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You searched for subject:(Pilot mathematical model). Showing records 1 – 3 of 3 total matches.

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University of Melbourne

1. Cho, Youngsoo. Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane.

Degree: 2013, University of Melbourne

Gold mine tailings water has been considered for recycling so that fresh water consumption can be reduced. However, the tailings water contains, along with a small amount of free cyanide, a high concentration of thiocyanate that can decrease the efficiency of the flotation of the sulfide minerals containing gold. Therefore, the possibility of using polymer inclusion membranes has been explored to remove thiocyanate and cyanide from tailings water. A polymer inclusion membrane containing 70% (m/m) poly(vinyl chloride) (PVC), 20% (m/m) Aliquat 336 and 10% (m/m) 1-tetradecanol was selected after a number of membrane screening experiments and found to successfully extract thiocyanate from a solution with pH in the range of 7-10 and the extracted thiocyanate in the membrane was efficiently back-extracted using 1 M NaNO3 solution. A mathematical model of thiocyanate extraction was developed and provided excellent agreement with the experimental data, thus allowing both the membrane extraction constant (18.9) and the diffusion coefficient (2.4x10-13 m2 s-1) of thiocyanate within the membrane to be successfully determined. The transport of thiocyanate from the feed to the receiving solution was investigated by varying the membrane thickness (46.1, 78.6, 108.5, 125.7 um) and the temperature (25, 35, 45, 65 °C) and the rate was found to increase with decrease the membrane thickness and with increase in the temperature. A laboratory scale pilot system has been designed to provide a large surface area (61.5 cm2) of flat sheet membrane in contact with both the feed (1000 mg L-1 SCN-) and receiving (1 M NaNO3) solutions. Thiocyanate was completely transported for over 135 days using a slow flow rate (0.028 mL min-1) and excellent stability of the flat sheet PIM used in the system was observed. The receiving solution was recirculated in the system to limit the consumption of the receiving solution and the removal of thiocyanate from the receiving solution was essential to maintain high transport efficiency. This was achieved by the approach of precipitation of thiocyanate as CuSCN. A study of cyanide extraction and oxidation in the membrane was also carried out to explore the possibility of using PIMs for cyanide clean-up of tailings water.

Subjects/Keywords: polymer inclusion membrane; thiocyanate extraction and transport; mathematical model; laboratory scale pilot system; thiocyanate precipitation; cyanide extraction and oxidation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Cho, Y. (2013). Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/38248

Chicago Manual of Style (16th Edition):

Cho, Youngsoo. “Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane.” 2013. Doctoral Dissertation, University of Melbourne. Accessed January 25, 2021. http://hdl.handle.net/11343/38248.

MLA Handbook (7th Edition):

Cho, Youngsoo. “Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane.” 2013. Web. 25 Jan 2021.

Vancouver:

Cho Y. Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane. [Internet] [Doctoral dissertation]. University of Melbourne; 2013. [cited 2021 Jan 25]. Available from: http://hdl.handle.net/11343/38248.

Council of Science Editors:

Cho Y. Removal of thiocyanate and cyanide from gold mine tailings water using a polymer inclusion membrane. [Doctoral Dissertation]. University of Melbourne; 2013. Available from: http://hdl.handle.net/11343/38248


University of Pretoria

2. [No author]. Longitudinal handling characteristics of a tailless gull-wing aircraft .

Degree: 2008, University of Pretoria

A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in the sweep and dihedral angle. An example of this type of aircraft is the Exulans. This aircraft is currently under development at the University of Pretoria. The handling quality study was focussed on pitch axis dynamics. The Exulans is a research testbed that will be used to investigate the swept gull-wing configuration and its special controls by means of full-scale flight testing. Variable wing sweep, twisting elevons and winglets will be investigated as means of control. These control devices are configured in such a way as to have minimum impact on the performance of the aircraft. The handling qualities of the swept gull-wing configuration have to be acceptable while using these different control strategies. The study was launched to investigate whether a gull-wing configuration aircraft will have satisfactory handling qualities at CG positions associated with the most favourable aerodynamic performance. There is an aerodynamic performance gain in designing an aircraft so that the CG falls on the so-called `E-point'. The E-point is the centre of pressure for an elliptical circulation distribution. An elliptical circulation distribution is associated with the highest Oswald efficiency for an aircraft. Time domain simulation techniques and frequency domain analysis techniques were used to analyse the handling qualities of the gull-wing configuration. The C-star criterion was used to analyse handling qualities with time domain simulation data as input. Comparative time domain simulations were performed between the Exulans and other aircraft to compare handling qualities. Eigenvalue analysis was used together with the thumbprint criterion to investigate inherent gull-wing airframe dynamics. The Shomber-Gertsen and Military Specification 8785 criteria were also used for the same purpose. The Neal-Smith method was used to investigate the effect of control authority on handling qualities and the effect of a pilot. The Monnich and Dalldorff criterion was used to evaluate gust handling qualities. An analysis chart by Fremaux and Vairo was used to evaluate the tumbling susceptibility of the gull-wing configuration. The pitch handling quality investigation shows sufficient promise that the swept gull-wing configuration will have acceptable handling qualities with the CG placed at positions associated with optimised aerodynamic performance. Analysis showed that the swept gull-wing configuration is potentially prone to tumbling. With low static margins, the configuration should exhibit improved handling qualities in gusty conditions when compared to existing tailless aircraft. It is recommended that a lateral handling quality study be performed before full scale flight testing commences on the Exulans. In addition, the possibility of wingtip stall must be investigated for the case of the swept gull-wing configuration. Advisors/Committee Members: Theron, Nicolaas J (advisor).

Subjects/Keywords: Flight simulation; Tumbling; Thumbprint criterion; Neal-smith analysis; C-star criterion; Shomber-gertsen analysis; Pilot induced oscillation; Oswald efficiency; Pilot mathematical model; Variable sweep wing; Exulans; Variable static margin; Swept gull-wing configuration; O-point; E-point; Handling qualities; Gust handling qualities; Tailless aircraft; Pecking; Monnich and dalldorff criterion; UCTD

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

author], [. (2008). Longitudinal handling characteristics of a tailless gull-wing aircraft . (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-09182008-132941/

Chicago Manual of Style (16th Edition):

author], [No. “Longitudinal handling characteristics of a tailless gull-wing aircraft .” 2008. Masters Thesis, University of Pretoria. Accessed January 25, 2021. http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.

MLA Handbook (7th Edition):

author], [No. “Longitudinal handling characteristics of a tailless gull-wing aircraft .” 2008. Web. 25 Jan 2021.

Vancouver:

author] [. Longitudinal handling characteristics of a tailless gull-wing aircraft . [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 25]. Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.

Council of Science Editors:

author] [. Longitudinal handling characteristics of a tailless gull-wing aircraft . [Masters Thesis]. University of Pretoria; 2008. Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/


University of Pretoria

3. Agenbag, Daniel Sarel. Longitudinal handling characteristics of a tailless gull-wing aircraft.

Degree: Mechanical and Aeronautical Engineering, 2008, University of Pretoria

A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in the sweep and dihedral angle. An example of this type of aircraft is the Exulans. This aircraft is currently under development at the University of Pretoria. The handling quality study was focussed on pitch axis dynamics. The Exulans is a research testbed that will be used to investigate the swept gull-wing configuration and its special controls by means of full-scale flight testing. Variable wing sweep, twisting elevons and winglets will be investigated as means of control. These control devices are configured in such a way as to have minimum impact on the performance of the aircraft. The handling qualities of the swept gull-wing configuration have to be acceptable while using these different control strategies. The study was launched to investigate whether a gull-wing configuration aircraft will have satisfactory handling qualities at CG positions associated with the most favourable aerodynamic performance. There is an aerodynamic performance gain in designing an aircraft so that the CG falls on the so-called `E-point'. The E-point is the centre of pressure for an elliptical circulation distribution. An elliptical circulation distribution is associated with the highest Oswald efficiency for an aircraft. Time domain simulation techniques and frequency domain analysis techniques were used to analyse the handling qualities of the gull-wing configuration. The C-star criterion was used to analyse handling qualities with time domain simulation data as input. Comparative time domain simulations were performed between the Exulans and other aircraft to compare handling qualities. Eigenvalue analysis was used together with the thumbprint criterion to investigate inherent gull-wing airframe dynamics. The Shomber-Gertsen and Military Specification 8785 criteria were also used for the same purpose. The Neal-Smith method was used to investigate the effect of control authority on handling qualities and the effect of a pilot. The Monnich and Dalldorff criterion was used to evaluate gust handling qualities. An analysis chart by Fremaux and Vairo was used to evaluate the tumbling susceptibility of the gull-wing configuration. The pitch handling quality investigation shows sufficient promise that the swept gull-wing configuration will have acceptable handling qualities with the CG placed at positions associated with optimised aerodynamic performance. Analysis showed that the swept gull-wing configuration is potentially prone to tumbling. With low static margins, the configuration should exhibit improved handling qualities in gusty conditions when compared to existing tailless aircraft. It is recommended that a lateral handling quality study be performed before full scale flight testing commences on the Exulans. In addition, the possibility of wingtip stall must be investigated for the case of the swept gull-wing configuration. Advisors/Committee Members: Theron, Nicolaas J. (advisor).

Subjects/Keywords: Flight simulation; Tumbling; Thumbprint criterion; Neal-smith analysis; C-star criterion; Shomber-gertsen analysis; Pilot induced oscillation; Oswald efficiency; Pilot mathematical model; Variable sweep wing; Exulans; Variable static margin; Swept gull-wing configuration; O-point; E-point; Handling qualities; Gust handling qualities; Tailless aircraft; Pecking; Monnich and dalldorff criterion; UCTD

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Agenbag, D. (2008). Longitudinal handling characteristics of a tailless gull-wing aircraft. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/28011

Chicago Manual of Style (16th Edition):

Agenbag, Daniel. “Longitudinal handling characteristics of a tailless gull-wing aircraft.” 2008. Masters Thesis, University of Pretoria. Accessed January 25, 2021. http://hdl.handle.net/2263/28011.

MLA Handbook (7th Edition):

Agenbag, Daniel. “Longitudinal handling characteristics of a tailless gull-wing aircraft.” 2008. Web. 25 Jan 2021.

Vancouver:

Agenbag D. Longitudinal handling characteristics of a tailless gull-wing aircraft. [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 25]. Available from: http://hdl.handle.net/2263/28011.

Council of Science Editors:

Agenbag D. Longitudinal handling characteristics of a tailless gull-wing aircraft. [Masters Thesis]. University of Pretoria; 2008. Available from: http://hdl.handle.net/2263/28011

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