scholarly journals Some aspects of controlling radiant and convective cooling systems

2019 ◽  
Vol 111 ◽  
pp. 05008 ◽  
Author(s):  
Taha Arghand ◽  
Jan-Olof Dalenbäck ◽  
Anders Trüschel ◽  
Saqib Javed
Keyword(s):  
Control System ◽  
Control Systems ◽  
Room Temperature ◽  
Energy Use ◽  
Cooling System ◽  
Pump Energy ◽  
Step Response ◽  
Feedback Signal ◽  
Cooling Systems ◽  
Heating And Cooling

Designing appropriate control systems for radiant heating and cooling terminals entails an understanding of their dynamic behaviour. This study experimentally investigates the dynamic response of a room with convective and radiant cooling systems. The experiments were performed in a 12.6 m2 large test room outfitted as a single-office room. The main cooling system was radiant ceiling panels which covered 70% of the ceiling area. The thermal performance of the radiant system was compared to that of a fan-coil unit (FCU). The results from the step response test showed that the time constant of the room for the radiant system was shorter than for the convective one, indicating faster changes in room temperature by the radiant system. Furthermore, controlling the FCU with similar control system tuned for ceiling panels increased the hysteresis gap in the room air temperature from 0.4 K to 0.8 K. This indicates that control systems for low-mass radiant systems and convective systems might be applied to each other, but on-site tuning is required to omit the offset (persistent error). In this study, controlling room temperature with ceiling panels did not benefit from using an operative temperature sensor to provide feedback signal to the control system. However, the pump energy use was moderately decreased by 14%.

scholarly journals Review of Intelligent Control Systems for Natural Ventilation as Passive Cooling Strategy for UK Buildings and Similar Climatic Conditions

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4388
Author(s):  
Esmail Mahmoudi Saber ◽  
Issa Chaer ◽  
Aaron Gillich ◽  
Bukola Grace Ekpeti
Keyword(s):  
Control Systems ◽  
Natural Ventilation ◽  
Energy Use ◽  
Integrated Control ◽  
Climatic Conditions ◽  
Effective Control ◽  
Practical Implementation ◽  
Optimal Output ◽  
Heating And Cooling ◽  
Building Cooling

Natural ventilation is gaining more attention from architects and engineers as an alternative way of cooling and ventilating indoor spaces. Based on building types, it could save between 13 and 40% of the building cooling energy use. However, this needs to be implemented and operated with a well-designed and integrated control system to avoid triggering discomfort for occupants. This paper seeks to review, discuss, and contribute to existing knowledge on the application of control systems and optimisation theories of naturally ventilated buildings to produce the best performance. The study finally presents an outstanding theoretical context and practical implementation for researchers seeking to explore the use of intelligent controls for optimal output in the pursuit to help solve intricate control problems in the building industry and suggests advanced control systems such as fuzzy logic control as an effective control strategy for an integrated control of ventilation, heating and cooling systems.

scholarly journals Analysis of heating and cooling periods in Budapest using station data

Időjárás ◽  
2021 ◽  
Vol 125 (3) ◽  
pp. 431-448
Author(s):  
Csenge Dian ◽  
Attila Talamon ◽  
Rita Pongrácz ◽  
Judit Bartholy
Keyword(s):  
Energy Use ◽  
Transitional Period ◽  
Design Parameters ◽  
Data Series ◽  
Total Energy Consumption ◽  
Regional Warming ◽  
Cooling Systems ◽  
Cooling Period ◽  
Heating And Cooling ◽  
The One

The built environment has a very complex role in cities. On the one hand, various urban climatological phenomena are caused and influenced by buildings (e.g., urban heat island effect, local wind conditions, air pollution). On the other hand, buildings are important contributors to energy use via heating and cooling, e.g. they account for about 40% of total energy consumption on average in Europe. Daily average outdoor temperature is taken into account to design the heating and cooling systems of residential, commercial, or office buildings. That is why we analyzed the available temperature time series of the capital of Hungary, Budapest for the period between 1901 and 2019. The aims of this study are (i) to investigate the changes in temperature data series that influence building energy design parameters, (ii) to analyze the heating and cooling periods in the last 119 years based on different definitions, and (iii) to define a third (transitional) period between the heating and cooling periods. Based on the results, it can be concluded that the variability of warm days is smaller than that of cold days, consequently, the optimal design of heating systems is a greater challenge compared to cooling systems. Furthermore, the length of the temperature-based heating period decreased substantially, while the length of the cooling period increased as a consequence of overall regional warming.

By-Pass Blending Station: An Innovative Secondary In-Building Pump System for District Heating and Cooling Systems

Solar Energy ◽  
2004 ◽  
Author(s):  
M. Liu ◽  
D. Barnes ◽  
K. Bunz ◽  
N. Rosenberry
Keyword(s):  
Distribution Systems ◽  
Pump Energy ◽  
District Heating ◽  
Water Systems ◽  
Pump System ◽  
Cooling Systems ◽  
Heating Systems ◽  
Heating And Cooling ◽  
Secondary Systems ◽  
Pump Head

An innovative secondary in-building pump system called the By-pass Blending Station (BBS) has been developed to reduce building pump energy consumption and maintain the desired return water temperatures in district heating and cooling systems. This method applies where district systems provide sufficient pump head for in-building water circulation. The BBS moves only the returned by-pass flow. Therefore, it uses less pump energy than the ASHRAE recommended method, which moves the entire building water flow by using in-building pump. The pump in the BBS is smaller than that of the ASHRAE recommended in-building secondary pump system. The BBS can be used in both constant and variable flow secondary systems. This paper compares the ASHRAE recommended secondary in-building pump with BBS systems using chilled water systems. The BBS only applies to cases where the primary distribution systems provide sufficient pump head for in-building circulation, which are typically found in commercial district cooling and heating systems.

scholarly journals Experimental Study to Performance Improvement of Vapor Compression Cooling System Integrated Direct Evaporative Cooler and Condenser

2018 ◽  
Vol 215 ◽  
pp. 01017
Author(s):  
Arfidian Rachman ◽  
Lisa Nesti
Keyword(s):  
Energy Use ◽  
Cooling System ◽  
Electricity Consumption ◽  
Weather Condition ◽  
Heat Removal ◽  
Cooling Capacity ◽  
Cooling Power ◽  
Cooling Systems ◽  
Evaporative Cooler ◽  
And Performance

For areas with very hot and humid weather condition increased latent and sensible load are a major problem in cooling systems that will increase compressor work so that electricity consumption will also increase. Combined condenser with direct evaporate cooling will increase the heat removal process by using an evaporative cooler effect that will increase the efficiency of energy use. This paper presents the study of the use of evaporator cooling and condenser. This paper mainly calculated energy consumption in steam compression cooling systems and related problems. From the results of this study, the use of condensers with evaporative cooling, power consumption can be reduced to 46% and performance coefficient (COP) can be increased by about 12%, with 1,2 kW cooling capacity.

scholarly journals Numerical investigation of the energy flexibility of different heating and cooling systems

2019 ◽  
Vol 111 ◽  
pp. 06001 ◽  
Author(s):  
Evangelia Loukou ◽  
Mingzhe Liu ◽  
Hicham Johra ◽  
Per Heiselberg ◽  
Bianca A. Dia ◽  
...  
Keyword(s):  
Energy Use ◽  
Numerical Study ◽  
Renewable Energy Sources ◽  
Heating System ◽  
Economic Benefits ◽  
Comfort Level ◽  
Grid System ◽  
Cooling Systems ◽  
Load Shifting ◽  
Heating And Cooling

The significant expansion of intermittent renewable energy sources can compromise the stability of energy grids due to the mismatch between instantaneous energy use and production. Buildings have a large potential for energy storage and demand-side management, which can offer energy flexibility to a Smart Grid system. Smart control of heating, ventilation and air conditioning systems is a great solution for improving flexible energy use, load shifting and power peak shaving. This numerical study compares the energy flexibility potential of three different heating and cooling systems implemented in a nearly zero-energy office building. The energy flexibility strategy consists in the modulation of heating / cooling indoor temperature set points according to an energy price signal. The energy flexibility assessment was performed based on the energy shifting ability, indoor thermal comfort level and economic benefits. This article establishes a better understanding of the flexibility potential of common and innovative heating / cooling technologies. Lindab Solus system has the highest load shifting ability with a flexibility index of 67.41%, followed by the radiator heating system, scoring a 59.92%, and the underfloor heating system with 56.65%. It is clear that the selection between different heating/ cooling systems can have a great impact on the energy flexibility of the grid system.

scholarly journals PROTOTYPE PENGENDALIAN DAYA LISTRIK AC DAN LAMPU DENGAN ANALISIS STANDAR KENYAMANAN RUANGAN BERBASIS ATMEGA 2560

2018 ◽  
Vol 5 (2) ◽  
pp. 263
Author(s):  
Made Dwi Krisna Putra Sudiharta ◽  
I Gede Dyana Arjana ◽  
Cok Gede Indra Partha
Keyword(s):  
Control System ◽  
Light Intensity ◽  
Temperature Sensor ◽  
Room Temperature ◽  
Electrical Energy ◽  
Ultrasonic Sensor ◽  
Cooling Systems ◽  
Air Conditioners ◽  
Lighting Control ◽  
Room Lighting

The use of air conditioners (AC) and lighting that do not suit the needs and excessive results in a lack of comfort and high use of electrical energy. Ultrasonic Sensor of SRF-04 functions to find out the number of people in the room, temperature sensor of DHT 22 functions to calculate the temperature and humidity inside and outside the room, Light Intensity sensor of GY-302 functions to read the level of light intensity in the room and micro controller of Arduino Mega 2560 functions to process all input sensors become the command for operating the AC units and lights. The AC and lighting control system working well and can determine the time and number of AC and light that is needed. Those are based by Indonesian room comfort standards so that it can increase the comfort of the room in terms of cooling systems and room lighting with a temperature of 22oC to 25 oC and light intensity of 300 lux.

Active Thermal Regulation Systems for Footwear: Development of New Innovative Technologies

2021 ◽  
Vol 893 ◽  
pp. 57-63
Author(s):  
João Ferraz ◽  
Sónia Silva ◽  
Helena Fernandes ◽  
Sarah Bogas ◽  
Bruno Vale ◽  
...  
Keyword(s):  
Cooling System ◽  
Heating System ◽  
Thermal Dissipation ◽  
Thermal Regulation ◽  
Peltier Effect ◽  
Cooling Systems ◽  
Heating And Cooling ◽  
Peltier Modules ◽  
Technological Challenge ◽  
Printing Techniques

This work aims to develop safety shoes, with thermal regulation systems, namely innovative heating and cooling systems. Heating system was developed using printing techniques; and cooling system was developed using the integration of Peltier modules in the shoe structure. These materials are based on the Peltier effect, in which, when an electric current is applied, the heat moves from one face to the other, being subsequently removed using thermal dissipation methods. This effect allows an active cooling. Given the high technological challenge of integrating cooling systems into footwear, this paper will present only developments related to cooling system.

scholarly journals Energy consumption and modelling of the climate control system in the electric vehicle

2018 ◽  
Vol 37 (1) ◽  
pp. 519-543 ◽  
Author(s):  
Aisling Doyle ◽  
Tariq Muneer
Keyword(s):  
Control System ◽  
Energy Consumption ◽  
Electric Vehicle ◽  
Waste Heat ◽  
Cooling System ◽  
Weather Conditions ◽  
Mean Bias Error ◽  
Space Heating ◽  
Climate Control ◽  
Heating And Cooling

With the introduction of electric vehicles in the automobile market, limited information is available on how the battery’s energy consumption is distributed. This paper focuses on the energy consumption of the vehicle when the heating and cooling system is in operation. On average, 18 and 14% for the battery’s energy capacity is allocated to heating and cooling requirements, respectively. The conventional internal combustion engine vehicle uses waste heat from its engine to provide for passenger thermal requirements at no cost to the vehicle’s propulsion energy demands. However, the electric vehicle cannot avail of this luxury to recycle waste heat. In order to reduce the energy consumed by the climate control system, an analysis of the temperature profile of a vehicle’s cabin space under various weather conditions is required. The present study presents a temperature predicting algorithm to predict temperature under various weather conditions. Previous studies have limited consideration to the fluctuation of solar radiation space heating to a vehicle’s cabin space. This model predicts solar space heating with a mean bias error and root mean square error of 0.26 and 0.57°C, respectively. This temperature predicting model can potentially be developed with further research to predict the energy required by the vehicle’s primary lithium-ion battery to heat and cool the vehicle’s cabin space. Thus, this model may be used in a route planning application to reduce range anxiety when drivers undertake a journey under various ambient weather conditions while optimising the energy consumption of the electric vehicle.

Two Papers on Engine Cooling First Paper: The Cooling of Diesel Engines by Water under Pressure

1966 ◽  
Vol 181 (1) ◽  
pp. 105-114
Author(s):  
J. Gratzmuller ◽  
S. J. Davies
Keyword(s):  
Diesel Engines ◽  
Cooling System ◽  
Lubricating Oil ◽  
Standard Equipment ◽  
Cooling Systems ◽  
Engine Cooling ◽  
Heating And Cooling ◽  
In Series ◽  
High Static Pressure ◽  
Cooling Air

Water cooling in diesel engines is studied, with particular reference to the application of these engines in locomotives of high power. In this context, problems relating to weight, volume and radiator design become progressively more difficult to solve with the tendency towards increased unit powers. In the solution considered the water in the cooling system is put under a high static pressure, which makes it possible to raise the water temperatures above the usual levels. Resulting from this, the formation of steam bubbles is reduced or eliminated, ‘cavitation corrosion’ is reduced considerably, and cavitation in the water pump is prevented. Water consumption is markedly reduced. Standard equipment for locomotives is described. Cooling the supercharge air and the lubricating oil at relatively low temperatures is compatible with cooling the engine at a high temperature if two cooling circuits are used, with their radiators placed in series in the cooling air current. The case of cooling engines of high supercharge is examined; in these, the heat taken from the admission air and from the lubricating oil exceeds that taken from the engine. Future designs of heating and cooling systems for engines with very high supercharge are proposed.

The Approach for Analyzing Motion Mode of High-Order Control Systems

2014 ◽  
Vol 596 ◽  
pp. 594-597
Author(s):  
Sheng Guo Zhang ◽  
Kai Wang ◽  
Xiao Ping Dang
Keyword(s):  
Control System ◽  
Modal Analysis ◽  
Control Systems ◽  
High Order ◽  
Step Response ◽  
Space Theory ◽  
Analysis Method ◽  
Inverse Laplace Transformation ◽  
State Space Theory ◽  
Motion Mode

This paper aims at exploring the modal analysis approach of a motion control system. Based on the inverse Laplace transformation, the step response of a control system is derived. Then this response is associated with the modal analyses in state space theory. And then the motion mode of a control system is analyzed with the modal analysis method. Application example indicates that this approach can be used to analyze the high-order control system successfully. This facilitates the motion mode analyses of high-order control system very much.

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