Mechanical vibrations are usually found as an unwanted side effect in many areas of engineering. Examples include vehicle vibrations on uneven roads or engine vibrations. Vibration theory is a particularly challenging area in the field of mechanics.
Learning Objectives And Experiments:
1. Damped and undamped resonance
2. Absorber effect in multi-mass oscillators
3. Experiments with pendulums
Reduced pendulum length
Spring-mass system
Katers pendulum
4. Bar-type oscillator
Forced vibration
Undamped oscillation
Damped oscillation
Features:
Detailed, wide-ranging series of experiments on the mechanical vibration theory
Experiments on various pendulums, bar-type oscillators and spring-mass systems
Damping, resonance and absorber effects in forced vibrations.
The Vibrations Frame offers the ideal working frame for all of the Universal Vibration apparatus experiment modules. The internal working dimension for mounting experiments is 1.22m x 0.76m. Manufactured from high quality, ergonomic aluminium profile, Vibrations Frame comprises solid side profiles for rigidly mounting experiment components and dual upper and lower members, which creates a mounting slot thus allowing the individual experiment components to be interchanged quickly and efficiently.
The Vibrations Frame comes fully assembled with no need for tooling or lengthy assembly.
Profile grooves create an accurate alignment of experiment components, and pre-assembled fasteners are integrated into the grooves for assembling of specific experiments within the range.
The vibrations are induced by inhomogeneous flow fields. The accessory set induces the vibrations magnetically. Three fan rotors with differing numbers of blades can be investigated. Vibration measurements on fans and blowers play a major role in field monitoring operations. In addition to the usual signals caused by bearings and imbalance, the vibrations induced by the fan blades can be measured. A guard plate covers the rotating fans. Just as in actual practice, the fan model can also be driven directly via a flexible coupling or by the belt drive. An obliquely-mounted inertia disk is used to investigate the gyroscopic effect.
....
An elastic, vibration insulating installation of the machine avoids the transmission of harmful vibrations to the surroundings. The can be used to investigate the problems of foundations and vibration isolation using a practical example. This is installed on a foundation using springs and dampers. The foundation represents the surroundings and can be used to measure the effectiveness of the vibration isolation. An indispensible element of machine design is targeted reduction of vibrations. To do this, vibrations are generated and measured on a foundation. Springs are then used to try out different tunings and vibration absorbers are used to investigate absorption effects. This double vibration isolation, combined with the high fixed weight of the frame, guarantees vibration-free laboratory operation, even under unfavourable experimental conditions. Additional helical springs connect the foundation to the actual frame of the trainer.
....
Vickers Hardness Tester is fully automatic using a motorised system. The accurate load is applied on a diamond penetrator by means of a lever and weights. After a specific lapse of time the load is removed automatically. Vickers Hardness Tester is designed specifically for Vickers hardness testing. The testing range is very wide, from soft metal such as lead, upto the hardest, like hardened steel.
The sample specimen is then compared with the test piece and the diamond indentation is projected on the measuring screen. The diagonals of the indentation can be measured by means of the micrometer screw of the projection screen. The robust machine frame is designed to accommodate the high precision loading system and an optical projection screen specimen is placed on a testing table.
Experimental Capabilities:
Vickers hardness testing
Suitable when lighter aprons will do
Grommets and bib are electronically heat-sealed for added strength
Nylon ties secure apron at back
Available with nylon-serged finished edges.
Lightweight and water repellent arm protection.
Heavy duty vinyl provides a comfortable fit for all day wear
Keeps skin and hair from contaminating product.
Protection against fats, oils, chemicals, liquids, dirt and grime
Resists snags, punctures and abrasion.
With heat-sealed elastic cuffs
6mil thick aprons have electronically welded binding strip around neck edge only; other edges are unhemmed
8mil thick aprons have electronically welded vinyl binding strip that covers all edges for smoother finish
Available with snap -on nylon ties
Neck ties, 15 in. long (38cm); waist ties, 29 in. long (74cm)
Blue.
With heat-sealed elastic cuffs
6 mil thick aprons have electronically welded binding strip around neck edge only; other edges are unhemmed
Blue
Neck ties, 15 in. long (38cm); waist ties, 29 in. long (74cm)
8 mil thick aprons have electronically welded vinyl binding strip that covers all edges for smoother finish.
Dimension (L*W*H CM): φ22.5
....
It is to be used with Universal Structural Frame. An elastic beam is supported at both ends by moment supports. Both supports permit the application and measurement of moments and rotations. The Virtual Work equipment is used for applying the principle of virtual work to the derivation of redundant reactions. A third support, vertical force support, is used for the case of two span continuous beam. The deflection and slope of the beam can be measured by dial indicators. A clamp on moment application device with a mean to counter balance the device weight is provided to apply a pure moment and measure rotation. The beam is loaded by weights.
....
Computer interface unit and software are included. The Virtual Work Computer Assist set has the same accessories as except Moment Supports are replaced by Moment Load Cells, and Vertical Force Support is replaced by Vertical Force Load Cell.
....
The flume is made of transparent glass, precision-built toensure parallel walls and a consistently accurate cross section along itslength. The Viscosity and Particle Drag apparatus is a simplefalling-sphere viscometer. The self-standing unit holds two glass tubes filled with the test fluids, for comparisons and to minismise draining and refillingof the fluids after experimentation. A sturdy steel square-section firmly supports the channel throughoutits length. It has a floor-standing frame that supports the working section ata convenient eye-level position for students. The back plate has a low-voltage backlightso students can easily see the test spheres through the fluid. Students fillthe two tubes with their chosen test fluid, then select a sphere of the correctdensity and size for the fluid. They drop the sphere into the test fluid at thetop of the glass tube. The valve systemminimises the fluid loss from the tube and helps when draining the tube afterthe tests are complete. Students may also make their own use shapes to test inthe unit. The shapes must fi t through the valve at the base (maximum 8 mm inany single dimension). They then use a stopwatch (included) to measure the timetaken for the sphere to fall a set distance down the tube. When the test spherereaches the bottom of the tube, it enters a valve that the students turns,dropping the sphere into a collection vial for recovery. The apparatus can be used with any fluid that can besafely handled and is chemically compatible with the wetted parts of theequipment - glass and PTFE. Suitable test fluids include water, thin machine oil,castor oil and motor oil.
....
Ideal for protecting visitors in industrial or medical settings.
Clear lens absorbs >99.9% of harmful UV light
Uncoated lens
Economical safety spectacles
100% impact-resistant polycarbonate wraparound unilens design with blue temples
Fits over most eye-glasses.
Ideal for protecting visitors in industrial or medical settings.
Scratch-resistant, Anti-fog, Anti-static.
Clear lens absorbs >99.9% of harmful UV light
Fit over prescription eyeglasses
Economical safety spectacles
100% impact-resistant polycarbonate wraparound unilens design with blue temples.
Visually manage and dispense PPE.
Durable and cleanable PETG construction.
Visual Refrigeration Training Unit operates on refrigerant. An electrical control box is mounted on the back panel and includes indicators/warning lamp, on/off contactor and overload, as well as residual current device for protection against earth leakage. Visual Refrigeration Training Unit comprise an air-cooled condensing unit with open type twin cylinder reciprocating compressor and a transparent plastic evaporator, clearly showing change of state of refrigerant from liquid to vapour phase. The unit also incorporates, Liquid/suction heat exchanger, Liquid line filter drier and sight glass, HP/LP switches, Compound and pressure gauges, Suction and discharge service valves fitted, Liquid line hand wheel valve fitted for easy manual pump down of system. The following refrigerant flow control options may be selected by the use of hand wheel valves: Automatic Expansion Valve; Thermostatic Expansion Valve, Internally equalised; Capillary with Separate Filter Drier.
....
Open-channel flow demonstrated on 2 weirs
Flow around solid bodies demonstrated on four drag bodies
Flow through demonstrated with 3 differently shaped models
Experimental unit for visualisation of various flow processes
Optional operation via laboratory supply or as closed water circuit
Illuminated flow section with transparent front panel
Contrast medium: ink.
Visualisation of flow fields by using electrolytically generated hydrogen bubbles
Platinum wire as cathode and stainless steel plate as anode for electrolysis
Different flow velocities via variable-speed circulating pump
Flow straightener and glass spheres ensure consistent and low-turbulence flow
Shallow water channel fitted with indirect LED illumination along the experimental section
Setting power (with display), pulse and pause duration of the power and the flow velocity in the water channel
Various models are included: aerofoil, rectangle, straight plate, curved plate, cylinder (various sizes), Various models for changes in cross-section.
Visualisation of two-dimensional seepage flows and investigation of water pressure at various models closed water circuit
Experimental section with tempered glass viewing window
Fine-mesh screen to separate the experimental section from the feed and discharge chamber
Height-adjustable overflows in the feed and discharge to adjust the water levels
Fluoresceine as a contrast medium
Retaining wall" and "foundation" models for demonstration of the water pressure
Instruments: tube manometers, tubes on the "foundation" and "retaining wall" models
14 measuring connections with filters to detect the groundwater levels in the experimental section
Sheet pile" model for visualisation of streamlines.
