It is of great significance to study the ventilation characteristics of air supply systems in spillway tunnels, especially for high dams. In this paper, a brief theoretical approach to evaluate the ventilation characteristics of a multi-intake-well a...
In the long-distance thermal air heating process of large space buildings, there are common problems of thermal air trajectory deflection and low energy efficiency caused by thermal buoyancy. This study proposes an induced air supply system that is e...
As application of electric energy have expanded, the uninterruptible power supply (UPS) concept has attracted considerable attention, and new UPS technologies have been developed. Despite the extensive research on the batteries for UPS, conventional...
Buildings account for a large portion of the total energy use in the US; therefore, improving the operation of typical variable-air-volume (VAV) systems in buildings can provide a tremendous economic opportunity. ASHRAE Guideline 36 recommends a rese...
A variable refrigerant flow integrated stratum ventilation (VRF-SV) system was proposed as an energy efficient substitute for conventional central cooling systems for buildings. The novel system provided conditioned air to enclosed spaces with high i...
Water scarcity is an urgent issue for social and economic development in arid and semi-arid areas. Constructing long-distance pressurized water supply projects is a commonly used measure to solve water scarcity problems in these areas. With the incre...
As an important part of the fuel cell subsystem, the air supply system of the proton exchange membrane fuel cell (PEMFC) plays an important role in improving the output performance and durability of fuel cells. It is necessary to control the oxygen e...
This paper developed an algorithm that controls the supply air temperature in the variable refrigerant flow (VRF), outdoor air processing unit (OAP) system, according to indoor and outdoor temperature and humidity, and verified the effects after appl...
Façades built with integrated passive solar systems hold great promise for improving the energy performance of buildings and achieving indoor comfort conditions. Among these techniques, solar air preheating systems with different configuration...
This paper presents work intended to characterize air flow and convective heat transfers within a ventilated window. This window is a device that allows for the entry of fresh air into a building while simultaneously preheating it in order to satisfy...
Pressure differences in the envelope of a building result in leakage airflow (i.e., the unintended flow of air). This can lead to increased building heating and cooling energy, decreased thermal comfort for occupants, and the spread of moisture. To a...
Problems of low temperature, low pressure, low oxygen, and high carbon dioxide (CO2) concentration in the air-conditioning (AC) trains of the Qinghai-Tibet railway can affect the health and comfort of passengers and cause altitude sickness. When the...
Solar energy is the most available renewable resource and has great potential for various applications. Solar heat pumps are limited when operating alone due to weather and the unstable and intermittent nature of solar energy. The idea of combining a...
The aim of this research was to evaluate the effectiveness of phase-change materials (PCMs) incorporated into the supply air duct of a hollow-core slab ventilation system. Both experimental and numerical approaches were adopted in this investigation....
The progress of local environmental regulation in protected agriculture is sluggish, particularly concerning the local air supply, which poses a significant obstacle to greenhouse energy-saving research. This study establishes a test platform for loc...
The hydrogen fuel cell is a quite promising green device, which could be applied in extensive fields. However, as a complex nonlinear system involving a number of subsystems, the fuel cell system requires multiple variables to be effectively controll...
This article presents a field test of how deep renovation affects indoor climate quality. The studied apartment building was built in 1968 and is located in Finland, within the Nordic climate zone. The deep renovation included façade repair wi...
During the cold-start process of a PEMFC, the supply of air and hydrogen in the gas supply system has a great influence on the cold-start performance. The cold-start of a PEMFC is a complex nonlinear coupling process, and the traditional control stra...
In recent years, proton exchange membrane fuel cell (PEMFC) has received growing attention as a new sustainable energy source because of its high-power density and zero-emission. In the PEMFC system, the air supply control has a significant impact on...
Controls of a PEM fuel cell stack are one of the crucial issues for securing efficient and durable operations of the stack. When the air is excessively supplied, the efficiency of the system drops. Conversely, insufficient supply of the air causes ox...
Ventilation plays a key role in maintaining indoor air quality and reducing building-related symptoms (BRSs). Although prior studies suggest that ventilation volume and system type may influence BRSs, few have examined their combined effects in resid...
The integration of electric underfloor heating systems with photovoltaic (PV) panels presents a promising approach to enhance thermal efficiency and energy sustainability in residential heating. This study investigates the performance of such hybrid...
This study evaluates indoor thermal comfort and the energy performance of HVAC control strategies in the Congo Zone of a zoological facility located in Poland. The main objective in this zone is to maintain adequate relative humidity, which is more c...
Reasonable and effective control of a cathode air supply system is conducive to improving the dynamic response, operating efficiency, and reliability of fuel cell systems. This paper proposes a novel data-driven adaptive oxygen excess ratio (OER) con...
Spurred by the increasingly serious air pollution problem, the Chinese government has launched a series of policies to put forward specific measures of power structure adjustment and the control objectives of air pollution and coal consumption. Other...
Over the past 20 years, net-zero energy house (NZEH) construction costs have steadily decreased because of many reasons, such as technical progress, energy-saving design obligations, and dramatic cost reductions in renewable energy systems, especiall...
Firefighting foam is widely recognized for its excellent fire suppression performance. However, research on the effect of foam expansion ratio on the suppression efficiency of forest surface fires remains limited. In this study, the expansion ratio w...
The air–fuel ratio is a crucial parameter in internal combustion engines that affects optimal engine performance, emissions, fuel efficiency, engine durability, power, and efficiency. Positive pressure ventilators (PPVs) create specific operati...
The production of water in a drinking water supply system (WSS) comprises all drinking water enter in the net, while the consumption of water generally comprises all billed amounts of water in a WSS. The production and consumption of water in a drink...
There is a growing need to implement modern technologies, such as digital twinning, to improve the efficiency of transport fleet maintenance processes and maintain company operational capacity at the required level. A comprehensive review of the exis...
Rail transit as a high-energy consumption field urgently requires the adoption of clean energy innovations to reduce energy consumption and accelerate the transition to new energy applications. As an energy-saving fluid machinery, the ejector exhibit...
To increase system efficiency and power density, the cathode air path of Polymer Electrolyte Membrane Fuel Cells (PEM FCs) is supercharged using electrically driven air bearing centrifugal compressors. To maximize system efficiency, the cathode air s...
Proton exchange membrane fuel cells (PEMFC) are vulnerable to oxygen starvation when working under variable load. To address these issues, a cascade control strategy of sliding mode control (SMC) and Proportion Integration Differentiation (PID) contr...
This research investigates the use of phase change materials (PCMs) in thermal energy storage (TES) unit-based cooling systems to increase the efficiency of air conditioners (ACs) by reducing the air inlet temperature. This study aims to evaluate dif...
Demand is soaring for data centers with advanced data-processing capabilities. In data centers with high-temperature information technology (IT) equipment, enormous cooling systems are operated year-round. To date, studies have aimed to improve the c...
A Kalina cycle-based integration concept of municipal air-conditioning, electricity and gas is investigated thermodynamically, economically, and environmentally to reduce the carbon intensity of these supplies, with attention to hot climatic conditio...
To exploit the energy-saving potential of pneumatic actuator systems, various energy-saving circuits have been developed in recent decades. However, the principle of a pressure-based air supply cut-off has only been considered to a limited extent. Th...
Self-excited thermoacoustic instability (SETAI) is an undesirable and dangerous phenomenon in combustion systems. However, its control is difficult, thus greatly limiting the development of combustion technology. Our previous works clarified how the...
Driven by the urgent reduction in industrial energy consumption and nitrogen oxide (NOx) emissions, numerical simulation becomes a significant tool to understand the internal working process and optimize the structure of the combustion chamber in cok...
This study introduces a dynamic, multi-output stacking framework for real-time forecasting of HVAC cooling-coil behavior in air-handling units. The dynamic model encodes short-horizon system memory with input/target lags and rolling psychrometric fea...
As real-time indoor thermal data became available, the precision of the building thermal control systems has improved, but the use of resources has also increased. Therefore, it is imperative to examine the optimized point of energy use and thermal d...
Air valves are protective devices often used in pressurised water pipelines, ideally admitting air to limit sub-atmospheric pressures and controlling the release of entrapped air. This work summarises a comprehensive sensitivity analysis of the trans...
Decarbonization of the UK residential heating sector is crucial to cut the carbon emissions and meet the legal binding of the Climate Change Act, 2008. The current progress with residential building sector carbon neutrality is slow and, hence, accele...
In this paper, to maximize the net output power and realize better performance optimization and control of the oxygen excess ratio, a complete dynamic model of the proton-exchange membrane fuel cell system is developed and an active disturbance rejec...
The adoption of heat pumps in Ukraine is increasing, yet precise data on their economic viability are limited. This study compares the Levelized Cost of Heat (LCOH) in implemented and calculated heat pump systems under Ukrainian conditions. Analyzing...
Aim: This study aims to develop supply air jet models for split air conditioners. Background: Designing and operating an air conditioning system based on the unique characteristics of the supply air jet is essential to control the draft risk. Motivat...
There is currently no way for subway air-conditioning systems to adjust to changes in passenger capacity in terms of air-supply volume and air-supply temperature. In this paper, a study of the setting of the air-supply volume and controlling the temp...
The thermal environment of the development headings in deep underground mines tends to be harsh. The design of a reliable auxiliary ventilation system is an important strategy to maintain the thermal environment and air quality in the workplace. Henc...
Underfloor air distribution (UFAD) systems are increasingly used for their advantages in improving energy savings, indoor air quality, and thermal comfort. In UFAD systems, an underfloor plenum delivers conditioned air to the air supply diffusers. Th...
Precooling agricultural produce is an intensive, energy-consuming process. To improve the efficiency of forced-air precooling and ultimately contribute to energy sustainability for postharvest storage of fresh produce, we designed three alternative a...
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