scholarly journals Compensation for the Effects of Ambient Conditions on the Calibration of Multi-Capillary Pressure Drop Standards

2004 ◽  
Vol 21 (3) ◽  
pp. 167-174
Author(s):  
S Colard ◽  
W Trinkies ◽  
G Cholet ◽  
B Camm ◽  
M Austin ◽  
...  
Keyword(s):  
Pressure Drop ◽  
Relative Humidity ◽  
Capillary Pressure ◽  
Atmospheric Pressure ◽  
Tobacco Industry ◽  
Simplified Model ◽  
Physical Parameters ◽  
Ambient Conditions ◽  
Capillary Tubes ◽  
Transfer Standard

AbstractCigarette draw resistance and filter pressure drop (PD) are both major physical parameters for the tobacco industry. Therefore these parameters must be measured reliably. For these measurements, specific equipment calibrated with PD transfer standards is used. Each transfer standard must have a known and stable PD value, such standards usually being composed of several capillary tubes associated in parallel. However, PD values are modified by ambient conditions during calibration of such standards, i.e. by temperature and relative humidity (RH) of air, and atmospheric pressure. In order to reduce the influence of these ambient factors, a simplified model was developed for compensating the effects of ambient conditions on the calibration of multi-capillary PD standards.

Research on Pressure Drop Transfer Standard Based on CFD

2012 ◽  
Vol 542-543 ◽  
pp. 1105-1108
Author(s):  
Zhi Cai Jiang ◽  
Xue Ding ◽  
Hang Zhao ◽  
Zhong Di Su
Keyword(s):  
Mathematical Model ◽  
Pressure Drop ◽  
Laminar Flow ◽  
Air Flow ◽  
Differential Pressure ◽  
Capillary Tubes ◽  
Measuring Systems ◽  
Transfer Standard ◽  
Flow Part ◽  
Cfd Method

The pressure drop transfer standard is a major measurement element in the pressure drop measurement device as a traceability element. This paper analyzed the air flow in the capillary tubes, and mathematical model of pressure drop transfer standard was got by the differential pressure at inlet non-laminar flow part and differential pressure in the laminar flow part. A CFD method adopting laminar model is used to confirm the theory. The pressure drop value was calculated by the diameters and length of all capillary tubes measured by OGP video measuring systems, and the result shows the calculated value was verified by the calibration value.

scholarly journals Effects of ambient conditions on multi-capillary ventilation rate

2016 ◽  
Vol 20 (3) ◽  
pp. 855-857
Author(s):  
Qing Zhang ◽  
Rong-Chao Yang ◽  
Qian Miao ◽  
Shu-Xing Wu ◽  
Kai Zhang
Keyword(s):  
Pressure Drop ◽  
Numerical Investigation ◽  
Physical Parameter ◽  
Tobacco Industry ◽  
Ventilation Rate ◽  
Ambient Conditions ◽  
Additional Pressure ◽  
Non Linear ◽  
Low Sensitivity

As a major physical parameter for the tobacco industry, the ventilation rate of cigarette should be measured reliably. Theoretical and numerical investigation on ef-fects of ambient conditions (e. g., cumulative flux of ozone and additional pressure drop) on the ventilation rate was carried out. It was found that the standards exhibited a non-linear airflow component, which explains why additional pressure drop has an effect on the calibrated value, and had low sensitivity to cumulative flux of ozone.

scholarly journals The effects of ambient conditions on the calibration of air flow plate standards

2013 ◽  
Vol 17 (5) ◽  
pp. 1517-1520
Author(s):  
Qian Miao ◽  
Rong-Chao Yang ◽  
Qing Zhang ◽  
Jing Cheng ◽  
Jia-Cun Shao ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
Volume Flow Rate ◽  
Air Flow ◽  
Volume Flow ◽  
Calibration Data ◽  
Ambient Conditions ◽  
Numerical Examples ◽  
The Relationship

The volume flow rate measured by air flow plate is influenced by the ambient conditions during the calibration. A series of numerical examples are conducted for the relationship and the outcomes demonstrated that the calibration is quite sensitive to the atmospheric pressure and the ambient temperature, but insensitive to relative humidity. The experiment model has been applied to calibration results with wide ranging ambient conditions. In conclusion, the results of this study demonstrate the benefits to calibration data of minimizing the effects of ambient conditions.

Fluorescence of BODIPY Dyes in Gas Phase at near Ambient Conditions

2020 ◽  
Author(s):  
Kseniya A. Mariewskaya ◽  
Denis Larkin ◽  
Yuri Samoilichenko ◽  
Vladimir Korshun ◽  
Alex Ustinov
Keyword(s):  
Gas Phase ◽  
Molecular Interactions ◽  
Atmospheric Pressure ◽  
Fluorescence Spectra ◽  
Visible Range ◽  
Intrinsic Properties ◽  
Ambient Conditions ◽  
Ideal Model ◽  
Molecular Fluorescence ◽  
Tesla Coil

Molecular fluorescence is a phenomenon that is usually observed in condensed phase. It is strongly affected by molecular interactions. The study of fluorescence spectra in the gas phase can provide a nearly-ideal model for the evaluation of intrinsic properties of the fluorophores. Unfortunately, most conventional fluorophores are not volatile enough to allow study of their fluorescence in the gas phase. Here we report very bright gas phase fluorescence of simple BODIPY dyes that can be readily observed at atmospheric pressure using conventional fluorescence instrumentation. To our knowledge, this is the first example of visible range gas phase fluorescence at near ambient conditions. Evaporation of the dye in vacuum allowed us to demonstrate organic molecular electroluminescence in gas discharge excited by electric field produced by a Tesla coil.

Study of fluid flow through a channel deformed by piezoelement

2018 ◽  
Vol 13 (3) ◽  
pp. 1-10 ◽  
Author(s):  
I.Sh. Nasibullayev ◽  
E.Sh Nasibullaeva ◽  
O.V. Darintsev
Keyword(s):  
Fluid Flow ◽  
Pressure Drop ◽  
Boundary Conditions ◽  
Flow Rate ◽  
Contact Surface ◽  
Piezoelectric Element ◽  
Neumann Boundary ◽  
Differential Pressure ◽  
Physical Parameters ◽  
Flow Through

The flow of a liquid through a tube deformed by a piezoelectric cell under a harmonic law is studied in this paper. Linear deformations are compared for the Dirichlet and Neumann boundary conditions on the contact surface of the tube and piezoelectric element. The flow of fluid through a deformed channel for two flow regimes is investigated: in a tube with one closed end due to deformation of the tube; for a tube with two open ends due to deformation of the tube and the differential pressure applied to the channel. The flow rate of the liquid is calculated as a function of the frequency of the deformations, the pressure drop and the physical parameters of the liquid.

High-performance inverted planar perovskite solar cells without a hole transport layer via a solution process under ambient conditions

2015 ◽  
Vol 3 (38) ◽  
pp. 19294-19298 ◽  
Author(s):  
Xichang Bao ◽  
Qianqian Zhu ◽  
Meng Qiu ◽  
Ailing Yang ◽  
Yujin Wang ◽  
...  
Keyword(s):  
Relative Humidity ◽  
High Performance ◽  
Perovskite Solar Cells ◽  
Solution Process ◽  
Hole Transport ◽  
Transport Layer ◽  
Hole Transport Layer ◽  
Ambient Conditions ◽  
High Quality ◽  
Ito Glass

High-quality CH3NH3PbI3 perovskite films were directly prepared on simple treated ITO glass in air under a relative humidity of lower than 30%.

scholarly journals A Simplified Model for Predicting Friction Factors of Laminar Blood Flow in Small-Caliber Vessels

Fluids ◽  
2018 ◽  
Vol 3 (4) ◽  
pp. 75 ◽  
Author(s):  
Aikaterini Mouza ◽  
Olga Skordia ◽  
Ioannis Tzouganatos ◽  
Spiros Paras
Keyword(s):  
Blood Flow ◽  
Pressure Drop ◽  
Friction Factor ◽  
Small Diameter ◽  
Numerical Data ◽  
Blood Flow Rate ◽  
Vessel Diameter ◽  
Simplified Model ◽  
Glycerol Solution ◽  
Fanning Friction Factor

The aim of this study was to provide scientists with a straightforward correlation that can be applied to the prediction of the Fanning friction factor and consequently the pressure drop that arises during blood flow in small-caliber vessels. Due to the small diameter of the conduit, the Reynolds numbers are low and thus the flow is laminar. This study has been conducted using Computational Fluid Dynamics (CFD) simulations validated with relevant experimental data, acquired using an appropriate experimental setup. The experiments relate to the pressure drop measurement during the flow of a blood analogue that follows the Casson model, i.e., an aqueous Glycerol solution that contains a small amount of Xanthan gum and exhibits similar behavior to blood, in a smooth, stainless steel microtube (L = 50 mm and D = 400 μm). The interpretation of the resulting numerical data led to the proposal of a simplified model that incorporates the effect of the blood flow rate, the hematocrit value (35–55%) and the vessel diameter (300–1800 μm) and predicts, with better than ±10% accuracy, the Fanning friction factor and consequently the pressure drop during laminar blood flow in healthy small-caliber vessels.

Ambient Condition Effects on NOx and CO Emissions From Process Heaters

2008 ◽  
Author(s):  
Wesley R. Bussman ◽  
Charles E. Baukal
Keyword(s):  
Atmospheric Pressure ◽  
Ambient Air ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Ambient Conditions ◽  
Fuel Gas ◽  
Natural Draft ◽  
Actual Operating ◽  
Wide Range ◽  
Pollution Emissions

Because process heaters are typically located outside, their operation is subject to the weather. Heaters are typically tuned at a given set of conditions; however, the actual operating conditions may vary dramatically from season to season and sometimes even within a given day. Wind, ambient air temperature, ambient air humidity, and atmospheric pressure can all significantly impact the O2 level, which impacts both the thermal efficiency and the pollution emissions from a process heater. Unfortunately, most natural draft process burners are manually controlled on an infrequent basis. This paper shows how changing ambient conditions can considerably impact both CO and NOx emissions if proper adjustments are not made as the ambient conditions change. Data will be presented for a wide range of operating conditions to show how much the CO and NOx emissions can be affected by changes in the ambient conditions for fuel gas fired natural draft process heaters, which are the most common type used in the hydrocarbon and petrochemical industries. Some type of automated burner control, which is virtually non-existent today in this application, is recommended to adjust for the variations in ambient conditions.

scholarly journals AVALIAÇÃO DE PRODUTOS OBTIDOS PELA DESIDRATAÇÃO OSMÓTICA DE BANANA SEGUIDA DE SECAGEM

2003 ◽  
Vol 21 (1) ◽  
Author(s):  
PAULO HENRIQUE MACHADO DE SOUSAPAULO HEN MACHADO DE SOUSA ◽  
GERALDO ARRAES MAIA ◽  
MEN DE SÁ MOREIRA DE SOUZA FILHO ◽  
RAIMUNDO WILANE DE FIGUEIREDO ◽  
RENATA TIEKO NASSU ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Atmospheric Pressure ◽  
Room Temperature ◽  
Storage Stability ◽  
Osmotic Dehydration ◽  
Storage Period ◽  
Sensory Characteristics ◽  
Sensorial Analysis ◽  
Physico Chemical ◽  
Microbiological Stability

Foram obtidos dois produtos de banana por desidratação osmótica, um sob pressão atmosférica e outro sob vácuo, com complemento de secagem em estufa. A estabilidade dos produtos foi estudada, durante 120 dias, mediante análises físico-químicas, microbiológicas e sensoriais. Nesse período, os produtos ficaram armazenados em temperatura ambiente (23,4-34,1oC) e umidade relativa entre 33-81%. Concluiu-se que os produtos mantiveram suas características químicas, físico-químicas e sensoriais, além de estabilidade microbiológica (pouca variação durante o período de armazenamento). Somente a cor dos produtos apresentou variação expressiva. Sugere-se o tratamento utilizando osmose com vácuo seguido de secagem para produção de banana passa. EVALUATION OF PRODUCTS OBTAINED BY THE BANANA’S OSMOTIC DEHYDRATION FOLLOWED OF DRYING Abstract It was obtained two bananas products through osmotic dehydration, one under atmospheric pressure and other under vacuum, with drying complement in stove. The storage stability of these products was studied, during 120 days, through physicalchemical, microbiological and sensorial analysis. In this period, the products were stored at room temperature (23,4-34,1oC) and relative humidity between 33-81%. It was concluded that the obtained products maintained their chemical, physico-chemical and sensory characteristics, beyond microbiological stability (small variations during the storage period). Only the color of the produtcs presented more expressive variations. Therefore it is suggested the treatment using osmosis with vacuum followed by oven drying for the production of banana fig.

Sign in / Sign up

Export Citation Format

Share Document