The collection of aerosol droplets by resting tsetse flies, Glossina morsitans Westwood (Diptera: Glossinidae)

1989 ◽  
Vol 79 (4) ◽  
pp. 613-623 ◽  
Author(s):  
D. R. Johnstone ◽  
J. F. Cooper ◽  
H. M. Dobson ◽  
C. R. Turner
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Collection Efficiency ◽  
Natural Habitat ◽  
Control Measures ◽  
Tsetse Flies ◽  
Glossina Morsitans ◽  
Speed Range ◽  
Low Speed Wind Tunnel ◽  
Very High

AbstractInsecticidal aerosols dispersed from aircraft are used in control measures against Glossina spp., and the interpretation of spray monitoring data in terms of the likely effect on the flies requires some knowledge of variation of the collection efficiency of the flies under a range of appropriate conditions. A low speed wind tunnel was used to measure the collection efficiencies of the various component parts of an adult of G. morsitans Westwood when at rest on cylinders simulating the branches and twigs of the natural habitat. The wind speed range was from 0·25 to 1·5 m/s and monodisperse droplets 10, 15, 20 and 25 μm in diameter were used. Although certain body zones exhibited very high apparent collection efficiencies (primarily due to interception), the average overall efficiencies varied from as low as 0·8% for 10-μm droplets at 0·25 m/s up to 22% for 25-μm droplets at 1·5 m/s.

Turbulent plumes of heat, moist heat, and carbon dioxide elicit upwind anemotaxis in tsetse flies Glossina morsitans morsitans Westwood (Diptera: Glossinidae)

2002 ◽  
Vol 80 (7) ◽  
pp. 1149-1155 ◽  
Author(s):  
W G Evans ◽  
R H Gooding
Keyword(s):  
Carbon Dioxide ◽  
Wind Tunnel ◽  
Relative Humidity ◽  
Glossina Morsitans Morsitans ◽  
Tsetse Flies ◽  
Glossina Morsitans ◽  
Low Velocity ◽  
Upwind Flight ◽  
Moist Heat ◽  
Heated Air

The roles and interactions of turbulent plumes of heat, moist heat, and carbon dioxide in mediating upwind flight of adult tsetse flies (Glossina morsitans morsitans Westwood) were investigated using a wind tunnel in a constant-environment chamber. Heat fluctuations in the plume that were detected by a thermocouple and displayed as oscilloscope traces allowed direct visualization of the structures of the plumes. Significantly more flies flew upwind when exposed to plumes of (i) carbon dioxide (0.0051% above background) and air (58% relative humidity) compared with air alone; (ii) carbon dioxide and heated air (35% relative humidity and temperature fluctuating up to 0.09°C above background) compared with carbon dioxide and air; and (iii) carbon dioxide and moist (82% relative humidity) heated air (temperature fluctuating up to 0.05°C above background) compared with carbon dioxide and heated air. However, there were no significant differences in upwind flight of flies exposed to plumes of (i) air compared with humidified air (65% relative humidity); (ii) carbon dioxide and heated air compared with heated air alone; and (iii) carbon dioxide and moist heated air compared with moist heated air alone. Recorded temperature fluctuations in heat plumes transported downwind from a tethered steer in a pasture showed patterns similar to those produced in the wind-tunnel plumes. These results suggest that host emissions of carbon dioxide alone and combined heat and moisture carried downwind by low-velocity winds elicit upwind anemotaxis in tsetse flies, which distinguish these emissions from a background of lower atmospheric levels.

Gliding Flight of the Dog-Faced Bat Rousettus Aegyptiacus Observed in a Wind Tunnel

1971 ◽  
Vol 55 (3) ◽  
pp. 833-845 ◽  
Author(s):  
C. J. PENNYCUICK
Keyword(s):  
Wind Tunnel ◽  
Lift Coefficient ◽  
Trailing Edge ◽  
Number Range ◽  
High Speeds ◽  
Gliding Flight ◽  
Speed Range ◽  
Simple Regression Analysis ◽  
Drag Analysis ◽  
Very High

1. A bat was trained to fly in a tilting wind tunnel. Stereoscopic photographs were taken, both by reflected and by transmitted light, and measurements of best gliding angle were made. 2. Variation of wing span and area at different speeds was much less than in birds. This is attributed to the construction of the wing, which prevents the bat from folding back the manus in flight, because this would lead to collapse of the plagiopatagium. 3. The trailing edge of the wing is normally deflected upwards in flight, at least in the distal parts. This is interpreted as providing longitudinal stability. The plagiopatagialis proprii muscles appear to act as an elevator, by deflecting the trailing edge of the plagiopatagium upwards. 4. The speed range over which the bat could glide was 5·3-11·0 m/s. Its maximum lift coefficient was 1·5, and its best glide ratio 6·8:1. The Reynolds number range, based on mean chord, was 3·26 x 104 to 6·79 x 104. 5. A simple regression analysis of the glide polar indicated a very high span efficiency factor (k) and low wing profile drag coefficient (Cdp). On the other hand, a drag analysis on the assumption that k = 1 leads to an improbably large increase in the estimated Cdp at low speeds. It is suggested that the correct interpretation probably lies between these extremes, with k ≊ 1·5; Cdp would then be about 0·02 at high speeds, rising to somewhat over 0·1 at the minimum speed. 6. It would appear that the bat is not so good as a pigeon at fast gliding, but better at low-speed manoeuvring. On most points of performance, however, the two are remarkably similar.

scholarly journals Effects of central stabilizing barriers on flutter performances of a suspension bridge with a truss-stiffened deck under skew winds

2018 ◽  
Vol 22 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Ledong Zhu ◽  
Xiao Tan ◽  
Zhenshan Guo ◽  
Quanshun Ding
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Inclination Angle ◽  
Suspension Bridge ◽  
Control Measures ◽  
Wind Effect ◽  
Wind Condition ◽  
Wind Tunnel Tests ◽  
Critical Wind Speed ◽  
Bridge Span

To improve the flutter performance of a suspension bridge with a 1088-m-span truss-stiffened deck, the aerodynamic measures of upper and lower central stabilizing barriers were investigated at first via wind tunnel tests of sectional model under the normal wind condition. The yaw wind effect on the flutter performance of the bridge with the above aerodynamic measures was then examined via a series of wind tunnel tests of oblique sectional models. The test results show that the effect of the lower central stabilizing barrier on the flutter critical wind speed is remarkably different from that of the upper central stabilizing barrier for both the normal and skew wind cases. The inclination angle +3° is the most unfavorable inclination angle to the flutter performance of the truss-stiffened suspension bridge no matter whether the aerodynamic control measures are adopted or not. Furthermore, for most cases, the lowest flutter critical wind speed occurs when the incident wind deviates from the normal direction of the bridge span by a small yaw angle between 5° and 10°.

The distribution of the tsetse flies Glossina morsitans submorsitans and G. palpalis gambiensis (Diptera: Glossinidae) in The Gambia and the application of survey results to tsetse and trypanosomiasis control

1993 ◽  
Vol 83 (4) ◽  
pp. 625-632 ◽  
Author(s):  
P. Rawlings ◽  
M.L. Ceesay ◽  
T.J. Wacher ◽  
W.F. Snow
Keyword(s):  
Environmental Factors ◽  
The Gambia ◽  
Control Measures ◽  
Evergreen Forest ◽  
General Distribution ◽  
Tsetse Flies ◽  
Glossina Morsitans ◽  
Glossina Morsitans Submorsitans ◽  
Survey Results ◽  
Riparian Habitats

AbstractA country-wide survey of the distribution of tsetse flies Glossina morsitans submorsitans Newstead and G. palpalis gambiensis Vanderplank was carried out in The Gambia, during 1989–1990, using box traps at 1654 sites over an area of 10,000 km2 The general distribution of tsetse had changed little during the last 45 years. G. m. submorsitans was present in dry, canopied woodland throughout most of the country, but was absent from an area south of the River Gambia stretching from the coast to some 100 km inland. G. p. gambiensis occurred in evergreen forest and woodland near the coast, and in riparian habitats along the length of the River Gambia and its major tributaries. Nowhere in the country was more than 20 km from tsetse-infested areas. Five major foci of G. m. submorsitans infestation were identified. Demographic, climatic and environmental factors affect tsetse populations in The Gambia, but it is expected that these foci of infestation will persist for at least the next 5–10 years. The numbers of tsetse trapped, expressed as relative densities, were used to assess the extent and severity of losses from trypanosomiasis to different categories of livestock. Survey results such as these could be used to assess whether control measures to reduce tsetse challenge are likely to be economically viable by using techniques such as insecticide-impregnated targets, pour-ons or chemotherapy.

scholarly journals Analisis Flutter Pada Uji Model Separuh Sayap Pesawat N219 di Terowongan Angin Kecepatan Rendah

WARTA ARDHIA ◽  
2017 ◽  
Vol 42 (4) ◽  
pp. 165
Author(s):  
Sayuti Syamsuar ◽  
Muhamad Kusni ◽  
Adityo Suksmono ◽  
Muhamad Ivan Aji Saputro
Keyword(s):  
Wind Tunnel ◽  
Computational Analysis ◽  
Aerodynamic Force ◽  
Unstable Condition ◽  
Low Speed ◽  
Wing Flutter ◽  
Flutter Speed ◽  
Wing Model ◽  
Speed Range ◽  
Low Speed Wind Tunnel

Fenomena flutter akan terjadi apabila ada gaya dan momen aerodinamika yang berinteraksi berlebihan di permukaan sayap di dalam terowongan angin atau pesawat sesungguhnya. Sayap akan bergetar dan berosilasi bertambah besar menuju ke keadaan tidak stabil. Osilasi osilasi membuat osilasi yang lebih besar terjadi sehingga frekuensi dan damping pada daerah kecepatan tertentu dengan mudah terlihat apabila terjadi flutter pada model separuh sayap. Penelitian ini, digunakan model separuh sayap dari pesawat N219 yang di uji pada terowongan angin kecepatan rendah BBTA3, kawasan Puspiptek, Serpong. Kecepatan flutter terjadi pada 40,5 m/s pada hasil analisis komputasional dan hasil pengujian di terowongan angin sebesar 40,83 m/s. [The Analysis of Half Wing Flutter Test N219 Aircraft Model in The Low Speed Wind Tunnel] The flutter phenomenon will occur when the aerodynamic force and moment excessively interacted on the wing surface, whether it takes place in the wind tunnel or on the real aircraft. The wing will vibrate and oscillate towards an unstable condition. Each oscillation will subsequently build a greater one until the damping and frequency on a certain speed range can be seen easily when flutter occur on the half wing model. On this research, the half wing model of N219 aircraft was tested in the low speed wind tunnel of BBTA3, Puspitek Serpong. The flutter speed occurred at 40,5 m/s based on computational analysis while the wind tunnel result is at the speed of 40,83 m/s.

Survival and behaviour of tsetse flies (Diptera, Glossinidae) released in the field: a comparison between wild flies and animal-fed and in vitro-fed laboratory-reared flies

1976 ◽  
Vol 66 (4) ◽  
pp. 731-744 ◽  
Author(s):  
G. A. Vale ◽  
J. W. Hargrove ◽  
A. M. Jordan ◽  
P. A. Langley ◽  
A. R. Mews
Keyword(s):  
Body Size ◽  
Natural Habitat ◽  
Release Site ◽  
Glossina Morsitans Morsitans ◽  
Tsetse Flies ◽  
Glossina Morsitans ◽  
Male And Female ◽  
Wing Damage ◽  
Blood Meals

AbstractMale and female Glossina morsitans morsitans Westw. which emerged from puparia produced by animal-fed and in vitro-fed colonies in England were marked distinctively with non-toxic paint and released into a natural habitat of G. morsitans and G. pallidipes Aust. in Rhodesia. Concurrently, adults of both species which emerged from locally-collected puparia were marked and released. Recaptures from artificial refuges, odour attractants and mobile baits at periods up to 59 days after release and at distances up to 1800 m from the release site indicated no clear differences between native G. morsitans and the two laboratory-reared groups in respect of body size, amount of fat present at emergence, survival, dispersal, availability to a range of baits, diet, speed of taking a first meal, wing damage and insemination rate. Although the blood-meal identifications for marked female G. morsitans were similar to those for both sexes of unmarked flies, blood-meals from marked males showed a relatively high proportion of bovid identifications. Unmarked flies caught were generally older than marked catches. The ratio of females to males in unmarked samples (1:1 for G. morsitans, 2:1 for G. pallidipes) was roughly double that in marked catches.

Spray Drift from Dicamba and Glyphosate Applications in a Wind Tunnel

2017 ◽  
Vol 31 (3) ◽  
pp. 387-395 ◽  
Author(s):  
Guilherme Sousa Alves ◽  
Greg R. Kruger ◽  
João Paulo A. R. da Cunha ◽  
Bruno C. Vieira ◽  
Ryan S. Henry ◽  
...  
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Laser Diffraction ◽  
Spray Drift ◽  
Downwind Distance ◽  
Fluorescent Tracer ◽  
Drift Potential ◽  
Herbicide Treatments ◽  
Low Speed Wind Tunnel ◽  
Nozzle Type

With the recent introductions of glyphosate- and dicamba-tolerant crops, such as soybean and cotton, there will be an increase in POST-applied tank-mixtures of these two herbicides. However, few studies have been conducted to evaluate drift from dicamba applications. This study aimed to evaluate the effects of dicamba with and without glyphosate sprayed through standard and air induction flat-fan nozzles on droplet spectrum and drift potential in a low-speed wind tunnel. Two standard (XR and TT) and two air induction (AIXR and TTI) 110015 nozzles were used. The applications were made at 276 kPa pressure in a 2.2 ms−1 wind speed. Herbicide treatments evaluated included dicamba alone at 560 gaeha−1 and dicamba+glyphosate at 560+1,260 gaeha−1. The droplet spectrum was measured using a laser diffraction system. Artificial targets were used as drift collectors, positioned in a wind tunnel from 2 to 12 m downwind from the nozzle. Drift potential was determined using a fluorescent tracer added to solutions, quantified by fluorimetry. Dicamba droplet spectrum and drift depended on the association between herbicide solution and nozzle type. Dicamba alone produced coarser droplets than dicamba+glyphosate when sprayed through air induction nozzles. Drift decreased exponentially as downwind distance increased and it was reduced using air induction nozzles for both herbicide solutions.

Corrigendum - Factors affecting uredospore production and dispersal in Tranzschelia discolor

1970 ◽  
Vol 21 (6) ◽  
pp. 905
Author(s):  
MV Carter ◽  
WJ Moller ◽  
SM Pady
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Fold Increase ◽  
Heavy Rain ◽  
Growing Season ◽  
Control Measures ◽  
Dormant Period ◽  
Factors Affecting ◽  
Wind Speeds ◽  
Tranzschelia Discolor

Uredosori of Tranzschelia discolor mature on infected twigs of susceptible peach varieties in July and uredospores are produced at a diminishing rate throughout most of the following growing season. Dry liberation of uredospores from sori on leaves occurs at a rate which increases logarithmically with the wind speed. The onset of heavy rain, or irrigation from overhead sprinklers, may cause a temporary 10-fold increase in the concentration of airborne uredospores within an orchard. In wind tunnel tests, bombardment of sori by water droplets caused liberation of uredospores at wind speeds below those normally required to release detectable quantities. The results emphasize the importance of directing control measures at prevention of the overwintering phases of the rust, which in peaches occur on twigs, and in almonds on rusted leaves retained throughout the short dormant period.

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