Lung-Diaphragm Behavior of the Respiratory System During Input From Excitation

2002 ◽  
Author(s):  
P. Ruby Mawasha ◽  
Paul Lam ◽  
Lalitha Kasturi
Keyword(s):  
Mathematical Model ◽  
Respiratory System ◽  
Periodic Motion ◽  
Constitutive Relations ◽  
Air Flow ◽  
Flow Conditions ◽  
Mouth Pressure ◽  
Parametric Studies ◽  
The Mathematical Model ◽  
Operating Regimes

A numerical behavior of a lung-diaphragm model of a respiratory system during input from mouth pressure and diaphragm excitation is being investigated. A lung-diaphragm is subject to constant inlet air-flow conditions into the respiratory system. The mouth pressure (Macia et. al., 1997) and diaphragm excitation (Ricci et. al., 2002) are described by a constitutive relations containing nonlinearities from rib cage muscles forces and inlet air-flow conditions. Within certain operating regimes, the model exhibits self-excited pulsatile periodic motion and the qualitative features of the response can be understood in terms of the underlying model. Further, the mathematical model is a more general approach and can be used to conduct parametric studies and determine the instability mechanisms involved in the modeling of lung-diaphragm behavior of the respiratory system during input from excitation.

Air Flow in Yarn Texturing Nozzles

1987 ◽  
Vol 109 (3) ◽  
pp. 197-202 ◽  
Author(s):  
M. Acar ◽  
R. K. Turton ◽  
G. R. Wray
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Experimental Work ◽  
Air Flow ◽  
Air Jet ◽  
Continuous Filament ◽  
The Mathematical Model ◽  
Experimental Nozzle ◽  
Good Agreement

The air-jet texturing process, a purely mechanical means of texturing continuous filament yarns, is described. Industrial texturing nozzles are reviewed and categorized in two groups, either as converging-diverging or cylindrical type nozzles. A mathematical model is developed for the complex airflow in cylindrical type texturing nozzles, and experimental data obtained from various nozzles verify the flow predicted by this model. The mathematical model is also shown to be in good agreement with the data obtained from a modified experimental nozzle, which has a trumpet shaped diverging exit. Further experimental work with a scaled-up model of a typical industrial texturing nozzle is also reported.

Theoretical Study on Thermal Performance of Trombe Wall Combined with Solar Air Collector

2012 ◽  
Vol 512-515 ◽  
pp. 208-213
Author(s):  
Yu Bie ◽  
Fang Zhou ◽  
Ming Fu Hu ◽  
Qian Peng ◽  
Wen Yuan Mao ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Thermal Performance ◽  
Air Flow ◽  
Flow Channel ◽  
C Programming ◽  
Solar Air Collector ◽  
Trombe Wall ◽  
Collecting Efficiency ◽  
Solar Wall ◽  
The Mathematical Model

A thermal performance mathematical model of Trombe wall combined with solar air collector was established on the base of thermodynamics and fluid dynamics analysis. Then we solved the mathematical model by means of calculating program based on C programming language. The calculating results show the influence law of the area ratio of air opening to air flow channel (Ao/Af ) and the thickness of air flow channel affected on the heat collecting efficiency of solar wall. With the increasing of Ao/Af , the efficiency increases firstly, then increases more slowly, and finally comes to steady. The thickness also affects the efficiency in the same way. Though the results still need a further validation by experiments, they are initially proved correct by the qualitative analysis. The theoretical model can be a tool for the structural optimization of the Trombe wall combined with solar air collector.

scholarly journals Study of Air Flow in A Solar Collector Equipped with Two Inclined Obstacles

2021 ◽  
Vol 321 ◽  
pp. 04015
Author(s):  
Fayssal Benosman ◽  
Mohammed Amine Amraoui
Keyword(s):  
Mathematical Model ◽  
Reynolds Number ◽  
Solar Collector ◽  
Air Flow ◽  
Solar Air Collector ◽  
The Mathematical Model ◽  
Calculation Code

In the present work we have studied the case of a conventional solar air collector and try to see how is it possible to improve it-s efficiency, by changing Reynolds number. Given the complexity of the problem we used the FLUENT calculation code. We made the mathematical model, then we gave a validation of our result by the results of Dimartini, we gave fields of speed, turbulence and a Nusselt profile and factor of friction as a function of the Reynolds Number. The results show that variation of Reynolds number has an influence on the performance of the solar collector, which is why we have used several values in order to observe the most suitable one.

scholarly journals System identification analysis for an air compressor system and enhancement proposal by sensors based in nanostructures

2019 ◽  
Vol 95 ◽  
pp. 02007
Author(s):  
Jesus A. Calderón ◽  
Cesar J. Valdivia ◽  
Roland Mas ◽  
Luis Chirinos ◽  
Enrique Barrantes ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Energy Transfer ◽  
System Identification ◽  
Mechanical System ◽  
Air Flow ◽  
Pressure Level ◽  
Air Pressure ◽  
Air Compressor ◽  
Identification Analysis ◽  
The Mathematical Model

An Air Compressor System is an equipment (mechanical system) which can transmit energy due to increase air pressure level of air flow that through it. This energy can be used in many applications, such as in drills for mining, adding air to tires on vehicles, spraying crops, etc. Therefore, it is necessary to know the mathematical model of an Air Compressor System to study all the thermodynamical variables: “Temperature, Pressure, Air Flow” which let to get a formalized explanation of the energy transfer through this equipment. Furthermore it is described that Air Compressor System can be enhanced while it uses sensors/actuators based in nanostructures.

scholarly journals Experimental calibration of the mathematical model of Air Torque Position dampers with non-cascading blades

2016 ◽  
Vol 20 (2) ◽  
pp. 567-578
Author(s):  
Sinisa Bikic ◽  
Dusan Uzelac ◽  
Masa Bukurov ◽  
Milivoj Radojcin ◽  
Ivan Pavkov
Keyword(s):  
Mathematical Model ◽  
Air Flow ◽  
Operating Conditions ◽  
Air Velocity ◽  
Experimental Calibration ◽  
Laboratory Facility ◽  
Different Types ◽  
The Moment ◽  
Air Conditioning Systems ◽  
The Mathematical Model

This paper is focused on the mathematical model of the Air Torque Position dampers. The mathematical model establishes a link between the velocity of air in front of the damper, position of the damper blade and the moment acting on the blade caused by the air flow. This research aims to experimentally verify the mathematical model for the damper type with non-cascading blades. Four different types of dampers with non-cascading blades were considered: single blade dampers, dampers with two cross-blades, dampers with two parallel blades and dampers with two blades of which one is a fixed blade in the horizontal position. The case of a damper with a straight pipeline positioned in front of and behind the damper was taken in consideration. Calibration and verification of the mathematical model was conducted experimentally. The experiment was conducted on the laboratory facility for testing dampers used for regulation of the air flow rate in heating, ventilation and air conditioning systems. The design and setup of the laboratory facility, as well as construction, adjustment and calibration of the laboratory damper are presented in this paper. The mathematical model was calibrated by using one set of data, while the verification of the mathematical model was conducted by using the second set of data. The mathematical model was successfully validated and it can be used for accurate measurement of the air velocity on dampers with non-cascading blades under different operating conditions.

scholarly journals Modelling and Simulation of Volume Controlled Mechanical Ventilation System

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yan Shi ◽  
Shuai Ren ◽  
Maolin Cai ◽  
Weiqing Xu
Keyword(s):  
Mathematical Model ◽  
Mechanical Ventilation ◽  
Respiratory System ◽  
Ventilation System ◽  
Delay System ◽  
Time Delay System ◽  
Typical Time ◽  
Controlled Mechanical Ventilation ◽  
The Mathematical Model ◽  
Volume Controlled

Volume controlled mechanical ventilation system is a typical time-delay system, which is applied to ventilate patients who cannot breathe adequately on their own. To illustrate the influences of key parameters of the ventilator on the dynamics of the ventilated respiratory system, this paper firstly derived a new mathematical model of the ventilation system; secondly, simulation and experimental results are compared to verify the mathematical model; lastly, the influences of key parameters of ventilator on the dynamics of the ventilated respiratory system are carried out. This study can be helpful in the VCV ventilation treatment and respiratory diagnostics.

Modeling and Experiment of Pulse Electrochemical Deburring on Inclined Exit Surface of Drilling Hole

2011 ◽  
Vol 328-330 ◽  
pp. 502-506 ◽  
Author(s):  
Ning Ma ◽  
Wen Ji Xu ◽  
Ze Fei Wei ◽  
Gui Bing Pang
Keyword(s):  
Mathematical Model ◽  
Influencing Factors ◽  
Applied Voltage ◽  
Voltage Pulse ◽  
Burr Height ◽  
Exit Surface ◽  
Interelectrode Gap ◽  
Parametric Studies ◽  
The Mathematical Model ◽  
Applied Voltage Pulse

In this paper the characteristics of pulse electrochemical deburring (PECD) is analyzed through a developed mathematical model and main influencing factors such as applied voltage, pulse duty factor, deburring time, initial burr height and initial interelectrode gap on burr height have been analyzed. The paper also highlights the scheme of the developed PECD system designed to operate within the parametric limits. The calculated results obtained from the mathematical model are found to be approximately consistent with the experimental results. The results show that initial burr height h0=0.057mm is removed, and the fillet radius R=0.248mm is obtained. The present paper through various parametric studies will act as a guideline for the operation of a PECD system.

Sign in / Sign up

Export Citation Format

Share Document