Experimental thermal study of ice slurry production system equipped with direct contact heat exchanger and spiral nozzle

2020 ◽  
pp. 1-27
Author(s):  
Yaokang Zhang ◽  
Lin Su ◽  
Zhaoyang Xu ◽  
Kaijun Dong ◽  
Jing Li
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Production System ◽  
Direct Contact ◽  
Water Flow Rate ◽  
Production Performance ◽  
Ice Slurry ◽  
Internal Water ◽  
System Pressure ◽  
Ice Production

Abstract For direct contact ice slurry production system, the obstacles of ice blockage in the nozzle, enormous refrigerant charge and refrigerant-water separation restrict its commercial application. In this paper, a novel direct contact ice slurry production system is proposed to overcome these obstacles. In this novel system, the horizontal PVC pipe with spiral nozzle is designed as a direct contact ice slurry generator to avoid ice blockage in the nozzle. The two phase RC318 is utilized as the system refrigerant. In order to investigate the ice production performance of this novel system, the effects of compressor rotational speed, internal water flow rate and initial system pressure on ice production performance are experimentally studied, and a lump model is established. The results show that the ice production performance is mainly affected by the compressor rotational speed, but scarcely affected by the internal water flow rate. However, large ice blocks are formed at small internal water flow rate. Besides, the lump model is considered to be able to predict the water temperature. Furthermore, the sinking of liquid refrigerant exits under the higher initial system pressure, but it can be avoided by reducing the initial system pressure.

scholarly journals To Combine or Not To Combine An In-Depth Review of Standard and Combined Hydronic Systems and Their Various Pitfalls

1993 ◽  
Vol 10 (2) ◽  
Author(s):  
Edward W. Saltzberg
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Water Flow Rate ◽  
Heating System ◽  
Hot Water ◽  
Space Heating ◽  
System Pressure ◽  
Hot Water Supply ◽  
Heating Boiler

A hydronic heating system is simply a piping arrangement conveying hot water to heat exchangers in order to provide space heating. A conventional hydronic heating system usually delivers hot supply water at 180 to 200 Fahrenheit temperature and has a dedicated space heating boiler. The hot water return temperature is usually about 140 Fahrenheit, meaning a 40 to 60 temperature difference between supply and return. The conventional hydronic heating system has a relatively constant circulated water flow rate and the temperature of the delivered hot water supply can be reset from outside air temperature. The water flow balancing of a conventional hydronic heating system is somewhat straightforward, although quite critical. The pipe sizing is determined on the basis of gallons per minute flow rate, the selected system pressure drop, and the maximum prudent velocity for the specific piping material. The circulating pump is selected on the basis of the required gallons per minute

scholarly journals Effect of Water Flow on Underwater Wet Welded A36 Steel

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 682
Author(s):  
Eko Surojo ◽  
Aziz Harya Gumilang ◽  
Triyono Triyono ◽  
Aditya Rio Prabowo ◽  
Eko Prasetya Budiana ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Physical And Mechanical Properties ◽  
Shielded Metal Arc Welding ◽  
Effect Of Water ◽  
Bending Effect ◽  
Metal Arc Welding ◽  
A36 Steel

Underwater wet welding (UWW) combined with the shielded metal arc welding (SMAW) method has proven to be an effective way of permanently joining metals that can be performed in water. This research was conducted to determine the effect of water flow rate on the physical and mechanical properties (tensile, hardness, toughness, and bending effect) of underwater welded bead on A36 steel plate. The control variables used were a welding speed of 4 mm/s, a current of 120 A, electrode E7018 with a diameter of 4 mm, and freshwater. The results show that variations in water flow affected defects, microstructure, and mechanical properties of underwater welds. These defects include spatter, porosity, and undercut, which occur in all underwater welding results. The presence of flow and an increased flow rate causes differences in the microstructure, increased porosity on the weld metal, and undercut on the UWW specimen. An increase in water flow rate causes the acicular ferrite microstructure to appear greater, and the heat-affected zone (HAZ) will form finer grains. The best mechanical properties are achieved by welding with the highest flow rate, with a tensile strength of 534.1 MPa, 3.6% elongation, a Vickers microhardness in the HAZ area of 424 HV, and an impact strength of 1.47 J/mm2.

Experimental Characterization of a Modified Airlift Pump

2014 ◽  
Author(s):  
Afshin Goharzadeh ◽  
Keegan Fernandes
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
High Speed ◽  
Water Flow Rate ◽  
High Speed Photography ◽  
Two Phase ◽  
Inner Diameter ◽  
Airlift Pump ◽  
Flow Map ◽  
Churn Flow

This paper presents an experimental investigation on a modified airlift pump. Experiments were undertaken as a function of air-water flow rate for two submergence ratios (ε=0.58 and 0.74), and two different riser geometries (i) straight pipe with a constant inner diameter of 19 mm and (ii) enlarged pipe with a sudden expanded diameter of 19 to 32 mm. These transparent vertical pipes, of 1 m length, were submerged in a transparent rectangular tank (0.45×0.45×1.1 m3). The compressed air was injected into the vertical pipe to lift the water from the reservoir. The flow map regime is established for both configurations and compared with previous studies. The two phase air-water flow structure at the expansion region is experimentally characterized. Pipeline geometry is found to have a significant influence on the output water flow rate. Using high speed photography and electrical conductivity probes, new flow regimes, such as “slug to churn” and “annular to churn” flow, are observed and their influence on the output water flow rate and efficiency are discussed. These experimental results provide fundamental insights into the physics of modified airlift pump.

scholarly journals Impacts of Water Flow Rate on Freezing Prevention of Air-Cooled Heat Exchangers in Power Plants

Energies ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 112 ◽  
Author(s):  
Yonghong Guo ◽  
Huimin Wei ◽  
Xiaoru Yang ◽  
Weijia Wang ◽  
Xiaoze Du ◽  
...  
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Power Plants ◽  
Water Flow Rate

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

Energies ◽  
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.

Optimizing the performance of hemispheric solar still using nano-ZnO with cooling the glassy cover at a variable water flow rate

2021 ◽  
Author(s):  
Mohammed El Hadi Attia ◽  
Abd Elnaby Kabeel ◽  
S. A. El-Agouz ◽  
El Mir Mabrouk Lassaad ◽  
Ravishankar Sathyamurthy ◽  
...  
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Solar Still ◽  
Nano Zno ◽  
Variable Water
Sign in / Sign up

Export Citation Format

Share Document