as a nucleus site density model derived from experimental data. By reproducing the flow pattern and heat transfer characteristics under different heat flux and flow rate conditions, the study unveils the effects of hyper-gravity on flow boiling heat transfer. When the flow rate is lower under hyper-gravity conditions, a notable phenomenon occurs wherein numerous bubbles detach from the heating wall and coalesce into a vapor film at the top of the mini-channel due to increased buoyancy. In contrast, under normal gravity, bubbles merge and slide on the heating wall, leading to the formation of a dry patch below. Consequently, hyper-gravity results in a lower wall superheat, and the disparity in average wall superheat between normal and high gravities escalates as the added heat flux rises. Notably, in the hyper-gravity environment, the frequent detachment of bubbles in the middle and downstream sections of the mini-channel leads to an initial increase in wall superheating, followed by a plateau along the flow direction. As the flow rate increases, the inertial force intensifies. However, intriguingly, the discrepancy in flow boiling heat transfer between normal and high gravities does not exhibit a monotonic decrease with the increasing flow rate. This behavior can be attributed to the pressing of more bubbles onto the heating wall under normal gravity, resulting in the formation of dry patches at high velocities.

Corrosion products deposition and its effects on conjugate heat transfer for helical cruciform fuel assembly

The corrosion products in the primary loop of the nuclear reactor can be deposited on the surface of the fuel rod, forming a deposition layer called CRUD layer, introducing the heat transfer resistance. The CRUD layer will result in an increase in the temperature of the cladding and accelerating the corrosion of the cladding. In this work, the corrosion product deposition and thermal resistance models of the deposition layer were established. The deposition behavior of corrosion products on the surface of a novel Helical-Cruciform Fuel (HCF) assembly and its influence on fluid-solid conjugate heat transfer were studied by coupling the deposition models with the flow and heat transfer models for fuel rods and coolant. The results show that the deposition rate of particles is affected by the wall shear force; the deposition rate of impurity ions is affected by the wall shear force and the temperature of the coolant in the viscous layer. The erosion rate of the deposited layer is related to the wall shear force and the sum of the particle and ion deposition rates. The thickness of CRUD layer on the surface of HCF assembly increases with the decrease of coolant flow rate and the increase of fuel power. Furthermore, the CRUD layer thickness varies in a period of 90° along the circumference of the fuel and reaches a peak at the root of the fuel ribs.

Investigation of electrohydrodynamic effects on sessile droplet evaporation using the lattice Boltzmann method

Droplet evaporation on hot substrates within an electric field plays an essential role during the electrospray cooling process. However, there is only a vague understanding of electrohydrodynamic (EHD) effects on droplet evaporation. In this paper, the coupled set of governing equations, including the Poisson equations, the energy equations, and the Navier-Stokes equations, is implemented within the lattice Boltzmann (LB) framework to examine the evaporation of leaky dielectric droplets. The contact angle hysteresis (CAH) as well as the influences of fluid-solid conjugate heat transfer are taken into consideration in this model. The method’s accuracy is validated quantitatively by using three basic cases. The results suggest that the sessile droplet could be elongated or flattened under EHD effects. When the droplet is elongated, the acceleration of the rate of evaporation is controlled by the interrelationship between thermal conduction and electric-induced convection in the droplet, i.e., the average Peclet number (Pe) value. As Pe is less than 1.0, the interior of the droplets is controlled by thermal conduction, and the applied electric field would prolong the droplet evaporation time. As Pe is greater than 2.0, the electric convection promotes evaporation compared to neutral droplets. In the case that the droplets are compressed inside the electric field, the evaporation time progressively decreases as the intensity of the electric field increases. These insights help us understand how EHD affects sessile droplet evaporation and illustrate the huge potential of electric fields for thermo-fluid manipulation.

Thermal characteristics and distribution rule of lubrication film of full ceramic ball bearing under different service condition

PurposeThe study aims to the distribution rule of lubricating oil film of full ceramic ball bearing and improve its performance and life.Design/methodology/approachThe paper established an analysis model based on the fluid–solid conjugate heat transfer theory for full ceramic ball bearings. The distribution of flow, temperature and pressure field of bearings under variable working conditions is analyzed. Meanwhile, the mathematical model of elastohydrodynamic lubrication (EHL) of full ceramic ball bearings is established. The numerical analysis is used to study the influence of variable working conditions on the lubricant film thickness and pressure distribution of bearings. The temperature rise test of full ceramic ball bearing under oil lubrication was carried out to verify the correctness of simulation results.FindingsAs the speed increased, the oil volume fraction in full ceramic ball bearing decreased and the surface pressure of rolling element increased. The temperature rise of full ceramic ball bearings increases with increasing speed and load. The lubricant film thickness of full ceramic ball bearing is positively correlated with speed and negatively correlated with load. The pressure of lubricating film is positively correlated with speed and load. The test shows that the higher inner ring speed and radial load, the higher the steady-state temperature rise of full ceramic ball bearing. The test results are in high agreement with simulation results.Originality/valueBased on the fluid–solid conjugate heat transfer theory and combined with Reynolds equation, lubricating oil film thickness formula, viscosity temperature and viscosity pressure formula. The thermal analysis model and EHL mathematical model of ceramic ball bearings are established. The flow field, temperature field and pressure field distribution of the full ceramic ball bearing are determined. And the thickness and pressure distribution of lubricating oil film in the contact area of full ceramic ball bearing were determined.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0126/

Optimal design of wavy microchannel heat sinks based on prediction and multi-objective optimization algorithm

In this paper, the multi-objective optimization of wavy microchannel heat sinks is performed by combining numerical calculation, prediction algorithm and genetic algorithm. In numerical calculation, the fluid-solid conjugate heat transfer of heat sinks with different parameters are simulated in Fluent. On this basis, the variable parameters and objective parameters are used to complete the training of neural network model, which aims to achieve accurate prediction of objective parameters. Finally, the multi-objective genetic algorithm is applied to find the Pareto front according to different requirements on the foundation of the prediction model. Results show that the coefficient of determination of the neural network models are all greater than 0.85, which proves that the prediction model has a high accuracy. The Pareto fronts are obtained by non-dominated sorting genetic algorithm (NSGA-II) with different objective parameters and they reveal that the channel with the optimal performance corresponds to a larger channel width or Reynolds number. In addition, it is also found the dimensionless temperature difference is correlated with Nusselt number.

A preliminary computational analysis towards the use of Electrically Heated Mixing Catalyst for innovative SCR after-treatment systems

This work aims at investigating the possible advantages of substituting the mixer in traditional SCR systems with an Electrically Heated Catalytic structure (EHC). First of all, EHC technology is being widely investigated in literature because it offers a concrete solution for catalyst thermal activation and film formation reduction in engine cold start conditions; however, its adoption as a mixer can also guarantee other important improvements in reducing pollutant emissions. In this work, a low-pressure injection of Ad-Blue impacts an electrically heated structure and a complete analysis of liquid droplets and film evaporation is carried out. A hybrid Eulerian-Lagrangian model has been adopted on a multi-region configuration, accounting for fluid-solid conjugate heat transfer (CHT), which plays a key role in the conversion strategy: it has been demonstrated that the heated structure can be exploited to significantly increase the exhaust gas enthalpy in the cold start, which represents an important improvement for pollutant conversion. Different heating strategies are analysed, with the objective of maximising the spray evaporation and the uniformity of the ammonia distribution downstream of the mixer. The objectives of this work are emphasizing the improvements that an electrically heated mixing catalyst can bring to the traditional SCR configuration, laying the foundation for other following studies.

Study of flow and heat transfer characteristics of a liquid jet impinging on a heat sink with discontinuous staggered ring ribs

The temperature uniformity of the bottom surface of the heat sink is one of the hot research topics in the field of jet impingement heat transfer enhancement. In this study, jet impingement on a heat sink with novel discontinuous staggered ring ribs in the wall jet region is put forward to improve the local heat transfer by combining a single micro-jet impact with the secondary flow channel. The flow and heat transfer characteristics of the confined liquid jet impinging on the ribbed head sink under different structural parameters of ribs and jet Reynolds numbers are numerically studied. The V2F turbulence model is used for numerical calculation and the obtained results are compared with the experimental results. The results show that discontinuous staggered ring ribs in the wall jet region of the heat sink promote the formation of secondary flow and strengthen the fluid-solid conjugate heat transfer, that effectively improve the temperature uniformity of the entire heat sink. The temperature difference of the ring-ribbed heat sink is about 91.82% lower than that of the flat plate heat sink when the Reynolds number is 8000. When the outlet shrinkage ratio decreases, or when the position radius of the first layer of ribs or arc angle of a rib on the first layer increases, the temperature uniformity of the ring-ribbed heat sink is gradually improved. However, the lifting range of the outer edge of the heat sink decreases. Also, when the jet Reynolds number increases to 20,000, the maximum temperature difference of the heat sink decreases down to 1.6 K.

Multi-objective optimization of multi-stage heat sink of electric aircraft using three-dimensional thermal network analysis

The efficiency, reliability, and safety of aircraft have been improved by substituting hydraulic and mechanical systems with electric systems. Furthermore, in future electric aircraft, where fan-driving engines are partially replaced by electric motors, solving the thermal management of heat generation from the motor-controlling power-devices will become a crucial problem. In this study, three-dimensional steady thermal network analysis (TNA) was carried out to analyze the temperature field in a heat sink, for motor-controller air cooling, which is expected to be used for the future electric aircraft. The numerical procedure used was verified by comparing the results of TNA with those of three-dimensional fluid-solid conjugate heat transfer analysis using finite volume method. After the verification, TNA was carried out for an aircraft flight scenario, where the optimum geometry of the heat sink was investigated, minimizing the following three objective functions: the pressure loss of air flow through the heat sink, the maximum local wall temperature of the heat sink at the surface of motor controller, and the weight of the heat sink. In this multi-objective optimization, the design of experiments technique was used to decide the space-filling points for the six design parameters. The three objective functions at each sampling point were calculated using TNA. A response surface was created for each objective function. A multi-objective optimization on the response surfaces, using a genetic algorithm, was iteratively carried out to find the Pareto optimal solutions for the air-cooled multi-stage heat sink. From the results of the Pareto optimal solutions, the effects of the design parameters on the objective functions were discussed. In addition, multiple regression analysis was performed for quantitative evaluation of the results of the Pareto optimal solutions, and the dominant design parameters for each objective function were identified.

Influence of conjugate heat transfer on the minimization of entropy generation for forced convective flow through parallel plate channel filled with porous material

AbstractA fluid–solid conjugate heat transfer model is developed to analyze the characteristics of entropy generation for forced convective steady hydrodynamically fully developed laminar flow of a Newtonian fluid through a parallel plate channel filled with porous material by modulating the following parameters: substrate thickness, the ratio of thermal conductivity of wall to fluid, Biot number, the axial temperature gradient in the fluid, and Peclet number. The exteriors of both the walls are subjected to the thermal boundary conditions of the third kind. The mass and Brinkman momentum conservation equations in the fluidic domain and the coupled energy conservation in both the solid and fluidic domain are solved analytically using the local thermodynamic equilibrium model, so as to derive closed‐form expressions for the velocity in the fluid and the temperature both in the fluid and solid walls in terms of relevant parameters. Suitable combinations of influencing factors, namely the geometric parameters of the system, fluid, flow, and substrate properties are identified for which global entropy generation rate is minimized. The findings may be helpful in the design of thermal systems frequently used in diverse engineering applications having heat transfer in the solid wall being a crucial parameter.

Concept design and numerical evaluation of a highly efficient rotary electrocaloric refrigeration device

Abstract Enabled by the discovery of giant electrocaloric effect (ECE) in inorganic ceramics and organic polymers, Electrocaloric (EC) cooling technology has attracted considerable attention from both academia and industrial. However, there remains many challenges in the refrigeration efficiency and/or capacity of the currently reported electrocaloric refrigeration devices. In this work, we propose a concept design of EC refrigeration device, in which the working bodies are rotating in a plane perpendicular to the direction of fluid flow. The rotary EC device adopting heat transfer fluid as an intermediate medium allows for improved heat exchange between EC materials and outside environment, and efficiently delivers cooling effects to where it’s needed. Simulations have been performed to investigate the system cooling performance under different operating strategies. Meanwhile, comparative researches on different heat transfer fluid are conducted and the corresponding cooling effects are studied. When using deionized water as heat transfer medium, the system can achieve a cooling power density of 9.89 W·cm−3 and COP of 10.48 over 10 K temperature span. In general, this work provides a highly-efficient rotary EC refrigeration device concept that employs fluid–solid conjugated heat transfer, and guides the optimization of operating strategy and selection of heat transfer fluid.

Temperature rise characteristics for angular-contact ball bearings with oil-air lubrication based on fluid-solid conjugate heat transfer

At present, the thermal analysis of oil-air-lubricated angular-contact ball bearings uses empirical heat transfer coefficients to calculate heat transfer. This approach presents problems such as simulating the actual lubrication flow field and ignoring the internal heat conduction in the bearing ring. This paper proposes a CFD steady-state analysis model of oil-air-lubricated angular-contact ball bearings based on fluid-solid conjugate heat transfer to analyze the flow field and temperature field. A temperature rise test of oil-air-lubricated angular-contact ball bearings was carried out to verify the positive determination of the simulation analysis results. Based on a fluid-solid conjugate heat transfer steady-state analysis model, the effects of lubrication parameters, operating conditions, and rolling element materials on the temperature rise characteristics of oil-air-lubricated angular-contact ball bearings were studied. The research results provide a method for analyzing the temperature rise characteristics of oil-lubricated bearings and provide a basis for the analysis of oil-lubricated bearing life.

Thermal Modeling and Experimental Validation in the Rotor Region of Hydrogenerator With Different Rotor Structures

Thermal management is often considered a bottleneck in the pursuit of the next generation hydrogenerator in the electric power system. Overheating of the complex rotor parts has become one of the main problems affecting safe and stable hydrogenerator operation. In this paper, a 250 MW hydrogenerator is analyzed. The transient electromagnetic field of the hydrogenerator is calculated and the losses of the rotor parts are obtained. The rotation of the hydrogenerator rotor is considered. Three-dimensional fluid and thermal mathematic and physical models of the hydrogenerator are established. The loss values from electromagnetic field calculations are applied to the rotor parts as heat sources in the temperature field. After solving the fluid and thermal equations of fluid-solid conjugated heat transfer, influence of the structures of rotor support plate, rotor pole body insulation, and rotor excitation winding on the fluid flow and temperature distribution in the rotor region of hydrogenerator is studied using the finite volume method. The calculated temperature result of rotor excitation winding is compared with the measured value. The calculated temperature result agrees well with the measured value. It provides an important reference for optimizing the rotor structure of the larger hydrogenerator.

Temperature characteristics of high repetition rate water-cooled Nd:YAG active mirror amplifier

In order to deal with the thermal management problem of high-energy high-repetition rate laser amplifiers, the efficient heat removal in water-cooled Nd:YAG active mirror amplifiers is investigated in detail through numerical modeling and experimental analysis. According to the low Reynolds number <i>k-ε</i> turbulence model, a full fluid-solid conjugate heat transfer model is established to give a comprehensive model of flow and thermal characteristics in three dimensions. The thermal distributions obtained from the model are then used to calculate all mechanical stresses in the laser medium and thermally-induced wavefront distortions. In comparison with the standard <i>k-ε</i> turbulence model, the influences of the near-wall treatments of the above model on the process of fluid flow, convection diffusion and heat conduction, and temperature distributions are analyzed. Meanwhile, the effects of coolant flow rate and pump parameter on the flow field characteristics, temperature and wavefront distributions of the YAG disk are also studied. Numerical simulation results reveal that the temperature distribution of the laser medium is closely related to the viscous effect in the solid-liquid boundary layer. Although the heat deposition distribution of the laser medium is symmetrical, the temperature profile is asymmetrical as a result of the increasing water temperature along the water flow. The maximum temperature rise of the disk is at the outlet end, and the position remains almost unchanged. The front-surface temperature distributions and wavefront profiles of Nd:YAG vary nonlinearly with the coolant flow rates, but linearly with the pump parameter. Model predictions show that when the laser amplifier operates at a repetition rate of 50 Hz, the thermal diffusion of the coolant mainly occurs in a range of 100 μm, and the maximum temperature difference of the coolant reaches up to 10.85 ℃. Correspondingly, the maximum temperature variation over the front-surface active region is less than 4 ℃, with an average temperature of 49.62 ℃, which leads to a total peak-to-valley wave front distortion of 7.27<i>λ</i>. The experimentally measured temperature distributions are in reasonable agreement with numerical simulations. The research results are beneficial to designing and optimizing the high-energy, high-repetition rate water-cooled Nd:YAG active mirror amplifiers.

Study on seepage and deformation characteristics of coal microstructure by 3D reconstruction of CT images at high temperatures

To study the seepage and deformation characteristics of coal at high temperatures, coal samples from six different regions were selected and subjected to computed tomography (CT) scanning studies. In conjunction with ANSYS software, 3D reconstruction of CT images was used for the establishment of fluid-solid conjugate heat transfer model and coal thermal deformation model based on the microstructures of coal. In addition, the structure of coal was studied in 2D and 3D perspectives, followed by the analysis of seepage and deformation characteristics of coal at high temperatures. The results of this study indicated that porosity positively correlated with the fractal dimension, and the connectivity and seepage performances were roughly identical from 2D and 3D perspectives. As the porosity increased, the fractal dimension of coal samples became larger and the pore-fracture structures became more complex. As a result, the permeability of coal samples decreased. In the meantime, fluid was fully heated, generating high-temperature water at outlet. However, when the porosity was low, the outlet temperature was very high. The average deformation of coal skeleton with different pore-fracture structures at high temperatures showed a trend of initial increase and subsequent decrease with the increase of porosity and fractal dimension. The maximum deformation of coal skeleton positively correlated with connectivity but negatively correlated with the fractal dimension.

A study of rewetting and conjugate heat transfer influence on dryout and post-dryout phenomena with a multi-domain coupled CFD approach

In the present study, a multi-domain coupled computational fluid dynamics (CFD) approach is developed for the modeling of dryout and post-dryout heat transfer. For the fluid part, the thin film and gas core are modeled by the liquid film model and two-fluid model, respectively. For the solid part, the heating process is modeled by either using a constant heat source or solving the Joule heating problem. The fluid-solid conjugate heat transfer is calculated by using carefully designed coupling schemes which can automatically determine the operation mode for pre- and post-dryout regions. Unlike standalone simulations where only the inner wall temperature is predicted, coupled simulations are able to predict the outer wall temperature, allowing a direct comparison with experiments. Simulations were carried out for a wide range of flow conditions and validated against the corresponding steady state experiments. By newly introducing a film rewetting model, the current CFD code is capable of simulating the transient behavior of dryout. With the rewetting model, the coupled code successfully predicted the dryout hysteresis.

Numerical evaluation of a kilowatt-level rotary electrocaloric refrigeration system

Abstract Electrocaloric (EC) cooling technology has rejuvenated rapidly in recent years and gained the great attention in both academia and industrial. Currently, there are only handful studies of EC cooling devices reported over the years, and most of them are focusing on small-scale cooling applications. For practical application, however, it is essential for an EC device to achieve a kilowatt level of cooling power. In this work, we develop a rotary EC device, in which the working bodies are rotating in-plane, and the heat transfer fluid flow through the working bodies in out-of-plane direction. The design allows the continuous fluid–solid conjugated heat transfer and exhibits kilowatt level of cooling power. Numerical study has been performed to explore the internal correlation between the key parameters of the working condition and performance of the device. For a given EC working body, the electric-induced heat generation/absorption is found to significantly affect the cooling power. Meanwhile, parametric studies on the temperature span and cyclic period of the system are conducted. By fine-tuning the operation parameters, the system achieves an optimized overall performance, i.e., a cooling power of 1729.90 W, when operated over a temperature span of 10 K and cyclic period of 10 s. This work provides a general topological design of a rotary device that employs fluid–solid conjugated heat transfer, and guides the optimization of operation parameters to achieve giant cooling power.

Three-dimensional lattice Boltzmann flux solver for simulation of fluid-solid conjugate heat transfer problems with curved boundary.

A three-dimensional (3D) lattice Boltzmann flux solver is presented in this work for simulation of fluid-solid conjugate heat transfer problems with a curved boundary. In this scheme, the macroscopic governing equations for mass, momentum, and energy conservation are discretized by the finite-volume method, and the numerical fluxes at the cell interface are reconstructed by the local solution of lattice Boltzmann equation. For solving the 3D fluid-solid conjugate heat transfer problems, the density distribution function (D3Q15 model) is utilized to compute the numerical fluxes of continuity and momentum equations, and the total enthalpy distribution function (D3Q7 model) is introduced to calculate the numerical flux of the energy equation. The connections between the macroscopic fluxes and the local solution of the lattice Boltzmann equation are provided by the Chapman-Enskog expansion analysis. As compared with the lattice Boltzmann method, in which the time step and grid spacing are correlated, the local solution of the lattice Boltzmann equation at each cell interface used in the present scheme is independent of each other. As a result, the drawback of the tie-up between the time step and grid spacing can be effectively removed and the developed method applies very well to nonuniform mesh and curved boundaries. To validate the performance of the developed method, the steady and unsteady natural convection in a finned 3D cavity and in a finned 3D annulus are simulated. Numerical results showed that the present scheme can effectively solve the 3D conjugate heat transfer problems with a curved boundary.

The cooling mechanism of minuscule ribbed surfaces

One reason human beings wear stockings is to warm their legs. Ordinary textile materials are thermally insulative, which prevents body’s heat from dissipating. In contrary to this common sense, it was discovered that some knitted stockings made up of them permanently promote heat release and cool body. This non-intuitive phenomenon emerges when micro-size yarns are knitted to form wide spacing between neighboring yarns. However, the reason why they cool body was unclear because conventional principles of cooling garments cannot account for it. Here, in the basis of fluid-solid conjugate heat transfer analysis of natural convection, we have clarified the cooling mechanism originates from relative relationship between their geometric structure, a periodic alignment of minuscule ribs, and thermal boundary layer. Our novel finding revealed that sufficiently small ribs on the surface are exposed to steep temperature gradient within thermal boundary layer. Thereby, thermal conduction via ribs is enhanced complementarily as they are separated to guide cooler flow onto the surface. Our study provides a general insight into understanding permanent cooling mechanism on micro-size ribbed surfaces in contrast to conventional theory for heat sink, which is applicable not only to other clothes, but also to artificial devices or natural structures.

Thermomechanical Analysis of Purging Plugs by Applying Fluid–Solid Conjugate Heat Transfer Modeling

Purging plugs are important functional units in advanced steel‐making processes, which experience extreme heat exchange and temperature changes during the purging procedure. Fluid–solid conjugate heat transfer modeling is conducted to determine the inconstant and instantaneous heat transfer coefficients at slit walls. Further thermomechanical simulations are performed on the purging plug by assuming elastic material behavior. Dimensionless temperature change and stress analysis indicate that transverse tensile failure is highly likely at the area close to 0.323 m from the base of the frustum purging plug. A comparison with practical observations proves that thermomechanical modeling coupled with the fluid–solid conjugate heat transfer method is a useful approach for investigating purging plugs under practical service conditions, as well as other cases involving fluid–solid interactions.