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An experimental methodology for investigating the effects of anti-icing fluids is presented in this paper. A wing model was designed, fabricated, and instrumented for testing anti-icing fluids in a wind tunnel facility. In addition, a video capturing method was developed and used to document fluid behavior during simulated takeoff tests. The experiments were performed at the Wichita State University 2.13-m by 3.05-m (7-ft by 10-ft) wind tunnel facility with two pseudoplastic fluids representative of Type IV anti-icing fluids. The experimental data obtained included fluid wave propagation speeds, chordwise fluid thickness distributions as a function of time, and boundary layer velocity profiles for the clean and fluid contaminated wing model at select chordwise stations. During simulated takeoffs with initial fluid depths of either 4 mm or 2 mm, the fluids were observed to thin in the forward (upstream) regions of the wing model and accumulate in the aft regions.

Cold flow properties have historically been important for diesel and jet fuels. Reflecting the importance of cold flow properties, several standards have been developed to characterize pour point, cloud point, and filterability. An emphasis on characterizing fuels based on standard testing methods has led to large amounts of data that describe how fuels perform but very little published data that describe what is happening at the molecular level and to the composition of fuels. Motivated by a desire to have an improved understanding of the cold flow behavior of Fischer-Tropsch fuels, an experimental method was developed to provide easy acquisition of data on the changing compositions of liquid and solid phases as Fischer-Tropsch and diesel fuels traverse cloud point, pour point, and additive-enhanced pour point temperatures.

The present scenario of increasing the production rates in drilling demands high speed drilling while at the same time maintaining the quality of the drilled holes. Of the many factors that affect the high-speed drilling process, such as speed, feed rate, material of drill and work piece, and drill geometry this study attempts only to study the effect of drill geometry in high-speed drilling of aluminum sheet metal. In the Experiments conducted, different speeds, feed rates and drill bits of varying geometry are utilized in order to study their effects on hole quality as it relates to hole diameter and burr formation. Also the variation of thrust and torque with increase in speed over a speed range of 6,000 to 30,000 rpm has been studied.

Separated flows and subsequent formation of shear layers are important fluid processes which play a dominant role in numerous engineering applications. Prediction of this fluid process is an important element in the design and analysis of highspeed vehicles and, ultimately, in the performance and trajectory analysis. The prediction methodology used in the current study includes the numerical solution of the Navier-Stokes equations on a multi-block grid system. Several turbulence models are used to investigate their performance for compressible, turbulent, separated and shear layer flows. The computational results are compared to available experimental data.

The effect of Gurney flaps on three-dimensional wings was investigated in the 7x10 feet low speed wind tunnel. There have been a number of studies on Gurney flaps in recent years. However, these studies have been limited to two-dimensional airfoils. A comprehensive investigation on the effect of Gurney flaps for a wide range of configurations and test conditions was conducted at Wichita State University. In this part of the investigation, straight and tapered three-dimensional wings with Natural Laminar Flow (NLF) airfoil sections were tested. Gurney flaps spanning 4.5, 3.0, and 1.5 feet were tested on a straight NLF wing of 5 feet span. Compared to the clean wing, the 4.5 feet span 0.017c and 0.033c height Gurney flaps increased the maximum lift coefficient by 17% and 22%, respectively. The increase in maximum lift coefficient was proportionately smaller with the shorter span Gurney flaps.

A series of aerodynamically driven model mounts for dynamic wind tunnel testing were designed, built and evaluated at Wichita State University. The mount proved to be very responsive, stable and capable of generating a wide variety of pitching motions. However, the response of an early variant of this mechanism displayed “stair-step” like behavior during slow pitching motions and damped oscillations at the end of rapid pitching motions. Numerical and experimental evaluations demonstrated that these undesired characteristics are minimized when the size of the control surface is increased and the inertia of the apparatus is reduced. In addition, this novel mechanism was utilized to demonstrate the type of valuable data that can be obtained. Force data for an oscillating NACA 0012 wing section is provided.

The effect of Gurney flaps on a NACA 0011 airfoil was investigated. Gurney flaps provide a substantial increase in lift while the penalty in drag is small. With the Gurney flap, the airfoil pressure distribution shows increased suction on the upper surface and higher pressure on the lower surface compared to the clean airfoil. This change in pressure is most profound on the lower surface just in front of the Gurney flap. Since separation occurs on the upper surface upon stall, this higher pressure condition on the lower surface continues into the post-stall regime. Thus, the NACA 0011 airfoil with Gurney flaps generates lift coefficients greater than one even under post-stall conditions.

An investigation was performed to evaluate a novel and inexpensive wind tunnel model mount for dynamic aerodynamic testing. A computer analysis code was developed to identify the dimensions of the control surface needed to produce a desired pitching motion for a delta wing. The code was then used to design and build a dynamic model apparatus that was evaluated in a low speed wind tunnel at Wichita State University. The dynamic model mount and control were evaluated for a variety of motions, including constant pitch rate ramps, constant frequency oscillations and impulse or step inputs. Results from the ramp and oscillation test indicated the system is very responsive and capable of a wide range of motion.

A wind tunnel balance was designed to measure the aerodynamic loads on a ruddevator system during tests in the WSU 7′ x 10′ wind tunnel. The design goal for the system was to produce a balance that could accurately uncouple the components of the aerodynamic loads such that the lift, pitching moment and rolling moment relative to the balance reference point could be measured separately. This was a challenge because of the dimensional constraints and because of the accuracy requirement for a large range of possible load distributions during the tests. A simple flat plate idealization of the actual balance system was designed for laboratory structural tests to investigate some possible balance design strategies prior to the construction of the actual balance. Specific parameters of interests during these tests were that of choice of material, level of response of the structure to simulated service loads and strain gage selection and circuit design.

The flow about multi-element airfoil configurations is investigated using the unsteady Reynolds averaged Navier-Stokes equations. An explicit scheme is used to advance the solution in time while a finite difference scheme is applied to discretize the flux terms. An algebraic and two one-equation turbulence models are used to model turbulence. The domain about each multi-element airfoil is discretized with structured Chimera grids. The multi-element configurations presented in this paper include two airfoils with slotted flaps and an airfoil with a 50% chord vented aileron deflected at 90 degrees. Subsonic flow computations are performed for attached and separated flow conditions. The computational results obtained with the CRTVD code developed at Wichita State University are in good correlation with wind tunnel data and with computational results obtained with the INS2D computer code developed at NASA Ames research center.

The motivation for this project was to design, and develop an aircraft seat to meet the proposed FAA 32g vertical/longitudinal dynamic test requirements specified in NPRM 93-71. A major goal of the design was to develop a production-quality seat in terms of weight, comfort, appearance, simplicity, and manufacturability. The relevant injury criteria was to obtain an occupant lumbar (spinal) load below 6670 N (1500 1bf). The design incorporated energy absorbing devices in the cushion and chair legs. The seat developed was based on the Beech King Air design and incorporated a modified seat frame, seat back, and reclining mechanism. The seat cushions were provided by Oregon Aero, while the seat pan and seat legs were designed and manufactured at WSU.

A new class of aerodynamic control devices have recently been designed specifically for wind turbine applications. These new controls were tested to evaluate their effectiveness in modulating wind turbine power output and for slowing or stopping a wind turbine in high wind or loss of generator situations. While these control devices were developed specifically for wind turbine applications, there exists the possibility that alternate aviation uses exist. In particular, these trailing-edge control devices were evaluated for reducing aircraft landing distances, generating rapid rates of descent, deep stall or spin recovery and for high angle of attack control.

The architecture and training of artificial neural networks are briefly described. Five applications of these networks to design and analysis problems are presented; three in aerodynamics and two in flight dynamics. The aerodynamics cases are those of a harmonically oscillating airfoil, a pitching delta wing, and airfoil design. The flight dynamic examples involve control of a super maneuver and a decoupled control case. It is demonstrated that highly nonlinear aerodynamic cases can be generalized with sufficient accuracy for design purposes. It is shown that although neural networks generalize well on the aerodynamic problems, they appear lacking comparable robustness in modeling dynamic systems. It is also shown that generalization appears to become weak outside of the training domain.

The aerodynamic properties of a forward-swept wing were tested at low Reynolds numbers. The investigation was performed in a low-speed wind tunnel using a reflection plane model. Tunnel balance, model pressure taps, and flow visualization results were utilized to characterize the wing behavior over a range of Reynolds numbers from 0.25 × 106 - 0.75 × 106. In addition, the experimental data is compared to results obtained using a recently developed computer program known as WING3D. This modified Non-Planar Vortex Lattice Method program can calculate total wing lift and surface pressure distributions. The forward-swept wing has good aerodynamic qualities; in addition, the flow, on the outboard sections of the wing, remains attached beyond stall. The comparison of WING3D and experimental surface pressure distributions is good.