In this paper, an inverse heat conduction problem in one-dimensional infinite domain will be considered. By employing inverse heat fundamental solution, and an over specified condition, the temperature and its heat flux will be identified.

A helical double-pipe heat exchanger filled with a porous material under asymmetric heat flux is studied analytically. Momentum and energy equations are transformed to the Germano? s coordinate and then expressions representing the velocity and temperature fields are obtained based on the powers of dimensionless curvature using perturbation analysis. To be more insightful، contours of velocity and temperature fields are presented. Results reveal an asymmetric axial velocity profile arising from the curved geometry. The Nusselt number increases with respect to the dimensionless curvature increment as well as the inner to outer radius ratio increase.

Spatial analysis of Iran's climate change from the point of view of sensible heat flux and latent heat flux by Bowen method Halimeh Shahzaei,Ms. c student of Climatology, Departement of Physical Geography, University of Sistan and Baluchistan, Zahedan, Iran. Mohsen Hamidianpour[1],Associate Professor, Departement of Physical Geography, University of Sistan and Baluchistan, Zahedan, Iran.  Mahsa Farzaneh,Ph. D Graduated. Climatology. Abstract Sensible heat flux and latent heat flux are among the variables that are closely related to temperature and humidity and show heat transfer on a surface. So, their changes can be considered related to changes in temperature and humidity. In this regard, the current research aims to analyze and reveal the climatic changes of Iran by examining the course of changes in sensible heat flux and latent heat and the ratio between the two. For this purpose, NCEP/NCAR reanalysis data including sensible and latent heat flux during the period 1948-2020 was used in Iran. Bowen coefficient was calculated from the ratio of these two heat fluxes. Interpolation methods were used for their spatio-temporal analysis. In addition, by using the non-parametric methods of Mann-Kendall and Shibsen, spatial and temporal changes were also investigated.   The first part of the results showed that, spatially, the Bowen coefficient is a function of latitude and roughness. And in terms of time, the lowest value corresponds to the month of January and the highest value corresponds to the month of July. The results of the second part show that the Bowen coefficient has a positive trend over time. Its upward trend indicates an increase in the dryness coefficient of the country. So that this situation can be seen in the positive trend and increase in temperature. Keywords: climate change, Bowen coefficient, global warming, spatio-temporal analysis.   [1]. Autehr corespound: Email: mhamidianpour@gep. usb. ac. ir

The study of the thermodynamics of relativistic fluid is important in astrophysics and modern physics. In this paper, we calculate two important parameters of the special relativistic fluids which are the viscous stress and heat flux tensors in the Cartesian coordinate system. We calculated the explicit relations of viscous stress tensor with velocity, spatial and time derivative of velocity. Also, the relation of heat flux tensor is derived with velocity, temperature and spatial and time derivatives of them. The components of viscous stress and heat flux tensors in the other coordinates can be derived by the transformation matrix. We use the relativistic method for deriving the non-relativistic viscous stress and heat flux tensors in the limit of the relativistic method. So, to improve the accuracy of non-relativistic studies of shear rate, viscous stress tensor, heat flux vector, and heat flux tensor, especially in the fast fluids, the special relativistic corrections can be used.

An analytical solution was used for obtaining the maximum allowable heat flux in symmetric composite laminates containing a quasi-square cutout with different stacking sequences subjected to uniform heat flux. The Tsai-Hill criterion was used to assess the maximum allowable heat flux of the laminate. The analytical solution was obtained based on the thermoelasticity theory and the Lekhnitskii’ s method. Furthermore, by employing a suitable mapping function, the solution of symmetric laminates with a circular cutout was extended to the quasi-square cutout. The quasisquare cutout was studied in a symmetric laminate made of Glass/epoxy with different stacking sequences of [0/90]S, [45/-45]S, [30/-30]S. The results showed that the maximum allowable heat flux experienced in perforated plates can be improved by considering the appropriate stacking sequence and the optimal values of the cutout parameters. According to the results, the best cutout geometry was not always a circle, as in some cases by choosing the appropriate values of bluntness parameter, cutout orientation, heat flux angle, cutout aspect ratio and laminate stacking sequence, a non-circular cutout provided higher maximum allowable heat flux value for a perforated plate than a circular cutout.

The cooling rate under impingement of air jet finds massive application in electronic packaging, material processing industries and cooling of gas turbine. The conventional cooling of heat sinks was till date carried out using a fan and pump. Recently, the momentous impingement of air has been found to produced 1.5 times the cooling rate, as compared with conventional method, under same pumping power. Previously, attractive amount of Research is carried out in observing the cooling rate for constant heat flux boundary condition, and less are available for constant wall temperature. The present research provides an in-depth numerical investigation for such jet impinged heat sinks, with a heat flux boundary condition. The exponential variation of heat flux magnitude with radial distance (Away from impingement point), is observed to be a generic alternate of constant wall temperature boundary condition. The numerical computation for heat transfer of such exponentially powered heat flux sink is carried out using FLUENT (ANSYS 2023R1). An orthogonal 2-D mesh computational domain with a compactible SST and K-Omega turbulence model is simulated for various inlet velocity and nozzle-target spacing. The impingement of jet and local cooling of target surface is defined using a well know non-dimensional Reynolds and Nusselt number, respectively. The exponential power for non-uniformly heated sinks can be readily selected (0.1-1) to replicate the present non-uniform heating or constant wall temperature boundary condition. Non-uniform heating has gained lots of attention of heat transfer researcher across the globe. The computation results extracted for various impinging Reynolds number and nozzle-target spacing, were closely best fitted using regression and validated with referred previous literature results. Tight dependency of slope parameter, over Reynolds number and z/d is observed in local cooling rate.  These dependencies are judged based on the power of exponents. The semi – empirical correlations are defined separately for and stagnation, transition, and wall jet regions, separately. Such correlation can plan the design of cooling system, under non-uniform heating conditions