In this study, by using the finite volume method, the heat transfer in a convective straight fin with temperature-dependent thermal properties and an internal heat generation under multi-boiling heat transfer modes are analyzed. In this regard, the local heat transfer coefficient is considered to vary within a power-law function of temperature. In the present study, the coexistence of all the b...

In the present study, the effective parameters of water-Al2O3 nanofluid flowing in flat tubes are investigated using the EFAST Sensitivity Analysis (SA) method. The SA is performed using GMDH type artificial neural networks (ANN) which are based on validated numerical data of two phase modeling of nanofluid flow in flat tubes. There are five design variables namely: tube flattening (H), flow ra...

Experimental data was generated by performing the experiment on a plate heat exchanger for water/water system, at different flow rate and different hot water inlet temperature, at steady state conditions. Overall heat transfer coefficient (U) is determined for the performance evaluation of plate heat exchanger. The thermal properties of water (thermal Conductivity, Specific heat and density) at...

Helical coil heat exchangers are widely used in industrial applications ranging fromcryogenic processes, air-conditioning, and nuclear reactors to waste heat recovery due totheir compact size and high heat transfer coefficient. In this kind of heat exchangers, flowand heat transfer are complicated. This paper reports a numerical investigation of theinfluence of different parameters such as coil...

The most important reason for the design of curved tubes is increasing the heat transfer between the fluid and the wall which has provided many applications in various industries such as air conditioning, micro-electric, heat exchangers and etc. The aim of this study is numerical investigation of nano fluids flow in spiral tubes with injection of base fluid in different Reynolds numbers. Accord...

Heat transfer phenomena in batch fluidized bed dryer have been studied and analyzed using three phase model including solid phase, interstitial gas phase and bubble phase based on Rizzi model. New correlations of heat transfer coefficient to surrounding and convection heat transfer coefficient between solid and interstitial gas are being proposed. In addition, some modifications have been d...

the excellent performance of fluidized bed heat exchangers is due to the interaction between particles and heat transfer surface and to the mixing effects in the viscous sublayer. in this paper, the results of experimental investigations on heat transfer for a wide range of newtonian and non-newtonian (shear-thinning power law) fluids are presented. new design equations have been developed for ...

Laminar free convection heat transfer from vertical and inclined arrays of horizontal isothermal cylinders in air was investigated experimentally and numerically. Experiments were carried out using Mach-Zehnder interferometer and the FLUENT code was used for numerical study. Investigation was performed for vertical and horizontal cylinder spacing from 2 to 5 and 0 to 2 cylinder diameters respec...

The disposal of Waste Activated Sludge is a major problem. The paper presents several disposal routes. The ultimate steps in these routes are indirect drying and subsequent incineration. Although the design of the indirect dryers is straightforward from a required heat input, operating temperature difference between sludge bed and heating medium and the heat transfer coefficient, this coefficie...