Influence Of Heat Source Research Articles

Mechanics of blood flow through narrow artery using Prandtl viscoelastic model

BackgroundThe mechanics of blood flow via converging diverging conduits is an intriguing phenomenon that involves multiple fundamental principles of fluid dynamics. Blood arteries can diverge, which means they expand, or converge, which means they contract down. This specific structure is essential for controlling blood flow and preserving adequate circulation across the body. The theory of fluid mechanics is significant concept related to blood flow along converging/divergent channels. Elevated shear strains near the narrower artery throat can stimulate platelets, causing thrombosis that can completely or partially stop blood supply to the human brain or heart. This communication addresses the blood flow in convergent and diverging artery using fundamental concept of fluid mechanics. The Prandtl fluid model is considered as a blood, because of its viscoelastic nature. The influence of heat source, frictional dissipations and a chemical reaction are included. MethodsThe Jaffrey-Hamel flow in a converging and diverging conduits is generalized to Prandtl fluid model considering the purely radial flow through cylindrical pipe like artery with an arbitrary cross section. The governing equations are solved computationally using the Runge–Kutta-Fehlberg (RKF-4) method. Significant findingThe rheological parameters ε and δ of blood show opposite tendencies for blood circulation. The Brownian and thermophoresis parameters has a significant effect on heat and mass transport rate. The presence of slip (semi blockage) produces flow reversal and higher drag forces at the arterial wall. Significant flow dynamics and heat-mass transport was reveled for diverging (wider) artery β > 0. The non-uniform heat source show similar trends for thermal profile and heat transfer rate.

Thermodynamics of hydromagnetic boundary layer flow of Prandtl nanofluid past a heated stretching cylindrical surface with interface slip

BackgroundThe mathematical modelling of a non-Newtonian fluid in the backdrop of applied magnetic field against an electrically conducting liquid is recognized as magnetohydrodynamics (MHD), which has important implications in chemical engineering and the biological sciences. Illustrations of such magneto-fluids include molten metals, electrolytes, blood plasma, and salty water. The applications of flowing liquids over cylindrical geometries is a fascinating due to its wide range importance in engineering. The aforementioned uses of MHD encourage scientists and analysts to establish new mathematical modelling in the area of fluid dynamics. Therefore, we considered the Prandtl fluid flow with loaded nanoparticles over a cylindrical tube with slip triggered by wall shear stress. The transport equation involving thermophoresis and Brownian diffusions are modelled using the Buongiorno model. The modelling of energy and entropy are established considering the effects of frictional dissipation, non-uniform heat source, thermal stratification, and Ohmic heating. MethodsThe formulated mathematical model leading to a complex system of partial differential equations with numerous integrated parameters. Using numerical algorithm RK-45 with a tolerance limit of 10−6, the system of resultant ordinary differential equations is simulated. The solver is used repeatedly to select the parameters that best meet the intended boundary conditions. Significant findingThe results of the current study revealed that the influence of heat source and thermal stratification on fluid temperature are conflicting. Additionally, the magnetic variable and Brinkman parameter have an escalating relationship with the rate of entropy development. The Bejan number detract with the magnetic variable. For distinct estimations of slip factors, heat and mass transport behave identically. However, the effect of slip is higher as compared to no slip scenario. The effect of Lewis number against nanoparticles concentration is opposite.

Influence of Heat Source on Thin Film Flow of Ferrofluid Past an Unsteady Stretching Sheet

In this work, the impact of a heat source on the thin-film ferrofluid flow over an unstable stretching sheet in the presence of an external magnetic field has been examined. The governing partial differential equations are transformed into a system of ordinary differential equations by similarity transformation. The resultant system of ordinary differential equations is solved numerically through shooting technique involving Runge-Kutta-Fehlberg (RKF45) method. To improve the initial guess values, the Newton-Raphson method is used. The significance of magnetization parameter, Prandtl number and heat source parameter on the flow and heat transmission process have been graphically analysed. The decrease in film thickness is observed for growing values of heat source parameter.

Preoperative Anxiety and Postoperative Pain in Children with Burn Patients and Their Correlation Analysis

Background: Burn is a kind of skin tissue damage under the influence of heat source, which is a common type of accidental injury in current society. Objective: To investigate the status of preoperative anxiety and postoperative pain in children with burn patients, and to analyze the correlation between preoperative anxiety and postoperative pain. Methods: A total of 108 pediatric patients who underwent burn surgery under general anesthesia in our hospital from October 2020 to August 2021 were selected. FLACC and Facial Expression Pain Scale were used to evaluate the pain of the children, and STAI and YPAS were used to evaluate the anxiety of the children. Correlation was used to analyze the effect of preoperative anxiety on postoperative pain in burn children. Results: Preoperative anxiety and severe anxiety accounted for more than 50% of burn children, and there was a statistically significant difference in preoperative anxiety and postoperative pain between 1-3-year-old children and 4-12-year-old children. The influencing factors of postoperative pain in children with burns were analyzed, including burn area, depth of burn, and previous operations. The multivariate analysis showed that the risk factors for postoperative pain in children were age, burn area, depth of burn, preoperative anxiety of children, and parental trait anxiety, after statistical test, it shows that each influencing factor has a significant influence on postoperative pain in children (P < 0.05). In the correlation analysis of preoperative anxiety and postoperative pain in children with burns, it was shown that preoperative anxiety in children aged 1 to 3 years had a significant impact on postoperative pain of children, and the correlation analysis showed that preoperative anxiety of children with burns There was a positive correlation between anxiety score and postoperative pain (r=0.479, P=0.001). Conclusion: The incidence of preoperative anxiety in children with burn patients is high, and the postoperative pain scores are also different in different age groups. In addition, there is a current correlation between preoperative anxiety and postoperative pain in children with burn patients, and the correlation is positively correlated, that is, the higher the patient's anxiety score, the more intense the patient's postoperative pain.

Non-Fourier energy transmission in power-law hybrid nanofluid flow over a moving sheet

Ethylene glycol is commonly used as a cooling agent in the engine, therefore the study associated with EG has great importance in engineering and mechanical fields. The hybrid nanofluid has been synthesized by adding copper and graphene nanoparticles into the Ethylene glycol, which obeys the power-law rheological model and exhibits shear rate-dependent viscosity. As a result of these features, the power-law model is utilized in conjunction with thermophysical characteristics and basic rules of heat transport in the fluid to simulate the physical situations under consideration. The Darcy Forchhemier hybrid nanofluid flow has been studied under the influence of heat source and magnetic field over a two-dimensionally stretchable moving permeable surface. The phenomena are characterized as a nonlinear system of PDEs. Using resemblance replacement, the modeled equations are simplified to a nondimensional set of ODEs. The Parametric Continuation Method has been used to simulate the resulting sets of nonlinear differential equations. Figures and tables depict the effects of physical constraints on energy, velocity and concentration profiles. It has been noted that the dispersion of copper and graphene nanoparticulate to the base fluid ethylene glycol significantly improves velocity and heat conduction rate over a stretching surface.

Thermally radiated jeffery fluid flow with nanoparticles over a surface of varying thickness in the influence of heat source

The current study examines the magnetohydrodynamic flow, heat and mass transfer in radiated Jeffery fluid containing nanoparticles. The fluid motion is considered due to the non-linear stretch of a sheet of non-uniform thickness. The effects of Brownian and thermophoresis in the nanofluid model are described. The governing partial differential equations are transformed into the nonlinear ordinary differential equation using a new set of similarity variables and then solved numerically using MATLAB bvp4c algorithm. The simulated results are presented for various values of physical parameters involved in the study. Novel attributes of these parameters are deliberated through graphs and tables. It is observed that the sheet thickness parameter α and Deborah numberβ have inverse impact on fluid flow and temperature. The fluid temperature rises with the increase in radiation parameter R and heat source parameter δ. Increment in Prandtl number, Lewis parameter, Brownian motion leads to suppress the nanoparticle concentration. Furthermore, the skin friction coefficient and Nusselt number are calculated for the different values of velocity power index s (0 <s<5) and sheet thickness parameter α. Also, a comparative study is carried out with published work and the outcomes are observed in good agreement.

Effect of heat source on Rayleigh–Bénard convection in rotating viscoelastic liquids

AbstractThe influence of heat sources on instability in rotating viscoelastic liquids is studied. Linear stability analysis is done using normal modes. Computations are done for 10 boundary combinations and the results reveal that convection manifests via the oscillatory mode in this case. The critical values of the oscillatory and stationary instability have been studied. The results indicate individual stabilizing influences of rotation and strain retardation along with heat source in the case of free isothermal boundary conditions. It has quite unpredictable influences on the system stability in all the other boundary conditions for the chosen parameters. By suitable limiting processes, results pertaining to Oldroyd liquid B will lead to those of Maxwell, Newtonian, and Rivlin–Ericksen liquids. The problem finds applications in a working media consisting of viscoelastic liquids with nonisothermal systems.

Entropy generation in thermal radiative oscillatory MHD couette flow in the influence of heat source

Entropy generation and their minimization for magnetohydrodynamic oscillatory couette flow through a vertical channel, soaked with a porous medium in the existence of heat source and thermal radiation has been deliberated. In the present analysis, flow governing equations are elucidated and extricated with the help of analytical technique for the fluid velocity profile, temperature field, irreversibility distribution and Bejan number. Also, the numerical value of dimensionless shearing stress and heat transfer coefficient are obtained and presented through tables with reference to flow governing parameters. It has noticed that entropy generation can be regulated or minimized with the change in the applied magnetic field and thermal radiation, and this result is useful in several thermodynamic industries and engineering field for attaining the high performance of devices with minimum heat loss.

Influence of Heat Source on Thermal Behaviour of Solid Cylinder.

The present manuscript deals with determination of influence of internal heat source on thermal behaviour of a long solid cylinder. A direct, steady state, nonhomogeneous boundary value problem with internal heat generation is formulated to analyse heat transfer and thermal stresses. The cylindrical surface heat source situated in annular region of long cylinder results in internal heat generation. Finite Hankel transform, Goodier’s thermoelastic displacement potential and Michell function are adopted to obtain the analytical solution. The outcomes are represented in the form of infinite series comprising Bessel’s functions. By considering a mathematical model for steel plate, outcomes are verified numerically. Some numerical results for the temperature distribution, displacement components, and the associated stresses are shown in figures drawn using Matlab software.

Heat generation and chemical reaction in flow propagated by peristalsis incidence of radiation in MHD Jeffrey nanofluid

Objectives: In the present study, the heat Source and chemical reaction in MHD Jeffrey nanofluid driven by means of peristalsis through asymmetric channel has been addressed. Methods: Considering low Reynolds number and long wave length assumptions the fundamental equations of mathematical model are obtained. By applying long-wavelength and low Reynolds’s number the nonlinear partial differential equations are transformed into ordinary differential equations. The simplified equations are solved by using Mathematica software and various effects are discussed in the form graphs. Findings: It is observed that influence of chemical reaction parameter on temperature and concentration profiles are increasing. The converse behavior is found in the case of Radiation and heat source parameters. Novelty: The present analysis is applicable for magnetic drug targeting for various treatments in a human body. The present study addresses the influence of heat source and chemical reaction in peristaltic pumping of Jeffrey nanofluid incidence of thermal radiation. Keywords: Peristalsis; Jeffrey fluid; thermal radiation; MHD; heat generation

Influence of heat source on viscous dissipative hydromagnetic fluid flow in a permeable vertical channel subjected to time‐periodic boundary conditions

AbstractUnsteady heat‐generating natural convective viscous dissipative fluid flow through a permeable steady‐periodic vertical channel in the presence of heat source is studied. The coupled partial differential governing equations of the problem are simplified to obtain second‐order nonlinear ordinary differential equations. The resulting differential equations are solved using differential transform method to obtain approximate solutions for the momentum and energy equations. The impacts of pertinent parameters, such as heat source/sink (), Prandtl number (), viscous heating (), suction/injection (S), and Strouhal number (), on the velocity and temperature distributions in the periodic regime are illustrated using graphs and discussed. From the computational results, it is observed that an increase in the values of heat source/sink parameter () in the presence of viscous dissipation has significant influence on the flow and heat transfer. This study provides useful information in handling and processing the extraction of crude‐oil‐based slurries.

Heat transfer in combined convective magnetohydrodynamic motion of nanofluid holding different shapes of nanoparticles in a channel under the influence of heat source

Heat transfer in mixed convection unsteady MHD flow of an incompressible nanofluid in a channel under the influence of heat source is studied. The channel with non-uniform walls temperature is taken in a perpendicular direction with a transverse magnetic field. Based on the substantial boundary conditions, three different flow conditions are examined. The problem is formed in PDEs with substantial boundary conditions. Four different forms of nanoparticles of identical volume fraction are employed in traditional base fluid water (H2O). Solutions for momentum and energy are attained by the perturbation method and examined graphically in different graphs. It is established that viscosity and thermal conductivity are the mainly well-known variables accountable for different results of velocity and temperature. It is also found that increasing heat source leads to an increase in nanofluid velocity and temperature and nano-size particles instance platelet and blade shapes have lesser momentum as related to brick and cylinder size of nanoparticles.

Influence of heat sources and shielding gases on properties of material when producing aviation details by direct growth method

The purpose of the research is to determine at what source of heating and with the use of which shielding gas the deposited material will have the highest values of physical and mechanical characteristics. It is necessary to assess the quality, size and uniformity of distribution of the deposited layers, the geometry of obtained surface. To perform the tasks set in this work, we applied the methods of research of the chemical composition, structure and properties of the experimental alloys. We used the methods of qualitative and quantitative assessment of structural components, the determination of physical, mechanical and structural properties of the material under study. The object of the study was the AlSi5 alloy grown using two parameters affecting the quality of the grown material - heat sources: electric arc and welding arc with cold metal transfer (CMT − Cold Metal Transition) in argon. The main indicators of the properties of the aluminum alloy, which were determined in the experiment, are following: tensile strength (σв), yield strength (σ0.2), elongation (δ). As a result of the research, it was revealed that the influence of heat sources on the formation of the surface of the deposited plates, the samples obtained by the method of plasma-jet facing have a protrusion of the deposited layers of the lateral surface to a height of 1.5 mm. Samples obtained by the method of electric arc welding both in argon and helium have a height of up to 0.3 mm. Analysis of the chemical composition showed that each source of heating made it possible to ensure the chemical composition of the finished product, corresponding to the chemical composition of the original material. The CMT process provided the most accurate distribution of alloying elements. The physicomechanical properties of the plates obtained by the direct growth method are approximately at the same level with the materials that were obtained by traditional casting methods. The highest values of mechanical properties have the samples obtained by the method of SMT facing: σв = 19 МPa; σ0.2, = 13 МPa; δ = 12 %, which can be explained by more dispersed structure. The scientific novelty of the research lies in the fact that the influence of each heat source on the change in the physical and mechanical properties was revealed. Effect of shielding gas during electric arc surfacing. The evaluation of the interchangeability of these processes in the manufacture of aircraft parts by the method of direct growth. The practical significance of the study allows us to determine which source of heating is more appropriate to use in order to obtain the necessary properties for a particular process.

Study on Coil Optimization on the Basis of Heating Effect and Effective Energy Evaluation during Oil Storage Process

With the rapid development of crude oil reserves, energy consumption in heating increases gradually, so it is necessary to study heating effect and energy utilization. In this paper, a theoretical model of coil heating process for large floating roof crude oil tank is established, with dynamic thermal environment and variable physical parameters of oil products taken into consideration comprehensively. The influence mechanism of coil structure on the coupling characteristics of heat transfer and flow of crude oil during heating process is revealed. On this basis, the heating effect of crude oil in storage tank is evaluated from the point of view of time and space respectively. Simultaneously, the properties of energy and its quality are both considered, the effective energy utilization efficiency of crude oil in storage tank during heating process is analyzed, and an optimization method for heating coil of tank oil is proposed. The results show that the temperature of oil products in the center and bottom of the tank increases linearly with the influence of heat sources, and the temperature of oil products at the roof and wall of the tank is greatly affected by the dynamic thermal environment, which is showing a change regulation of fluctuating pattern. The heating effect is greatly affected by coil length. The increase of coil length can obviously improve the flow structure of crude oil in the tank. A larger eddy structure can be formed in a shorter period of time, which can increase the heating rate of crude oil and further reduce the non-uniformity of temperature field. However, effective energy efficiency is greatly affected by coil diameter. The increase of coil diameter increases the convective heat transfer coefficient between coil and crude oil, which promotes crude oil to absorb heat more easily from heat sources and improves the effective utilization of energy and exergy. Therefore, the heating effect and effective energy utilization of oil coil can be further optimized by changing the length and diameter of coil. Relevant research results can provide theoretical and technical support for improving the utilization efficiency of reserve energy and reducing the cost of reserve energy consumption.

Transient Temperature Field Model of Wear Land on the Flank of End Mills: A Focus on Time-Varying Heat Intensity and Time-Varying Heat Distribution Ratio

Modelling methods for the transient temperature field of wear land on the flank of end mills have been proposed to address the challenges of inaccurate prediction in the temperature field of end mills during the high-speed peripheral milling of Ti6Al4V that is a titanium alloy. A transient temperature rise model of wear land on the flank of end mills was constructed under the influence of heat sources in the primary shearing zone (PSZ), rake-chip zone (RCZ), flank-workpiece zone (FWZ), and dissipating heat source. Then the transient temperature field model of wear land on the flank of end mills was constructed. Finally, the transient temperature field model of wear land on the flank of end mills was constructed. Comparison of simulation result and experimental data verified the accuracy of the model. In sum, the proposed model may provide a temperature model support for future studies of flank wear rate in end mill modeling.

Detecting the influence of heat sources on material properties when producing aviation parts by a direct energy deposition method

Quality of the material obtained by the method of direct energy deposition using three heat sources (plasma arc, electric welding arc and welding arc with cold metal transfer) was studied. AlMg5 alloy wire was used as the filler material. The study was conducted to establish at what heat source the deposited material will have the highest physical and mechanical characteristics and performance. It was also necessary to assess quality, size and uniformity of distribution of the deposited layers since these indicators determine accuracy of the resulting product and make it possible to reduce machining allowance. Influence of heat sources on formation of surface of deposited plates was revealed: the specimens obtained by the method of plasma surfacing had protrusion height of the deposited layers on the side surface up to 2 mm, the specimens obtained by the method of electric arc and CMT surfacing had protrusion height of 0.5 mm. The obtained data will enable determination of the minimum allowable machining allowance. Analysis of chemical composition has shown that each heat source ensured chemical composition of the finished product corresponding to chemical composition of original material. Distribution of alloying elements was uniform among the deposited layers. However, the CMT process provided the most accurate distribution of alloying elements. Physical and mechanical properties of the plates obtained by the direct growth method were approximately at the same level with the materials obtained using conventional methods of casting and pressing. The specimens obtained by the method of plasma surfacing had the highest values of mechanical properties: σ t =28 MPa; σ 0.2 =15 MPa; δ=30.4 % which can be explained by a more dispersed structure and a high level of fusion of the deposited layers. The obtained data will make it possible to determine which heat source is more expedient to use in order to obtain properties necessary for a concrete technological process. They also make it possible to evaluate applicability of the method of direct growth using arc heat sources in mass production of parts

Influence of heat source in a pipe on an upstream-acoustic-boundary condition

Influence of heat source in a pipe on an upstream-acoustic-boundary condition

Impact of forced convective radiative heat and mass transfer mechanisms on 3D Carreau nanofluid: A numerical study

Nanoliquids retain remarkable features that have fascinated various researchers owing to their utilization in nanoscience and nanotechnology. We will present a mathematical relation for 3D forced convective heat and mass transfer mechanism of a Carreau nanoliquid over a bidirectional stretched surface. Additionally, the features of heat source/sink and nonlinear thermal radiation are considered for the 3D Carreau nanoliquid. The governing nonlinear PDEs are established and altered into a set of nonlinear ODEs by utilizing a suitable conversion. A numerical approach, namely the bvp4c is adopted to resolve the resultant equations. The achieved outcomes are schemed and conferred in detail for somatic parameters. It is realized that amassed values of Brownian motion parameter $N_{b}$ lead to enhance the temperature of the Carreau nanoliquid while quite conflicting behavior is being noticed for the concentration of the Carreau nanoliquid. Moreover, it is also noted that the influence of heat source $\delta > 0$ is relatively antithetic to heat sink $\delta < 0$ parameter, whereas an analogous impact is being identified for thermal Biot number $\gamma$ on temperature and concentration Biot number $\gamma_{1}$ on concentration of the Carreau nanoliquid for shear thinning/thickening liquids. Additionally, an assessment between the analytical technique, namely the homotopy analysis method (HAM) and the numerical scheme bvp4c is presented graphically, as well as in tabular form. From these comparisons we initiate a splendid communication with these results.

Study of Micro-hardness of High-Speed W9Mo4Co8 Steel Plates in Pendulum Grinding by Abrasive Wheel Periphery

In cutting tool assembly, grinding is the most important technological step of the finishing treatment, largely determining the workmanship. An increase of micro-hardness after grinding relative to the original one indicates the dominant role of abrasive tool force impact on the ground surface. A decrease, in contrast, evidences a significant softening under the influence of heat source. This research based on nonparametric statistics to predict the effect of wheel characteristics with abrasives 25A, 92A/25A, 34A, 5A, EKE, 5NQ, TGX, 5SG and with graininess 46 (F46), 60 (F60), 80 with different porosities (structure numbers 6-12), and the expected measures of position and dispersion on the micro-hardness of the surface of a high-speed cutting plate (HSCP) made of W9Mo4Co8 steel. It was found that grinding this HSCP by wheels 5NQ46I6VS3, 5SG46K12VXP, 5SG60K12VXP, 5SG46I12VXP, 25AF46M12V5"“PO, 25AF46M12V5"“PO3, 25АF46M10V5"“PO, 25AF46M10V5"“PO3, 25AF46K10V5"“PO3, 25AF60M10V5"“PO3, 25AF46L10V5"“KF35, EKE46K3V, 92A/25AF46L6V20 occurred without surface softening for 50% of the details from the operating batch.

Influence of Heat Sources and Thermal Boundary Conditions on Natural Convective Currents in a Trapezoidal Porous Cavity

This paper deals with steady laminar natural convective Darcian flow of a viscous incompressible fluid in a finite trapezoidal cavity filled with isotropic permeable material of low permeability. The vertical side walls of the cavity are assumed to be adiabatic, whereas the lower horizontal and the sloping upper walls are isothermal but with different temperatures. It is further assumed that the flow domain is subject to heat sources/sinks of uniform strength, resulting in the internal generation or absorption of heat. The governing non-dimensional partial differential equations, together with an appropriate set of thermal conditions and subject to Boussinesq approximation, have been solved numerically. The effects of a number of important non-dimensional quantities, namely Rayleigh–Darcy number, aspect ratio, internal heating parameter and inclination parameter have been discussed in relation to the isotherms and streamlines.