Airflow pattern induced by ceiling fan under different rotation speeds and blowing directions

2019 ◽  
Vol 29 (10) ◽  
pp. 1425-1440 ◽  
Author(s):  
Huan Wang ◽  
Maohui Luo ◽  
Guijin Wang ◽  
Xianting Li
Keyword(s):  
New Technology ◽  
Three Dimensional ◽  
Air Conditioning System ◽  
Airflow Pattern ◽  
Room Size ◽  
Colour Sequence ◽  
Air Mixing ◽  
Particle Streak Velocimetry ◽  
Air Speed ◽  
Velocity Turbulence

Ceiling fans have been widely used as effective cooling and air mixing method for building environment conditioning. Understanding its airflow characteristics can be helpful to utilize ceiling fan or integrate it with background air conditioning system. However, the airflow induced by ceiling fan has different flow patterns under different rotating speeds and blowing directions. To date, it is still challenging to capture those complicated airflow fields in room scale. In this study, the airflow pattern induced by a ceiling fan was measured with a new technology, quad-view colour sequence particle streak velocimetry. A series of isothermal experiments were conducted under five rotation speed levels with downward and upward blowing directions in a room-size (4 m × 2.5 m × 3 m) chamber. Based on comprehensive three-dimensional three-component vector measurement results, the average velocity, turbulence intensity and vorticity on the middle section were calculated and used to analyse airflow patterns induced by ceiling fan. The results show that the blowing direction of the fan determines the indoor airflow pattern. When blowing downward, the flow will cause high diversion between jet core under the fan blades and surrounding region. While for upward blowing, the air speed in lower part of the room is much lower but pretty uniform. The detailed measured airflow fields can serve as reference for ceiling fan design and operation.

scholarly journals Measurement of airflow pattern induced by ceiling fan with quad-view colour sequence particle streak velocimetry

2019 ◽  
Vol 152 ◽  
pp. 122-134 ◽  
Author(s):  
Huan Wang ◽  
Hong Zhang ◽  
Xiaowei Hu ◽  
Maohui Luo ◽  
Guijin Wang ◽  
...  
Keyword(s):  
Airflow Pattern ◽  
Colour Sequence ◽  
Particle Streak Velocimetry

Implementation of demand-oriented ventilation with adjustable fan network

2020 ◽  
Vol 29 (4) ◽  
pp. 621-635 ◽  
Author(s):  
Huan Wang ◽  
Guijin Wang ◽  
Xianting Li
Keyword(s):  
Indoor Environment ◽  
Ventilation System ◽  
Test Chamber ◽  
Hvac Systems ◽  
The Novel ◽  
Airflow Pattern ◽  
Colour Sequence ◽  
Axial Fans ◽  
Particle Streak Velocimetry ◽  
Occupied Zone

Airflow patterns are essential for heating, ventilation and air conditioning (HVAC) systems. Traditional HVAC systems are predesigned and operated using a fixed airflow pattern. However, the indoor occupancy and heat source always vary and therefore, the fixed flow pattern cannot efficiently maintain the required indoor environment conditions. In this study, a novel Adjustable Fan Network (AFN) for improving airflow pattern manoeuvrability is proposed. It integrates multiple small and adjustable axial fans into an AFN, enabling it to change the airflow pattern based on the actual demand with only one set of equipment. Further, the outflow characteristics of two types of axial fans were measured using a quad-view colour sequence particle streak velocimetry (CSPSV) in a test chamber. The ventilation system was then designed based on typical scenarios. Finally, the performance of the AFN was evaluated under different scenarios using a quad-view CSPSV. Based on the results, it was evident that the AFN can provide a better direct supply of air to the occupied zone under different scenarios. With the growing demand for personal thermal comfort and energy-saving in HVAC systems, the novel AFN system has a great potential to be a highly controllable terminal for demand-oriented ventilation.

Numerical Simulation and Optimization of Air Distribution in Large Space

2014 ◽  
Vol 1070-1072 ◽  
pp. 2021-2026
Author(s):  
Ze Hang Du ◽  
Chun Hua Liu ◽  
Guang Zhou
Keyword(s):  
Numerical Simulation ◽  
Three Dimensional ◽  
Flow Distribution ◽  
Large Space ◽  
Air Conditioning System ◽  
Simulation And Optimization ◽  
Air Inlet ◽  
Air Supply ◽  
Dimensional Distribution ◽  
Air Speed

In recent years, people pay increasing attention to the issue whether indoor air conditioning system can meet the requirements of thermal comfort under the circumstance of good air quality and reduce energy consumption. FLUENT, commercial computational fluid dynamics software is used to simulate the three-dimensional distribution of temperature and velocity in the subject hotel atrium. The turbulence model modified by buoyancy was used to solve equations. The SIMPLE scheme was used for numerical discrimination. Distribution of temperature, velocity on some typical section and the atrium space can be obtained; the result of numerical simulation can be visualized by post-processing module of FLUENT and TECPLOT software. The influence to the air flow distribution is simulated and calculated by the elements of different rates, angle, and height of the air supply flow. As for the specified case of the project, an optimized solution is obtained, that is supply air speed 6 m/s, angle 15°, air inlet height 7.5m, air temperature 291K.

Clinical Value of Computer-Assisted Taylor Three-dimensional External Fixation in the Treatment of Tibiofibular Fracture (Preprint)

2020 ◽  
Author(s):  
Hongfeng Sheng ◽  
Weixing Xu ◽  
Bin Xu ◽  
Hongpu Song ◽  
Di Lu ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Internal Fixation ◽  
External Fixation ◽  
External Fixator ◽  
Theoretical Basis ◽  
New Technology ◽  
Three Dimensional ◽  
Computer Assisted ◽  
Clinical Value

UNSTRUCTURED The retrospective study of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures provides a theoretical basis for the application of this technology. The paper collected 28 patients with tibiofibular fractures from the Department of Orthopaedics in our hospital from March 2015 to June 2018. After the treatment, the follow-up evaluation of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures and concurrency the incidence of the disease, as well as the efficacy and occurrence of the internal fixation of the treatment of tibial fractures in our hospital. The results showed that Taylor's three-dimensional external fixator was superior to orthopaedics in the treatment of tibiofibular fractures in terms of efficacy and complications. To this end, the thesis research can be concluded as follows: Taylor three-dimensional external fixation in the treatment of tibiofibular fractures is more effective, and the incidence of occurrence is low, is a new technology for the treatment of tibiofibular fractures, it is worthy of clinical promotion.

scholarly journals 3D Reconstruction of Cultural Heritage Sites as an Educational Approach. The Sanctuary of Delphi

2021 ◽  
Vol 11 (8) ◽  
pp. 3635
Author(s):  
Ioannis Liritzis ◽  
Pantelis Volonakis ◽  
Spyros Vosinakis
Keyword(s):  
University Students ◽  
3D Reconstruction ◽  
Cultural Heritage ◽  
New Technology ◽  
Three Dimensional ◽  
Computer Gaming ◽  
Educational Approach ◽  
Heritage Sites ◽  
3D Environment ◽  
Almost All

In the field of cultural heritage, three-dimensional (3D) reconstruction of monuments is a usual activity for many professionals. The aim in this paper focuses on the new technology educational application combining science, history, and archaeology. Being involved in almost all stages of implementation steps and assessing the level of participation, university students use tools of computer gaming platform and participate in ways of planning the virtual environment which improves their education through e-Learning. The virtual 3D environment is made with different imaging methods (helium-filled balloon, Structure for motion, 3D repository models) and a developmental plan has been designed for use in many future applications. Digital tools were used with 3D reconstructed buildings from the museum archive to Unity 3D for the design. The pilot study of Information Technology work has been employed to introduce cultural heritage and archaeology to university syllabuses. It included students with a questionnaire which has been evaluated accordingly. As a result, the university students were inspired to immerse themselves into the virtual lab, aiming to increasing the level of interaction. The results show a satisfactory learning outcome by an easy to use and real 3D environment, a step forward to fill in needs of contemporary online sustainable learning demands.

scholarly journals Room Size Influences Flow in Robotic-Assisted Surgery

2021 ◽  
Vol 18 (15) ◽  
pp. 7984
Author(s):  
Falisha Kanji ◽  
Tara Cohen ◽  
Myrtede Alfred ◽  
Ashley Caron ◽  
Samuel Lawton ◽  
...  
Keyword(s):  
New Technology ◽  
Surgical Robots ◽  
Physical Size ◽  
Robotic Assisted ◽  
Surgical Technology ◽  
Room Size ◽  
Robotic Assisted Surgery ◽  
Academic Hospitals ◽  
Environmental Causes ◽  
The Impact

The introduction of surgical technology into existing operating rooms (ORs) can place novel demands on staff and infrastructure. Despite the substantial physical size of the devices in robotic-assisted surgery (RAS), the workspace implications are rarely considered. This study aimed to explore the impact of OR size on the environmental causes of surgical flow disruptions (FDs) occurring during RAS. Fifty-six RAS procedures were observed at two academic hospitals between July 2019 and January 2021 across general, urologic, and gynecologic surgical specialties. A multiple regression analysis demonstrated significant effects of room size in the pre-docking phase (t = 2.170, df = 54, β = 0.017, p = 0.035) where the rate of FDs increased as room size increased, and docking phase (t = −2.488, df = 54, β = −0.017, p = 0.016) where the rate of FDs increased as room size decreased. Significant effects of site (pre-docking phase: p = 0.000 and docking phase: p = 0.000) were also demonstrated. Findings from this study demonstrate hitherto unrecognized spatial challenges involved with introducing surgical robots into the operating domain. While new technology may provide benefits towards patient safety, it is important to consider the needs of the technology prior to integration.

scholarly journals 3DP Printing of Oral Solid Formulations: A Systematic Review

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 358 ◽  
Author(s):  
Chiara R. M. Brambilla ◽  
Ogochukwu Lilian Okafor-Muo ◽  
Hany Hassanin ◽  
Amr ElShaer
Keyword(s):  
Systematic Review ◽  
Data Extraction ◽  
New Technology ◽  
Three Dimensional ◽  
Extraction Process ◽  
Carcinogenic Risk ◽  
Drug Dissolution ◽  
Dissolution Profile ◽  
Disintegration Time ◽  
Advantages And Disadvantages

Three-dimensional (3D) printing is a recent technology, which gives the possibility to manufacture personalised dosage forms and it has a broad range of applications. One of the most developed, it is the manufacture of oral solid dosage and the four 3DP techniques which have been more used for their manufacture are FDM, inkjet 3DP, SLA and SLS. This systematic review is carried out to statistically analyze the current 3DP techniques employed in manufacturing oral solid formulations and assess the recent trends of this new technology. The work has been organised into four steps, (1) screening of the articles, definition of the inclusion and exclusion criteria and classification of the articles in the two main groups (included/excluded); (2) quantification and characterisation of the included articles; (3) evaluation of the validity of data and data extraction process; (4) data analysis, discussion, and conclusion to define which technique offers the best properties to be applied in the manufacture of oral solid formulations. It has been observed that with SLS 3DP technique, all the characterisation tests required by the BP (drug content, drug dissolution profile, hardness, friability, disintegration time and uniformity of weight) have been performed in the majority of articles, except for the friability test. However, it is not possible to define which of the four 3DP techniques is the most suitable for the manufacture of oral solid formulations, because the selection is affected by different parameters, such as the type of formulation, the physical-mechanical properties to achieve. Moreover, each technique has its specific advantages and disadvantages, such as for FDM the biggest challenge is the degradation of the drug, due to high printing temperature process or for SLA is the toxicity of the carcinogenic risk of the photopolymerising material.

Preoperative Use of CT Angiography in Infants With Coarctation of the Aorta

2017 ◽  
Vol 8 (2) ◽  
pp. 196-202 ◽  
Author(s):  
Kirsten Rose-Felker ◽  
Joshua D. Robinson ◽  
Carl L. Backer ◽  
Cynthia K. Rigsby ◽  
Osama M. Eltayeb ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Surgical Approach ◽  
New Technology ◽  
Three Dimensional ◽  
Coarctation Of The Aorta ◽  
Computed Tomographic Angiography ◽  
Great Vessel ◽  
Z Score ◽  
Computed Tomographic ◽  
Tomographic Angiography

Background: Computed tomographic angiography (CTA) and echocardiography (echo) are used preoperatively in coarctation of the aorta to define arch hypoplasia and great vessel branching. We sought to determine differences in quantitative measurements, as well as surgical utility, between modalities. Methods: Infants (less than six months) with both CTA and echo prior to coarctation repair from 2004 to 2013 were included. Measurements were compared and correlated with surgical approach. Three surgeons reviewed de-identified images to predict approach and characterize utility. Computed tomographic angiography radiation dose was calculated. Results: Thirty-three patients were included. No differences existed in arch measurements between echo and CTA ( z-score: −2.59 vs −2.43; P = .47). No differences between modalities were seen for thoracotomy ( z-score: −2.48 [echo] vs −2.31 [CTA]; P = .48) or sternotomy ( z-score: −3.13 [echo] vs −3.08 [CTA]; P = .84). Computed tomographic angiography delineated great vessel branching pattern in two patients with equivocal echo findings ( P = .60). Surgeons rated CTA as far more useful than echo in understanding arch hypoplasia and great vessel branching in cases where CTA was done to resolve anatomical questions that remain after echo evaluation. Two of three surgeons were more likely to choose the surgical approach taken based on CTA (surgeon A, P = .02; surgeon B, P = .01). Radiation dose averaged 2.5 (1.6) mSv and trended down from 2.9 mSv (1.8 mSv; n = 20) to 1.6 mSv (0.5 mSv; n = 7) ( P = .06) with new technology. Conclusion: Although CTA and echo measurements of the aorta do not differ, CTA better delineates branching and surgeons strongly prefer it for three-dimensional arch anatomy. We recommend CTA for patients with anomalous arch branching patterns, diffuse or complex hypoplasia, or unusual arch morphology not fully elucidated by echo.

Novel application of three-dimensional HDlive imaging in prenatal diagnosis from the first trimester

2015 ◽  
Vol 43 (2) ◽  
Author(s):  
Ritsuko Kimata Pooh ◽  
Asim Kurjak
Keyword(s):  
Human Development ◽  
New Technology ◽  
Three Dimensional ◽  
First Trimester ◽  
High Definition ◽  
Noninvasive Diagnostics ◽  
Anatomy And Physiology ◽  
Early Human Development ◽  
2D Ultrasound ◽  
Early Human

AbstractRecent development of three-dimensional (3D) high definition (HD) ultrasound has resulted in remarkable progress in visualization of early embryos and fetuses in sonoembryology. The new technology of HDlive assesses both structural and functional developments in the first trimester with greater reliably than two-dimensional (2D) ultrasound. The ability to visualize not only fetal face, hands, fingers, feet, and toes, but also amniotic membranes, is better with volumetric ultrasound than 2D ultrasound. In this article, detailed and comprehensive structures of normal and abnormal fetuses depicted by 3D HDlive are presented, including various faces of Down’s syndrome and holoprosencephaly, as well as low-set ear and finger/toe abnormalities from the first trimester. Three-dimensional HDlive further “humanizes” the fetus, enables detailed observation of the fetal face in the first trimester as shown in this article, and reveals that a small fetus is not more a fetus but a “person” from the first trimester. There has been an immense acceleration in understanding of early human development. The anatomy and physiology of embryonic development is a field where medicine exerts greatest impact on early pregnancy at present, and it opens fascinating aspects of embryonic differentiation. Clinical assessment of those stages of growth relies heavily on 3D/four-dimensional (4D) HDlive, one of the most promising forms of noninvasive diagnostics and embryological phenomena, once matters for textbooks are now routinely recorded with outstanding clarity. New advances deserve the adjective “breathtaking”, including 4D parallel study of the structural and functional early human development.

A New Technology for Three-Dimensional Cell Culture: The Hydrodynamic Focusing Bioreactor

1999 ◽  
Author(s):  
Yow-Min D. Tsao ◽  
Steve R. Gonda
Keyword(s):  
Cell Culture ◽  
New Technology ◽  
Three Dimensional ◽  
Culture Vessel ◽  
Air Bubbles ◽  
Hydrodynamic Focusing ◽  
Shaped Cell ◽  
Fluid Environment ◽  
Dimensional Cell ◽  
Low Shear

Abstract The Hydrodynamic Focusing Bioreactor (HDFB) developed by NASA at the Johnson Space Center provides a unique hydrofocusing capability that simultaneously enables a low-shear culture environment and a unique hydrofocusing-based “herding” of suspended cells, cell aggregates, and air bubbles. The HDFB is a rotating dome-shaped cell culture vessel with a centrally located sampling port and an internal rotating viscous spinner attached to a rotating base. The vessel and viscous spinner can rotate at different speeds and in either the same or different directions. Adjusting the differential rotation rate between the vessel and spinner results in a controllable hydrodynamic focusing force. The resultant hydrodynamic force suspends the cells in a low-shear fluid environment that supports the formation of delicate three-dimensional tissue assemblies. Both suspension and anchorage-dependent cells have been successfully cultured.

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