1,027 Results Found

In this paper, we introduce and study proximal $\mathfrak{Z}$-condensing operators in strictly convex Banach spaces by combining simulation functions with measures of noncompactness. A Darbo-type best proximity point theorem is established, and several consequenc...

Previous studies have been conducted by employing various methods to reduce the condenser water temperature, a crucial control variable to consider when attempting to improve the operational efficiency of a chiller. The existing literature dealing wi...

Non-equilibrium condensation involves intricate physics, making it crucial to thoroughly investigate the factors that influence it. Understanding these factors is essential for optimizing the system performance and minimizing the negative effects ass...

Increasing number of refrigeration units has led to an increase of CO₂ emissions and the destruction of the ozone layer. Using low global warming potential (GWP) refrigerants, improving the efficiency of vapour compression refrigeration (VCR) units,...

We present a survey of the theory of measures of noncompactness and discuss some fixed point theorems of Darbo’s type. We apply the technique of measures of noncompactness to the characterization of classes of compact operators between certain...

An experimental rig of a zeotropic mixture separation condensation-based dual-temperature refrigeration cycle is built and the mixture R290/R600a is used as the refrigerant. Compared with a conventional cycle, the proposed refrigeration system demons...

With the rapid development of renewable energy in China, thermal power units are facing decommissioning issues, while the power system is confronted with severe challenges such as reduced grid strength and insufficient voltage support. For power syst...

In this research paper, we investigate the controllability in the $\alpha$-norm of a coupled system of integrodifferential equations with state-dependent nonlocal conditions in generalized Banach spaces. We establish sufficient conditions for the syst...

Under conditions of gradual depletion of gas-condensate field reserves and declining well production rates, one of the key challenges in operating offshore production facilities is improving the energy efficiency and reliability of process equipment,...

A DC power support strategy utilizes the flexibility of a High-voltage direct-current (HVDC) system in power modulation to optimize the operating point or compensate the power imbalance caused by a disturbance. The major impediment to the strategy is...

In this paper, we deal with the delayed measure differential equations with nonlocal conditions via measure of noncompactness in ordered Banach spaces. Combining $(\beta ,{\gamma }_k)$-resolvent family, regulated functions and fixed point theorem with res...

We obtained results on the existence and uniqueness of a mild solution for a fractional-order semi-linear differential inclusion in a Hilbert space whose right-hand side contains an unbounded linear monotone operator and a Carathéodory-type mu...

Proton exchange membrane fuel cells are a promising technology for future transportation applications. However, start-up procedures that are not optimized for low temperatures can lead to the early failure of the cells. Detailed CFD models can suppor...

Aviation soot constitutes a significant threat to human well-being, underscoring the critical importance of accurate measurements. The condensation particle counter (CPC) is the primary instrument for quantifying aviation soot, with detection efficie...

Following the international trend of using hydrogen as combustible in many industry branches, this paper investigates the impact of mixing methane gas with 23% hydrogen (G222) on condensing boilers’ operation. After modeling and testing several...

The paper investigated the problem of selecting/finding the optimal process conditions for gas condensate wells. The well process conditions imply a set of parameters that characterize its operation. The optimization of process conditions provides fo...

This paper introduces a novel class of condensing mappings through the concept of $\alpha$-admissibility. We prove several extensions of Darbo’s fixed point theorem within this framework, including a generalized contractive condition and a coupl...

In absorption systems using the aqueous lithium bromide mixture, the Coefficient of Performance is affected by the desorber. The main function of this component is to separate the refrigerant fluid from the working mixture. In conventional boiling de...

Generators and condensers are the two vital equipment items that determine the output of vapor absorption refrigeration systems. Arid weather conditions produce a significant reduction in the performance of the vapor absorption refrigeration cycle du...

The paper presents a numerical analysis of a tube-in-tube condenser of a small refrigeration system. One of the challenges in designing such units is to reduce their dimensions while maintaining the highest possible cooling capacity, so the research...

We formulate a more straightforward, symmetry-based technique for manually computing the determinant of any $n\times n$ matrix by revisiting Dodgson’s condensation method, as well as strategically applying elementary row (column) operat...

Considering the advantages that dynamic reactive power (var) equipment (such as synchronous condensers (SCs), which can control var independently and improve voltage stability), SCs are widely used in AC/DC hybrid power grid to provide emergency var...

This study evaluated polyhydroxyalkanoates (PHAs) production from a medium corresponding to the condensate derived from food waste drying, using a mixed microbial culture in a 15 L Sequencing Batch Reactor (SBR). The reactor operation comprised two d...

We propose an approach to constructing semiclassical solutions for the generalized multidimensional Gross–Pitaevskii equation with a nonlocal interaction term. The key property of the solutions is that they are concentrated on a one-dimensional...

We propose the approach to constructing semiclassical spectral series for the generalized multidimensional stationary Gross–Pitaevskii equation with a nonlocal interaction term. The eigenvalues and eigenfunctions semiclassically concentrated on a cur...

The characteristics of a mechanical structure under operating conditions may differ from those in a static state. It is often more desirable to obtain the frequency response function (FRF) of the operating structure in engineering applications. While...

This paper discusses two measures of non-p-convexity and aims to develop them for applications in p-normed spaces. We also extend and generalize some important properties and well-known results.

In this study, several purge and ventilation methods are proposed to reduce and remove condensation in a heat recovery ventilator for commercial and household buildings. The effects of the airflow rate, duration of ventilation, purge interval, and re...

The transient characteristics of pressure in the condenser under fault conditions have a crucial impact on the safe operation of the entire nuclear power plant. In order to ascertain whether the condenser pressure of a HPR1000 nuclear power unit meet...

In Europe, primary energy consumption in buildings accounts for up to 25–40%, depending on the climate conditions. Space heating and Domestic Hot Water (DHW) contribute significantly to this energy consumption. Among the most common sources for heat...

Inter-turn short circuit in the excitation windings of synchronous condensers is a common fault that directly impacts their normal operation. However, current fault analysis and diagnosis of synchronous condensers primarily rely on voltage-balanced c...

Water condensation is a possible cause of membrane wetting in the operation of membrane contactors, especially under high-temperature conditions. In this study, water condensation in pores of polytetrafluoroethylene (PTFE) hollow fiber membranes was...

This is an experimental work performed to identify the influence of direct contact condensation inside an eductor. The fluid used in the experiments is water in two different phases: liquid and vapor, for primary and secondary flows, respectively. Th...

To improve the adaptability of direct air-cooled power generating units to the variations of both meteorological condition and power load, a piping-main arrangement of air-cooled condensers was proposed. The heat and mass transfer models of the air-s...

Road tunnel ventilation systems have traditionally been designed to dilute vehicle-generated pollutants and control smoke during fires. However, the thermal environment, including temperature and humidity, is not the variable taken into consideration...

Shell-and-tube falling film condensers are critical in fields like energy, petrochemicals, and waste heat recovery. Their operation predominantly involves the complex mixed condensation of steam and non-condensable gases. This process couples multi-p...

Apples are stored at temperatures close to 0 °C and high relative humidity (up to 95%) under controlled atmosphere conditions. Under these conditions, the cyclic operation of the refrigeration machine and the associated temperature fluctuations c...

This paper provides the results of experimental investigations of the exemplary mini-channel heat exchanger in its application as a condenser and an evaporator in a compressor refrigeration system with propane as a working fluid. The aim of the inves...

For absorption cooling cycles using water as a refrigerant, H₂O/LiCl mixtures are suitable for replacing conventional H₂O/LiBr mixtures. In addition, membrane devices can be used to develop compact and lighter absorption systems, and they can operate...

The article examines the problems associated with the use of waste thermal energy. A new concept is developed on how to improve an atmospheric condensing engine by using low-temperature waste thermal energy, converting it into energy acceptable to th...

Condensation assessment of a residential building in Changsha, China-located in the hot summer and cold winter climate zone-was conducted during the Plum Rain Season (PRS) using Energy Plus simulations and field measurements. Window-opening behaviour...

In order to obtain a high-accuracy and adaptable condensation phase change model, this paper selects the Nusselt number correlation formula that Kim proposed based on the experimental data and adjusts the Nusselt number in the bubble condensation pro...

To address insufficient dynamic reactive power support during large-scale new energy grid connection, synchronous condensers are widely used in centralized new energy delivery. As a special rotating electrical machine, their operational stability is...

This work reviews the current operational condition and activities on design modification for different applications of ejectors. Ejectors being a simple mechanical system capable of performing multiple fluid related functions (vacuum generation, pum...

This study focuses on modeling and dynamic identification of a reflux condenser in a batch reactor system. The model uses data from real industrial conditions, along with the Volterra series and Genocchi orthogonal polynomials, to capture the condens...

The growing global demand for energy and the costly taxes on electric energy demonstrate the importance of seeking new techniques to improve energy efficiency in industrial facilities. Refrigeration units demand a large amount of electricity due to t...

In a previous work, a solar chimney power plant integrated with a solid sorption cooling system for power and cold cogeneration was developed. This prior work showed that reusing the heat released from the adsorption bed enhances the system’s u...

Concentrated solar power systems can provide dispatchable renewable energy, but their application in distributed cogeneration is constrained by high costs and thermal losses associated with indirect heat transfer. This study proposes a direct vapour...

Cogeneration power plants have already been operated in the Czech Republic for several decades. These cogeneration power plants have been mostly operated with original technologies. However, these original technologies have to be continuously innovat...

Condensation in a building encourages microbial growth, which can have an adverse effect on the health of occupants. Furthermore, it induces the deterioration of the building. To prevent problems caused by condensation, from the design step of a buil...