An experimental study for the convection HEAT transfer coefficient in a region of nanofluid containing Al2O3 oxide nanoparticles of 20 nanometer diameter in water as a base fluid through circular annular tube in the COSINE thermal FLUX boundary condition was carried out. The primary purpose of this investigation was accomplished on the surface temperature of the HEAT source (inner pipe) determined at the maximum upper than the middle of pipe for the whole entry temperatures and surface temperature for nanofluid which was less than that of the base fluid. However, the nanofluid did not have any effect on the location point on the maximum temperature surface. Then, the convection HEAT transfer coefficient and Nusselt number were scrutinized showing that both of them increase by increasing of the volume fraction and Reynolds number. The maximum value of the HEAT transfer coefficient of nanofluid belongs to the volume fraction of 1.5% and the Reynolds number near 2100 which is 19%, compared to that of the base-fluid. The effect of entrance temperature and pressure of nanofluid on the HEAT transfer coefficient was also studied. The experimental data have shown that by increasing the entrance temperature, the HEAT transfer coefficient improves but the pressure has a negligible effect on HEAT transfer. The results demonstrated that the relative pressure drop of nanofluid increased remarkably by increasing the volume fraction. Furtheremore, we observed that by decreasing the Reynolds number the pressure drop increased because of more sediment of nanoparticle at lower velocities.

One method to improve HEAT convection is to increase the HEAT transfer coefficient of the working fluid. Adding metal or non-metal nanoparticles into the base fluid, known as nanofluid, is a technique to enhance the HEAT transfer coefficient. Research in the field of nanofluids has grown significantly in the last two decades. In this study, the effects of a homogenous combination of Al2O3 and TiO2 nanoparticles with deionized water are investigated. The thermohydraulic performance of the nanofluid inside the vertical channel is analyzed by experimental and numerical methods for turbulent and laminar flow. The turbulence model utilized in computational fluid dynamics is the k-ε model. The HEATing rod in the test section produces 1 kW COSINE HEAT FLUX. The results show that increasing the concentration of nanoparticles significantly reduces the maximum temperature of the rod. The use of 1% homogeneous nanofluid reduces the maximum temperature by 20% at the Reynolds of 950 and 9.5% at the Reynolds of 4200 compared to pure water. Also, the HEAT transfer coefficient increases with the addition of nanoparticles. The difference between the results obtained by the k-ε turbulence model and the experimental method shows a difference of 10% to 13%. This research shows that the combined nanofluid with suitable thermal performance can be one of the working fluids in future thermal cycles.

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.

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.

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

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.