scholarly journals Kinematics motion of paddy in hot air pulse flow

2020 ◽  
Vol 187 ◽  
pp. 04011
Author(s):  
Nuttapong Wongbubpa ◽  
Krawee Treeamnuk ◽  
Tawarat Treeamnuk
Keyword(s):  
Reynolds Number ◽  
Travel Time ◽  
Motion Analysis ◽  
Tube Length ◽  
Pulse Flow ◽  
Total Distance ◽  
Hot Air ◽  
Actual Movement

This research aims to study the characteristic of paddy motion under the hot air pulse flow in the drying tube length 2 m by using the kinematics motion analysis. The equations of paddy motion are analyzed to evaluate the pattern of paddy motion, total distance that the paddy can travel through the drying tube and Reynolds number of paddy. Results found that Model I, II and III consume the paddy travel time of approximately 1.3, 5.0 and 2.2 s and give a total distance of 2.6, 2.7 and 2.5 m and they have maximum travel velocity of 4.12, 1.37 and 1.85 m/s respectively. When considering the Reynolds number, the models I, II and III give the most values from similar calculations with 1,837, 1,816 and 1,821 respectively. Based on various parameters from all of models, Model III was the closest characteristic of paddy motion to the actual movement in the system.

Detection of P-S travel time for low SNR event by particle motion analysis

2021 ◽  
Author(s):  
Jingyi Sun ◽  
Yusuke Mukuhira ◽  
Takayuki Nagata ◽  
Taku Nonomura ◽  
Hirokazu Moriya ◽  
...  
Keyword(s):  
Travel Time ◽  
Motion Analysis ◽  
Particle Motion ◽  
Low Snr

scholarly journals A New Approach to the Analysis of Pitch-Positions in Professional Soccer

2019 ◽  
Vol 66 (1) ◽  
pp. 143-153 ◽  
Author(s):  
Marek Konefał ◽  
Paweł Chmura ◽  
Tomasz Zając ◽  
Jan Chmura ◽  
Edward Kowalczuk ◽  
...  
Keyword(s):  
Motion Analysis ◽  
Soccer Players ◽  
Motion Analysis System ◽  
Running Speed ◽  
Heat Maps ◽  
New Approach ◽  
Total Distance ◽  
Professional Soccer ◽  
Percentage Share ◽  
Analysis System

Abstract The purpose of the study was to examine how various playing positions affected the number of (and percentage breakdowns for) physical and technical activities of soccer players in the Germany’s Bundesliga. A further objective was to identify and present features distinguishing between the activities of players within the Defender, Midfielder and Forward formations. The study sample comprised 4426 individual match observations of 473 soccer players competing in the Bundesliga during the 2016/2017 domestic season. Data from the Impire AG motion analysis system, and the so-called ”heat maps” it supplies, revealed areas in which players spent most time during a match, with 22 different playing positions on the pitch identified in consequence. Players in the formation comprising Defenders did not differ significantly in relation to the number of accelerations, the number of shots or the percentage of duels won. Furthermore, there were no significant differences among Midfielders in regard to total distance covered, mean running speed, the number of accelerations, the number of duels and the percentage of duels won. Likewise, Forwards did not differ in distances covered at ≥24 km/h, average running speed, the number of sprints, the number of shots, the proportion of on-target passes, the number of duels, or the percentage share of duels won. Irrespective of the formation or position on the pitch, today’s game of soccer also pays great importance to the number of accelerations, as well as the number of duels engaged in, and their effectiveness.

Overland-flow travel time versus Reynolds number a comment

1977 ◽  
Vol 35 (1-2) ◽  
pp. 203-204
Author(s):  
Mohammad Akram Gill
Keyword(s):  
Reynolds Number ◽  
Travel Time ◽  
Overland Flow

Experimental Study of Droplet Evaporation in a High-Temperature Air Stream

1983 ◽  
Vol 105 (2) ◽  
pp. 384-388 ◽  
Author(s):  
M. Renksizbulut ◽  
M. C. Yuen
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Liquid Droplets ◽  
Transfer Number ◽  
Number Range ◽  
Transfer Rates ◽  
Hot Air ◽  
Air Stream ◽  
Stream Density ◽  
Freely Suspended

Heat transfer rates to simulated and freely suspended liquid droplets were measured in an atmospheric hot air tunnel. The experiments were limited to water, methanol, and heptane droplets in a Reynolds number range of 25 to 2000, and a mass transfer number range of 0.07 to 2.79. The present experimental data together with data by others can best be correlated by Nuf(1+Bf).7 = 2 + 0.57 ReM1/2 Prf1/3, where properties are evaluated at film conditions except for the density in the Reynolds number which is the free-stream density. Thus the data shows that at higher temperatures, evaporation reduces heat transfer rates directly by a factor of (1 + Bf).7. Indirectly, evaporation affects heat transfer rates through the changes in both the composition and temperature of the surrounding gaseous medium.

Fuzzy Ramp Metering: Design Overview and Simulation Results

1998 ◽  
Vol 1634 (1) ◽  
pp. 10-18 ◽  
Author(s):  
Cynthia Taylor ◽  
Deirdere Meldrum ◽  
Les Jacobson
Keyword(s):  
Fuzzy Logic ◽  
Travel Time ◽  
Fuzzy Controller ◽  
Simulation Software ◽  
Ramp Metering ◽  
Traffic Conditions ◽  
Total Distance ◽  
Total Travel Time ◽  
Vehicle Delay ◽  
Simulation Results

A fuzzy logic ramp-metering algorithm was designed to overcome the limitations of conventional ramp-metering strategies. The fuzzy controller demonstrated improved robustness, prevented heavy congestion, intelligently balanced conflicting needs, and tuned easily. The objective was to maximize total distance traveled and minimize total travel time and vehicle delay, while maintaining acceptable ramp queues. A multiple-ramp study site from the Seattle I-5 corridor was modeled and tested using the freeway simulation software, FRESIM. For five of the six testing sets, encompassing a variety of traffic conditions, the fuzzy controller outperformed the three other controllers tested.

scholarly journals The Heat Exchanger Performance of Shell and Multi Tube Helical Coil as a Heater through the Utilization of a Diesel Machine’s Exhaust Gas

2016 ◽  
Vol 5 (1) ◽  
Author(s):  
. Zainuddin ◽  
Jufrizal Nurdin ◽  
Eswanto Is
Keyword(s):  
Heat Exchanger ◽  
Performance Testing ◽  
Tube Length ◽  
Helical Coil ◽  
Exhaust Gas ◽  
Air Heater ◽  
Hot Air ◽  
Drying Up ◽  
Helical Coils ◽  
Gas Potential

A review on reutilization of heat waste from a diesel machine is absolutely important. This is because the exhaust gas potential of a Diesel machine keeps increasing and not much has been utilized by the industry. One of the techniques of reutilizing the heat waste in industry is by using a heat exchanger. The technique is also very useful for the environment because it can reduce air pollution caused by the exhaust gas of the diesel machine. The main purpose of the research is to find out the capability of shell and multi-tube helical coil HE as an air heater by utilizing the exhaust gas of the Diesel machine. The heat exchanger of shell and multi-tube helical coil  utilizes the exhaust thermal gas of the Diesel machine as the air heater already made. The apparatus has the following dimension: the shell length of 1.05 m, diameter 0.1524 m, tube length of 3.25 m with 20 coils, tube diameter of 0.011 m, coil diameter of 0.0508 m with 4 helical coils. The type of Diesel machine to use in the testing is 4FB1 Isuzu Diesel engine. The machine has the maximum machine power and rotation of 54 kW and 3,600 rpm. The performance testing of heat exchanger has been conducted in some variations of Diesel machine rotations of 1,500 rpm, 1,750 rpm, 2,000 rpm, 2,250 rpm and 2,500 rpm. The testing result shows a maximum effectiveness to happen at the machine rotation of 1,500 rpm. The maximum effectiveness to get is 67.8% and then it goes down drastically in accordance with the increase of air mass flow rate. The hot air temperature created is from 47.1°C to 52.3°C so that it can be used for the purpose of drying up the unhulled rice.

Effect of standoff distance and area ratio on the performance of circular exhaust ejector using computational fluid dynamics

2017 ◽  
Vol 232 (15) ◽  
pp. 2821-2832 ◽  
Author(s):  
L Singh ◽  
SN Singh ◽  
SS Sinha
Keyword(s):  
Fluid Dynamics ◽  
Reynolds Number ◽  
Cross Section ◽  
Circular Cross Section ◽  
Area Ratio ◽  
Standoff Distance ◽  
Tube Length ◽  
Mass Entrainment ◽  
Section Shape ◽  
Ejector Nozzle

Numerical investigation is carried out to study the effect of standoff distance and area ratio on mass entrainment of an air–air circular exhaust ejector. Nozzle and mixing tube are the two components of an ejector, and for the present study, circular cross section shape has been chosen. Numerical simulations have been carried out at Reynolds number in the range of 6.85 × 104 and 4.11 × 105. Area ratio is varied between 1.25 < area ratio < 4 and standoff distance is varied from 1 Dnz < standoff distance < 4 Dnz, where Dnz represent the nozzle exit diameter. It is observed that for the ejector configuration with area ratio as 2, 2.25, and 2.5, the mass entrainment characteristics are nearly independent of standoff distance between 1 Dnz to 4 Dnz. For ejector configuration with area ratio below 2, mass entrainment decreases with increase in standoff distance. For ejector configuration with area ratio greater than 2.5, mass entrainment increases with increase in standoff distance for the range investigated and has the tendency to taper off beyond 4 Dnz for most of the area ratios. Effect of change in mixing tube length is also studied. It is seen that the mass entrainment improves with increase in length up to 8 Dnz. Further increase in length does not effect mass entrainment. This study provides important guidelines that can aid in arriving at an optimal design of circular exhaust ejectors.

The impact of an additional inlet point on the hot outlet side on the vortex tube productivity

2019 ◽  
Vol 14 (3) ◽  
pp. 176-183
Author(s):  
L.Yu. Privalov ◽  
C.I. Mikhaylenko
Keyword(s):  
Vortex Tube ◽  
Computation Time ◽  
Ideal Gas ◽  
Effective Length ◽  
Tube Length ◽  
Inlet Channel ◽  
Air Inlet ◽  
Hot Air ◽  
Speed Up ◽  
The Impact

Based on numerical simulation, the production of cold and hot air on a modified countercurrent vortex tube is studied. A feature of the modification under study is an additional air inlet area along the axis of the pipe from the hot outlet side. An additional point of blowing air is designed to redistribute the gas flows at the cold and hot outlets. Computational experiments were performed in the OpenFOAM software package using the sonicFoam solver based on the k−ε turbulence model under the assumption of an ideal gas. The dependence of the flow rate and temperature at the cold and hot outlets for different lengths of the main channel of the vortex tube was studied. For all considered pipe lengths, finite-volume grids were prepared in which the rectangular shape of the cells was preferably observed and their excessive stretching was avoided. To speed up the simulations, MPI technology was used; spatial decomposition of the original mesh was performed by decomposePar utility into equal parts along the pipe. This approach allowed us to reduce the computation time by approximately 3.5 times when running on six processes. The results of parallel modeling were combined with the reconstructPar utility and further processed by a Python program written using the vtk library. Thus, average values of the main physical characteristics by time and space at the cold and hot outlets were obtained. Results are discussed that demonstrate the effect of the vortex tube length on temperature and air flow at the respective outputs. The behavior of its main characteristics, non-standard for a vortex tube, is shown, an assumption is made about the reason for this behavior: the collision of very fast flows makes instability. Preliminary conclusions are made about choosing the effective length of the vortex tube with an additional air inlet channel at which the ratio of air temperature at the hot and cold outlets is the largest.

The Problem of Pneumatic Pressure Lag: Part 1—Steady-State Flow in a Tubing System

1964 ◽  
Vol 86 (2) ◽  
pp. 234-240 ◽  
Author(s):  
A. L. Ducoffe ◽  
F. M. White
Keyword(s):  
Reynolds Number ◽  
Steady State ◽  
Room Temperature ◽  
Diameter Ratio ◽  
Tube Length ◽  
Series System ◽  
Steady State Flow ◽  
Flow Equations ◽  
Constant Diameter ◽  
System Geometry

An analytical and experimental investigation of the steady-state isothermal flow in a series system, comprised of a constant-diameter tube with reduced size unions located at the tube extremities, is reported herein. The pressure drop across the system has been determined experimentally as a function of the system geometry. The parameters chosen for investigation were the tube length to diameter ratio L/D, the union diameter to tube diameter ratio Df/D, and the Reynolds number. The ranges of the parameters investigated consisted of 159 ≤ L/D ≤ 1475, 0.7 ≤ Df/D ≤ 1.0, and 200 ≤ Reynolds number ≤ 100,000. All tests were conducted at room temperature. The theory is derived considering each geometric element of the system, such as inlet, development length, exit, and so on, and a set of five simultaneous algebraic flow equations results. Solutions to these were obtained by use of a digital computer. A pseudo-friction factor, for fully developed laminar or turbulent flow, is defined. The result indicates that the correlation of theory with experiment is quantitative over the range of parameters investigated.

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