Search results for "Heat Exchanger"

Innovative Compact Solar Air Conditioner based on Fixed and Cooled Adsorption Beds and Wet Heat Exchangers

2014

Abstract In this work, a new all-in-one compact solar air conditioner concept is presented. The system is mainly based on a new DEC process which utilises fixed and cooled adsorption beds operating in a batch process and two wet heat exchangers. The proposed innovative adsorption bed is a fin and tube heat exchanger commonly used in the air conditioning sector, wherein the spaces between the fins are filled with silica gel grains. The main feature of this component is to allow simultaneous dehumidification and cooling of air. Furthermore, since the component hosts a considerable amount of adsorption material, solar energy can be efficiently stored in the desiccant media in terms of accumula…

Correlations for estimating the specific capital cost of multi-effect distillation plants considering the main design trends and operating conditions

2018

Abstract This work proposes a correlation for the specific capital cost of multi-effect distillation (MED) plants, considering their main design options and parameters, such as the number of effects, size/capacity, and heat source temperature. These parameters are varied within a large range to cover as many different cases as possible. The cost correlation decouples the evaporator cost and includes in the expression the ratio of the heat exchanger area to a reference one. This area is calculated using a validated MED numerical model, with the results then processed to produce fitted expressions. Two versions of this correlation with different levels of complexity are proposed, which provid…

Two relaxation times and thermal nonlinear waves along wires with lateral heat exchange

2021

Abstract We propose a model for studying several nonlinear waves for heat transport along a cylindrical system with lateral non-linear heat transfer to the environment. We consider relaxational equations, each with its own relaxation time, for longitudinal heat transfer and for lateral heat transfer across the wall. We consider two kinds of nonlinear lateral heat transport: radiative heat transport, and flux-limited heat transport. This work generalizes our previous studies in which the relaxation time for the lateral heat transfer was considered equal to that of the longitudinal heat flux. We explore the influence of both relaxation times on the propagation speed of linear and nonlinear wa…

Effect of material and geometric parameters on natural convection heat transfer over an eccentric annular-finned tube

2019

In this work, the performance of an eccentric annular finned tube heat exchanger under natural convection conditions has been investigated numerically. The objective of the study is to analyse the ...

All optical solition-based 2R regeneration at 170 Gbps

2010

[NMB4]; International audience; We report the numerical and experimental studies of a spectrally filtered-based all-optical 2R regenerator at 170 Gbps. The fiber device is combined with a fast saturable absorber. BER assessment exhibits a receiver sensitivity improvement.

Flow and Heat Transfer in Corrugated Passages: Direct and Large-Eddy Simulation and Comparison with Experimental Results

1993

Novel Instrument for Temperature Measurements in Borehole Heat Exchangers

2019

The thermal response test (TRT) is the standard method for characterizing the thermal properties of the ground and those of a borehole heat exchanger (BHE). During the TRT, the inlet and outlet temperatures of the BHE are monitored. However, this test typically considers the ground as a homogeneous, isotropic, and infinite media, and therefore, it only determines the bulk and effective parameters, such as effective thermal conductivity and thermal borehole resistance. Hence, the enhanced TRT protocols are necessary where the depth-dependent temperatures are measured to estimate depth-specific thermal properties. Thus, a novel instrument with a data logger to automatically obtain the tempera…

Thermal energy storage in granular deposits

2017

Energy storage technology is crucial for the development of the use of renewable energy sources. This is a substantial constraint, however it can, to some extent, be solved by storing energy in its various forms: electrical, mechanical, chemical and thermal. This article presents the results of research in thermal properties of granular deposits. Correlation between temperature changes in the stores over a period of time and their physical properties has been studied. The results of the research have practical application in designing thermal stores based on bulk materials and ground deposits. Furthermore, the research results are significant for regeneration of the lower ground sources for…

"Thermal penalty factors" accounting for site topological characteristics in pinch design of Heat Exchanger Networks

2010

Pinch analysis allows to determine targets and solutions for minimum energy requirements in process plants, basing on innovative tools like composite curves and table problem formulation, which ultimately allow generating an optimized heat exchanger network design. On another hand, this technique does not account directly for a number of factors which could play a primary role for the practical feasibility of the network. What if, for instance, once identified an optimal lay-out, we realize that some matches are hardly feasible in practice? Could we adapt the conventional pinch approach to keep into account site topological features since the preliminary design phase? In this paper the auth…

Bilevel heat exchanger network synthesis with an interactive multi-objective optimization method

2012

Abstract Heat exchanger network synthesis (HENS) has been an active research area for more than 40 years because well-designed heat exchanger networks enable heat recovery in process industries in an energy- and cost-efficient manner. Due to ever increasing global competition and need to decrease the harmful effects done on the environment, there still is a continuous need to improve the heat exchanger networks and their synthesizing methods. In this work we present a HENS method that combines an interactive multi-objective optimization method with a simultaneous bilevel HENS method, where the bilevel part of the method is based on grouping of process streams and building aggregate streams …