Effect Of The Water Inlet Temperature And Flow Rate On The Energy And Exergy Performance of A Forced Draft Counter Wet Cooling Tower

Abstract Cooling towers, wherein water and air are contacted directly with each other, are specialized heat exchangers. These open-topped, tall, cubical or cylindrical shaped are responsible for reducing the temperature of the water that generated from the industrial or HVAC systems. The performance of the forced draft wet cooling tower is investigated experimentally. The performance analysis is based on the first and second law of thermodynamics. The impact of the inlet water temperature and water inlet flow rate is investigated. The inlet water temperature is varied from 28 °C to 42 °C for the water flow rates of (0.03, 0.05 and 0.075 kg/sec). The results reveal that the cooling capacity, cooling range, thermal efficiency and the total exergy destruction increase according to the increase in the inlet water temperature and the water flow rate. The maximum cooling range is found to be 14.8 °C with the maximum thermal efficiency of 74 %. On other hand, the exergy efficiency decreases with the increasing of the inlet water temperature and the water flow rate within a range of 11.9 % to 57.8 %.

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Experimental Investigation on Improvement of Wet Cooling Tower Efficiency with Diverse Packing Compaction Using ANN-PSO Algorithm

Energies ◽

10.3390/en14010167 ◽

2020 ◽

Vol 14 (1) ◽

pp. 167

Author(s):

Hasan Alimoradi ◽

Madjid Soltani ◽

Pooriya Shahali ◽

Farshad Moradi Kashkooli ◽

Razieh Larizadeh ◽

...

Keyword(s):

Neural Network ◽

Water Temperature ◽

Water Flow ◽

Flow Rate ◽

Cooling Tower ◽

Air Flow ◽

Water Flow Rate ◽

Pso Algorithm ◽

Outlet Temperature ◽

Air Flow Rate

In this study, a numerical and empirical scheme for increasing cooling tower performance is developed by combining the particle swarm optimization (PSO) algorithm with a neural network and considering the packing’s compaction as an effective factor for higher accuracies. An experimental setup is used to analyze the effects of packing compaction on the performance. The neural network is optimized by the PSO algorithm in order to predict the precise temperature difference, efficiency, and outlet temperature, which are functions of air flow rate, water flow rate, inlet water temperature, inlet air temperature, inlet air relative humidity, and packing compaction. The effects of water flow rate, air flow rate, inlet water temperature, and packing compaction on the performance are examined. A new empirical model for the cooling tower performance and efficiency is also developed. Finally, the optimized performance conditions of the cooling tower are obtained by the presented correlations. The results reveal that cooling tower efficiency is increased by increasing the air flow rate, water flow rate, and packing compaction.

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Experimental Research on Heat Transfer of Closed Cooling Tower with Packing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.960-961.614 ◽

2014 ◽

Vol 960-961 ◽

pp. 614-620 ◽

Cited By ~ 1

Author(s):

Ya Su Zhou ◽

Xiao Ding ◽

Wei Xie

Keyword(s):

Water Flow ◽

Flow Rate ◽

Cooling Tower ◽

Water Flow Rate ◽

Cooling Water ◽

Cocurrent Flow ◽

Inlet Temperature ◽

Cooling Performance ◽

Cooling Water Flow Rate ◽

Better Than

Three different structural types of closed cooling tower (CCT) and two cooling water flow directions were considered. The experimental study were done on the cooling performance of influences of inlet air dry and wet bulb temperature, cooling water flow rate and inlet temperature, air flow rate and spray density. The experimental results show that the cooling performance of CCT with packing is obviously better than non-packing cooling tower in 7%~18.4%. And the cooling performance of CCT with packing on top and coil underneath is slightly better than CCT with coil on top and packing underneath in 4.9%. In the same conditions the cooling performance of CCT with packing under cooling water cocurrent-flow is better than that cooling water countercurrent-flow in 3.2%~9.6%. Therefore, the closed cooling tower structure with the cooling water path in bottom and out top, and with packing on top and coil underneath is recommended.

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Analysis of Loss-of-Flow Accidents in Pre-Cooler and Inter-Cooler of HTR-10GT

ASME 2018 Nuclear Forum ◽

10.1115/nuclrf2018-7381 ◽

2018 ◽

Author(s):

Xiaoyong Yang ◽

Xiao Li ◽

Jie Wang ◽

Youjie Zhang

Keyword(s):

Water Temperature ◽

Water Flow ◽

Flow Rate ◽

Heat Exchangers ◽

Power Conversion ◽

Water Flow Rate ◽

Inlet Temperature ◽

Brayton Cycle ◽

Reactor Inlet ◽

Conversion System

Closed Brayton cycle (CBC) coupled with High Temperature Gas-cooled Reactor (HTGR) has potential application due to its compact configuration, high power generation efficiency and inherent safety. It is also one of the major power conversion methods for Generation IV advanced nuclear power systems. The typical CBC has several helium-water heat exchangers, including pre-cooler and inter-cooler. These helium-water heat exchangers have important influence on the performance of power conversion system, especially in loss-of-flow accidents (LOFAs). A system model including the reactor and the energy conversion system was established in this paper. The 10MW High Temperature Gas-cooled reactor-test Module helium Gas Turbine (HTR-10GT) was taken as the example to show the consequences of LOFAs. The results showed that LOFAs led to the rising of water temperature out of heat exchangers. With the reduction of water flow rate, the maximum water temperature would increase sharply, and the water temperature in pre-cooler was higher than that in inter-cooler. At low water flow rate, the water temperature would exceed the boiling point. LOFAs also made the rising of helium temperature. It had impacts on the performance of helium compressors. The elevated inlet temperature of helium compressors changed the corrected speed and corrected flow rate, therefore caused the deterioration of compressor’s performance. Furthermore, the LOFAs caused the reactor inlet temperature increasing. In low water flow rate, it would make the reactor inlet temperature beyond the temperature limitation of reactor pressure vessel and influence the safety of reactor. And the LOFAs also reduced the output work of cycle. This paper provides insights of features of CBC in LOFAs and will be helpful to the design and safety operation of closed Brayton cycle coupled with HTGR.

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Using a Novel Phase Change Material-Based Cooling Tower for a Photovoltaic Module Cooling

Journal of Solar Energy Engineering ◽

10.1115/1.4044890 ◽

2019 ◽

Vol 142 (2) ◽

Cited By ~ 1

Author(s):

Nasrin Abdollahi ◽

Masoud Rahimi

Keyword(s):

Surface Temperature ◽

Phase Change ◽

Phase Change Material ◽

Output Power ◽

Water Flow ◽

Flow Rate ◽

Cooling Tower ◽

Water Flow Rate ◽

Helical Tube ◽

Change Material

Abstract This paper presents an experimental investigation on a hybrid solar system, including a water-based photovoltaic (PV) solar module and a phase change material (PCM)-based cooling tower, for cooling of the module. Elimination of heat from the PV module was performed by the use of water in the back of the panel. The PCM-based cooling tower was used as a postcooling system. A composite oil consisting of 82 wt% coconut oil and 18 wt% sunflower oil has been used as a novel phase change material in the cooling tower. The helical tubes of the cooling tower were fabricated in two different curvature ratios of 0.054 and 0.032. The experiments were performed at three different water flow rates of 11.71, 16.13, and 19.23 mL/s. The cooling performance evaluation was carried out using the average surface temperature and output power of the photovoltaic panel. The results indicated that diminution of the average PV surface temperature relative to the reference temperature was 34.01 and 32.36 °C at a water flow rate of 19.23 mL/s for the cooling systems with helical tube curvature ratios 0.054 and 0.032, respectively. Furthermore, the highest electric output power was achieved for the cooling system with a helical tube curvature ratio of 0.054 at a water flow rate of 19.23 mL/s.

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Experimental Study on the Desalination System Using Humidification-Dehumidification Technology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1008.177 ◽

2020 ◽

Vol 1008 ◽

pp. 177-185

Author(s):

Hamed Abbady ◽

Mahmoud Salem Ahmed ◽

Hamdy Hassan ◽

A.S.A. Mohamed

Keyword(s):

Water Temperature ◽

Water Flow ◽

Flow Rate ◽

Water Flow Rate ◽

Cooling Water ◽

Operating Conditions ◽

Outlet Temperature ◽

Major Objective ◽

Cooling Water Flow Rate ◽

Output Ratio

In this paper, an experimental work studies the principal operating parameters of a proposed desalination process using air humidification-dehumidification method. The major objective of this work is to determine the humid air behavior through the desalination system. Different operating conditions including the effect of the water temperature at the entry to the humidifier, the ratio of the mass of water to the air, the air/water flow rate, and cooling water at entry the dehumidifier on the desalination performance were studied. The results show that the freshwater increases with increasing the water temperature at the inlet of the humidifier, the ratio of the mass of water to air, and cooling water flow rate in the dehumidifier. Cooling water outlet temperature at the condenser increases with increasing the water temperature at humidifier inlet. Also, it decreases as increasing cooling water flow rate while the ratio of the mass of water to air achieves the highest productivity and gained output ratio (GOR). The achieved mass ratio (MR) is 4.5 and the mass flow rate of air is 0.8 kg/min.

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ANALISIS EKSPERIMEN LAJU ALIRAN VOLUME AIR TERHADAP TEMPERATUR AIR PANAS PADA HEAT RECOVERY SISTEM AC JENIS WATER CHILLER

Dinamika Teknik Mesin ◽

10.29303/d.v1i2.118 ◽

2011 ◽

Vol 1 (2) ◽

Author(s):

I Made Rasta

Keyword(s):

Water Temperature ◽

Water Flow ◽

Flow Rate ◽

Heat Recovery ◽

Tap Water ◽

Water Flow Rate ◽

Maximum Heat ◽

Heating Water ◽

Compressor Work ◽

Heat Released

Refrigerant in refrigeration machines will absorb heat from a room space and released the heat to the environment. The heat balancing in the system is heat released from condenser equal with heat absorbed from room space added by the heat equivalent from compressor work. Based on this heat cycle, the writer try to conduct research on using this heat rejection from condenser to heating tap water, focusing on water flow rate increased from 0.5 liter/min to 2.5 liter/min. From experiment and analysis result obtained that the maximum heat water temperature which can be reached is 47.5°C in 0.5 liter/min, with the equipment specifications are 2 HP- split air conditioning and the tank volume is 75 liters. The additional result is heating water temperature is fallen when the water flow rate is increased.

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Analysis of the impact of water flow rate of selected Turbo type nozzle on the distribution of sprinkling intensity

The proceedings of the 13th international conference "Modern Building Materials, Structures and Techniques" (MBMST 2019) ◽

10.3846/mbmst.2019.076 ◽

2019 ◽

Author(s):

Jerzy Gałaj ◽

Tomasz Drzymała ◽

Adam Pełech ◽

Ritoldas Šukys

Keyword(s):

Water Flow ◽

Flow Rate ◽

Water Flow Rate ◽

Fire Service ◽

Graphical Form ◽

Operating Pressure ◽

Nozzle Outlet ◽

Maximum Value ◽

Trade Name ◽

The Impact

In the work, the distribution of the sprinkling intensity for a selected nozzle with the trade name Turbomatic was tested and analysed. The device meets Polish legal requirements, has a CNBOP approval certificate and is classified as a TURBO type nozzle. The research was aimed at extending the knowledge about spray jets generated by nozzles, in particular analysing the impact of water flow rate on selected parameters of the sprinkling surface. These dependencies can in practice save water and more effectively extinguish during rescue and firefighting operations. The tests were carried out in the laboratory of the Rescue and Fire-Fighting Equipment of the Main School of Fire Service partly in field conditions. Two different water flow rates of 200 and 400 dm3/min were assumed at a set operating pressure at the nozzle outlet of 0.4 MPa. The position and methodology of conducted research was discussed. Selected results were presented in tabular and graphical form. Their analysis was carried out and conclusions were made based on it. They shows that the flow rate of the nozzle has a significant impact on sprinkling surface parameters such as: its size and shape, range projection, maximum value of sprinkling intensity, location of maximum, etc.

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An experimental investigation on the coefficient of performance of the small hot water heat pump using refrigeration R410A and R32

Science & Technology Development Journal - Engineering and Technology ◽

10.32508/stdjet.v3i2.676 ◽

2020 ◽

Vol 3 (2) ◽

pp. First

Author(s):

Le Minh Nhut ◽

Tran Quang Danh

Keyword(s):

Ambient Temperature ◽

Water Temperature ◽

Water Flow ◽

Heat Pump ◽

Flow Rate ◽

Water Flow Rate ◽

Hot Water ◽

Coefficient Of Performance ◽

Electric Heater ◽

Initial Water

Hot water is an important factor in domestic life and industrial development. Today, the heat pump is used to produce hot water more and more popular because it has many advantages of saving energy compared to the method of producing hot water by the hot water electric heater. The main aim of this study is to evaluate of the coefficient of performance (COP) of the small hot water heat pump using refrigeration R410A and R32. The capacity of both hot water heat pump is similar, one using new refrigerant R32 and other using refrigerant R410A. These heat pumps were designed and installed at the Ho Chi Minh City University of Technology and Education to evaluate the COP for the purpose of application the new refrigerant R32 for hot water heat pump. The compressor capacity is 1 Hp, the volume of hot water storage tank is of 100 liters and is insulated with thickness of 30 mm to reduce the heat loss to invironment, the required hot water temperature at the outlet of condenser is 50 oC, and the amount of required hot water is 75 liters per batch and is controlled by float valve. The experimental results indicate that the COP of the heat pump using the new refrigerant R32 is higher than heat pump using refrigerant R410A from 9% to 15% when the experimental conditions such as ambient temperature, initial water flow rate through the condenser and the required temperature of hot water were the same. In addition, the effect of the ambient temperature, initial water temperature and water flow rate were also evaluated.

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