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As to different angles of attack and nonlinear problems caused by high temperatures in coexisting hypersonic aircraft, people mainly rely on fluid software for research but lack analysis of flow mechanisms. Owing to computational difficulties, few people use numerical algorithms to combine them for discussion. Hence, this study aims to make a deep inquiry into the laminar flow and heat transfer of compressible Newtonian fluid in hypersonic aircraft with small attack angles.

In this paper, on the basis of mass, momentum and energy conservation laws, the governing equations of the hypersonic boundary layer are established. Viscosity, specific heat capacity and thermal conductivity are considered nonlinear functions concerning temperature. In virtue of the MacCormack finite difference method, the stationary numerical solutions are solved directly, and the validity of the algorithm is verified.

The results demonstrate that at Mach number 5, compared to the 0° attack angle, the maximum temperature near-wall at the 3° attack angle increases by about 25%. An enjoyable phenomenon is discovered, where the position corresponding to the maximum wall shear force shifts back as the attack angle and Mach number increase. The relationship between the near-wall maximum temperature versus attack angle and Mach number is fitted through numerical calculation results.

Empirical formulas can be used to estimate heat transfer characteristics at small attack angles, which will guide the design of aircraft thermal protection systems.

To study quantitatively the effects of combined temperature dependent thermodynamics and transport fluid properties on the heat transfer rate, heat function fields and profiles in a fluid filled square enclosure.

Navier‐Stokes equations in two‐dimensions, which are the flow governing equations, were transformed into stream function and vorticity transport equations. These equations together with the energy and heat function equations were cast into their non‐dimensional forms. Numerical solutions of the resulting equations were done by the use of finite‐difference method.

The numerical investigations conducted covered the Rayleigh and Prandtl numbers in the range 10³≤Ra≤10⁶ and 0.01≤Pr≤450, respectively, and expansion parameter ε=(T_h−T_c)/T_R in the range 0.05≤ε≤1. Results show that Boussinesq‐approximation is not sufficient to simulate natural convective flow when the difference between T_h and T_c is high and close to the reference state temperature. The effects of the other fluids properties other than density can be disregarded in computation without significant loss of accuracy. Combined fluid properties have very strong effects on the heat transfer, heat function fields and profiles.

The results of this study will serve as baseline information to designers of heat transfer or process equipment in which fluid at very high temperature occurs.

The objective of this study is to highlight the questions arising in the design of district heating and cooling systems (DHCSs) in a distributed generation context and to present a model to help find cost‐effective solutions.

Literature on energy systems optimisation is reviewed and a mixed integer programming model for decentralized DHCSs design is developed and applied to two real case studies.

Distributed cooling generation partly coupled with distributed cogeneration and DH is the preferred solution in the examined areas. The optimal configurations, with special reference to network sizing and layout, significantly depend on heating demand profiles and energy prices.

Interdependencies between energy units sizing and network layout definition should be considered. Obtaining more robust and reliable network configurations should be the objective of future modelling efforts.

Despite the growth of distributed energy conversion, designers often rely on centralized concepts in order to reap economies of scale. The presented model helps in discovering less usual solutions representing the most profitable option.

Combining and comparing central and distributed production of heat and cooling under consideration of network costs.

Preface The functions of business divide into several areas and the general focus of this book is on one of the most important although least understood of these—DISTRIBUTION. The particular focus is on reviewing current practice in distribution costing and on attempting to push the frontiers back a little by suggesting some new approaches to overcome previously defined shortcomings.

The two main contributing factors that control the overall buildings’ energy performance are the heating ventilation and air conditioning (HVAC) system and the envelope design. Environmental design guidelines that consider these two factors aim to lower energy consumption. However, they are regional and climate-sensitive. This study aims to investigate how three main buildings’ envelope design variables (orientation, compactness and window to wall ratio) impact the overall building’s energy consumption within Kuwait’s regional and climate conditions.

This study simulate the energy consumption of typically shaped buildings by varying their geometry between a square to a rectangular floor plan. This study analyse the associated energy usage and provide early-stage envelope design guidance specific to the country’s conditions, to make informed decisions towards environmentally conscious buildings.

The analysed envelope variables have the potential to reduce energy consumption by 40%, and the possibility to reduce HVAC system capacity by 30%. In contrast to the general guidance in literature and standards, the simulation results demonstrate that less compact building forms perform on occasions better than the most compact ones.

The objective of this paper is to quantify the energy consumption rates for buildings located within the Arabian Peninsula, an under-studied region with potentially high interest considering three main envelope design variables. The buildings’ yearly energy consumption patterns are unique and suggest different envelope design considerations, compared to other regions with different climate conditions. This emphasises the importance of regional guidelines for the different factors associated with energy and buildings’ environmental performance.

The purpose of this paper is to evaluate differences between the results of constant property and variable property approaches in solving the problem of Al2O3-water nanofluid heat transfer in an annular microchannel. Also, the effect of nanoparticle diameter on flow and heat transfer characteristics is investigated.

Thermo-physical properties of the nanofluid including density, specific heat, viscosity and thermal conductivity are assumed to be temperature dependent. Governing equations are descritized using the finite volume method and solved by SIMPLE algorithm.

The results reveal that the constant property assumption is unable to predict the correct trend of variations along the microchannel for some of the characteristics, especially when the range of temperature change near the wall is considerable. In the fully developed region, constant property solution overestimates the values of shear stress near the walls of the microchannel. In addition, the values of Nusselt numbers are different for the two solutions. Furthermore, a decrease in wall’s shear stress has been observed as a result of increasing nanoparticle size.

This paper reflects that how the friction factor and heat transfer vary along the microchannel in temperature dependent modeling, which is not reflected in the results of constant property approach. To the best of the authors’ knowledge, there is no similar investigation of the effect of nanofluid variable properties with Pr=5 or in annular geometry.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

The purpose of the research was to develop a method for the determination of temperature characteristics of thermal diffusivity and specific heat on a single and the same stand, powered from an inverter for induction heating. Determination of the thermal diffusivity has been based on the idea of the pulse method. Searched solutions allowed to reduce inaccuracy of the pulse method when such an unusual source of pulse of energy is used.

Coupled electromagnetic and thermal calculations were carried out to verify proposed methods for estimating thermal properties of an induction heated charge. Presented methods were applied into a real laboratory stand and they were examined experimentally.

Achieved results of calculations allow to estimate thermal properties of the induction heated charge with 2 and 5 per cent of uncertainty, respectively, for heat capacity and thermal diffusivity. It gives possibility to use results as an input for further proceedings connected with estimation of electrical parameters in a more complex system.

Presented methods of estimating thermal properties of the induction heated charge were verified experimentally on a dedicated laboratory stand. It gives a practical possibility to implement previously established assumptions and examine them. This is a significant step toward the construction of an easy-to-use device for a comprehensive determination of material parameters of metals directly in the heat treatment plant.

This study presents a trial of implementation of induction heating as a source of energy in the impulse method for estimation of thermal properties of the material. Additionally, it presents a process of improving results achieved with the flash methods which were presented in previous papers. The method of estimation of specific heat which uses induction heating as the heat source was presented too.

The effective heat capacity is a key index to estimate the thermal protection performance of charring ablative materials in reentry vehicles subjected to aerodynamic heat loads. The purpose of this paper is to investigate the effects of gradient density on the effective heat capacity.

Based on the Fourier law and the pyrolysis interface model, the authors establish the governing equations for the transient heat conduction with variable density, and then simulate one-dimensional transient thermal behavior of a homogeneous and three types of non-homogeneous charring ablative material in reentry capsules by using the implicit numerical method.

The moving rate of pyrolysis interface and the surface temperature of charring ablative material depend on not only the surface heating history, but also the gradient density. And the gradient density can improve the insulation performance of charring materials, e.g. the effective heat capacity in the bilinear design is larger than that in the homogeneous design under a given heat flux condition.

This study will help the design of the thermal protection system in reentry vehicles.

While calculating internal forces of a structure resulting from temperature it is necessary to know thermal conduction and what goes hand in hand to determine temperature distribution at various points of the analysed structures. Finite strip method (FSM) is very suitable for the analysis of thermal conduction, heating, heat and temperature distribution in engineering structures, especially rectangular of identical edge conditions. The paper presents several examples of FSM application for the analysis of conduction and heat and temperature distribution for various types of engineering structures which can appear, among others, while welding several joined elements with welds made at specified speed as linear and point welds. Bars, shields, square and rectangular plates, steel orthotropic plates, steel and combined girders (steel‐concrete), box girders subject to various loads connected with heat and temperature (loaded with temperature, non‐uniformly heated surface). The obtained results may be useful in engineering practice for determining actual temperature and load capacity in individual elements of the construction.