Second law analysis of turbulent convection flow of boehmite alumina nanofluid inside a double-pipe heat exchanger considering various shapes for nanoparticle

Journal of Thermal Analysis and Calorimetry - The main objective of this research is to study the effects of nanoparticle shape on the entropy generation characteristics of boehmite alumina...     

Multi-mode resource-constrained project scheduling problem with material ordering under bonus–penalty policies

This study emphasizes that project scheduling and material ordering (time and quantity of an order) must be considered simultaneously to minimize the total cost, as setting the material ordering decisions after the project scheduling phase leads to non-optimal solutions. Hence, this paper mathematically formulates the model for the multi-mode resource-constrained project scheduling with material ordering (MRCPSMO) problem. In order to be more realistic, bonus and penalty policies are included for the project. The objective function of the model consists of four elements: the material holding cost, the material ordering cost, the bonus paid by the client and the cost of delay in the project completion. Since MRCPSMO is NP-hard, the paper proposes three hybrid meta-heuristic algorithms called PSO-GA, GA-GA and SA-GA to obtain near-optimal solutions. In addition, the design of experiments and Taguchi method is used to tune the algorithms’ parameters. The proposed algorithms consist of two components: an outside search, in which the algorithm searches for the best schedule and mode assignment, and the inside search, which determines the time and quantity of orders of the nonrenewable resources. First, a comparison is made for each individual component with the exact or best solutions available in the literature. Then, a set of standard PROGEN test problems is solved by the proposed hybrid algorithms under fixed CPU time. The results reveal that the PSO-GA algorithm outperforms both GA-GA and SA-GA algorithms and provides good solutions in a reasonable time.     

Effect of magnetic field on laminar forced convective heat transfer of MWCNT–Fe3O4/water hybrid nanofluid in a heated tube

Journal of Thermal Analysis and Calorimetry - A numerical investigation is carried out to assess the hydrothermal performance of a water-based hybrid nanofluid containing both Fe3O4 (magnetite)...     

Incorporating novel heat recovery units into an AHU for energy demand reduction-exergy analysis

Journal of Thermal Analysis and Calorimetry - The building sector is the major energy consumer, accounting for over 40% of global energy demand. Heating and cooling together with domestic hot water...     

Forecasting the thermal conductivity of a nanofluid using artificial neural networks

Journal of Thermal Analysis and Calorimetry - In this study, the influence of incorporating MWCNT on the thermal conductivity of paraffin was evaluated numerically. Input variables including mass...     

Understanding the kinetics and mechanism of thermal cheletropic elimination of N<Subscript>2</Subscript> from (2,5-dihydro-1<Emphasis Type="Italic">H</Emphasis>-pyrrol-1-ium-1-ylidene) amide using RRKM and ELF theories

The cheletropic elimination process of N₂ from (2,5-dihydro-1H-pyrrol-1-ium-1-ylidene) amide (C₄H₆N₂) has been studied computationally using density functional theory, along with the M06-2X/aug-cc-pVTZ level of theory. The calculated energy profile has been supplemented with calculations of kinetic rate constants using transition state theory (TST) and statistical Rice–Ramsperger–Kassel–Marcus (RRKM) theory. This elimination process takes place spontaneously with an activation energy around 33 kJ/mol. Pressure dependence of the rate constants revealed that the TST approximation breaks down and fall-off expression is necessary for the kinetic modeling. At temperatures ranging from 240 to 360 K and atmospheric pressure, the unimolecular rate constant is evaluated from RRKM theory as \(k_{{(240 - 360\,{\text{K}})}}^{{1.0{\text{atm}}}} = 1.0249 \times 10^{12} \times {\text{e}}^{{ - \frac{{33.11\;{\text{kJ}}/{\text{mol}}}}{RT}}} \,{\text{s}}^{ - 1}\). Bonding changes along the reaction coordinate have been studied using bonding evolution theory. Electron localization function topological analysis reveals that the cheletropic elimination is characterized topologically by four successive structural stability domains (SSDs). Breaking of C–N bonds (Rx = 0.1992 amu^1/2 Bohr) and the other selected points separating the SSDs along the reaction coordinate occur in the vicinity of the transition state.     

Thermal conductivity of ethylene glycol-based nanofluid containing SiO2 nanoadditives: experimental data and modeling through curve fitting

Journal of Thermal Analysis and Calorimetry - The work focuses on an experimental evaluation of the changes of thermal conductivity (TC) of ethylene glycol-based nanofluid containing SiO2...     

Numerical study of melting and solidification in a wavy double-pipe latent heat thermal energy storage system

Journal of Thermal Analysis and Calorimetry - The objective of this paper is to develop the influences of channel waviness on the performance of a latent heat storage system during phase change...     

A study on the effect of magnetic field and the sinusoidal boundary condition on free convective heat transfer of non-Newtonian power-law fluid in a square enclosure with two constant-temperature obstacles using lattice Boltzmann method

Journal of Thermal Analysis and Calorimetry - In this paper, the flow pattern and thermal characteristics of free convection of a Newtonian magnetohydrodynamic fluid flow inside a square enclosure...     

Reducing AHU energy consumption by a new layout of using heat recovery units

Journal of Thermal Analysis and Calorimetry - In this study, a new design for energy recovery from the return air has been introduced to improve the air handling unit (AHU) performance through the...