The engine can be operated as an external ignition petrol engine or an auto-ignition diesel engine. The mode of operation can be changed by a few simple conversion steps. This allows the compression ratio to be adjusted over a wide range. The key feature is that the cylinder has been modified so that its height can be adjusted along with that of the cylinder head. Major technical modifications have been made to a standard water-cooled single cylinder engine to allow demanding issues in engine technology to be investigated by experiment.
Learning Objectives/Experiments:
Influence of ignition point on fuel consumption, power output, efficiency and exhaust gas composition
Comparison of diesel and petrol cycles
Plotting of torque and power curves
Determination of volumetric efficiency and lambda (fuel-air ratio)
Energy balances
Determination of friction loss (in passive mode)
Determination of specific fuel consumption
Determination of efficiency
Influence of compression on fuel consumption,
Power output, efficiency and exhaust gas composition.
The deflection of a spring depends on the load applied to it, an observation enshrined in Hooke's Law Applications of springs are found in spring balances which indicate loads by measuring spring deflections and in car suspensions where they absorb energy caused by wheel vertical movement due to potholes and bumps. Compression of Springs Apparatus are used in engineering to store energy or to provide restoring forces. Both compression and tension springs may be encountered.
Experimental Capabilitis:
Using the optionally available compressive spring set the dependence of spring stiffness on the wire diameter, spring diameter, length, number of turns and material can be observed and calculated
To determine spring stiffness using measured experimental results and formulae provided
To test the relationship between the load applied and the change in compressive length of a spring
Load versus compression graphs
Action of springs.
Anodized aluminum structure and panels of painted steel.
The unit includes wheels to facilitate its mobility.
Experimental unit for the training of apprentices for refrigeration area that allows the investigation of a refrigeration system with different expansion elements.
Diagram in the front panel with distribution of the elements similar to the real one.
Main metallic elements of stainless steel.
A Double-Compressor Air Conditioning Cycle Training Bench for studying the theoretical and practical aspects of the air conditioning cycle and the control of two compressors operating at different powers.
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Compressed air is often used instead of electrical energy, particularly in workplaces where there is a risk of explosion of combustible gases. The heat generated by compression is dissipated by cooling fins. Compressors are at the core of compressed air generator plants. These plants are used where compressed air is used as a source of energy. The compressor is driven by a V-belt. This enables references to be made between individual components and the Large-format drawings suitable for workshop practice can be attached to the display board at the rear of the trolley. A second fully functional compressor, permanently mounted to the workbench, can be used for demonstration purposes. A disassembled piston compressor is contained in the drawers of the trolley cabinet which also holds the tools and assembly aids, small parts and gaskets required for assembly.
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Wall mounted apparatus (for loading spiral springs in either tension or compression with direct gravitational loads) with accurately divided scale and vernier.
Supplied complete with four compression and four extension springs each approximately 18 cm long (7") long. Mass Hanger and Masses for (Hanger 1, Masses 13 x 1 kg)
Experimental Capability:
Modulus of rigidity for spring material.
Introduction to Spring Rate
Determines load and deflection relationships for close coiled springs.
An electrically-powered device designed to deliver high-flow (exceeding peak inspiratory flow) heated and humidified ambient air or air/oxygen to a neonatal patient as part of noninvasive ventilation (NIV); it may additionally be used with a water tank to produce bubble continuous positive airway pressure (bubble CPAP).
Continuous Positive Airway Pressure (Bubble CPAP) system for the non-invasive respiratory support of normal, premature or low-birth weight neonate with spontaneous breathing. The unit has an integrated pulseoximeter to measure the level of arterial oxygen saturation in blood.
It consists of a gas flow generator that entrains room air, an oxygen input, a heating element, and humidification chamber; it does not include CPAP controlling pressure sensors (i.e., not a full CPAP unit). It is intended for use by a healthcare provider on a spontaneously breathing patient in hospital settings.
Hermetic refrigerant compressors have welded sheet steel housing. The drive motor and refrigerant compressor are fitted in this capsule. The motor compressor is suspended by springs in the capsular housing which minimises the transmission of vibration to the capsule body, thereby reducing noise emission. Unlike open compressors, the refrigerant compressor is directly connected to the drive motor and therefore does not require any floating seal.
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These differ in their characteristics decisively from flow equipment which include the turbo compressors that are common in very large systems. In Piston Compressors the flow rate is mainly dependent on the displaced volume and speed. Smaller refrigeration systems usually have a Piston Compressor. Because the flow rate is a measure for the refrigeration capacity of the refrigeration system, the properties of the compressor are important for the capacity of the whole system. Piston compressors are positive displacement machines. Due to the unavoidable dead space the flow rate drops with increasing pressure ratio.
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Refrigeration systems with two-stage compression are used for the generation of particularly low temperatures. Therefore, two compressors are connected in series, with each compressor only having a relatively low pressure ratio. At very low temperatures large pressure differences are required between the evaporator and condenser. In a compressor the volumetric efficiency drops significantly at high pressure ratios. In addition, intercooling between the low pressure compressor and the high pressure compressor reduces the outlet temperature of the compressor to harmless values and improves the efficiency of the compression. This makes a more favourable dimensioning of the low pressure stage compressor possible. Due to the large specific volume it requires a larger capacity at lower drive power.
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The Compression Ratio can be changed without stopping the engine and without altering the combustion chamber geometry by means of a specially designed tilting cylinder block arrangement. Setup is provided with necessary instruments for combustion pressure and crank-angle measurements. Computerized Variable Compression Ratio Engine Test Bed allows to perform experiments concerning this kind of engines. The unit consists of single cylinder, four stroke, Variable Compression Ratio (VCR) engine connected to eddy current type dynamometer for loading. Provision is also made to interface airflow, fuel flow, temperatures and load measurement. Rota meters are provided for cooling water and calorimeter water flow measurement. The test bed includes a stand-alone panel box consisting of air box, two fuel tanks for duel fuel test, manometer, fuel measuring unit, transmitters for air and fuel flow measurements, process indicator and engine indicator.
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The refrigeration circuitry includes a water cooled condenser complete with isolating valves, manual expansion valve, evaporator, variable area flowmeter for mass flow of refrigerant, filter/drier unit, sight glass and over pressure cut-out for unit protection. The unit is designed to use Tetrafluoroethane as the refrigerant with a twin cylinder reciprocating compressor, belt driven by the variable speed dynamometer.
The evaporator coil is mounted in an electrically stirred water/glycol mixture contained in a thermally insulated, stainless steel tank. The water/ glycol mixture is protected from over temperature conditions by a thermostat should the heater should be left on when the compressor is not circulating refrigerant. Heating of this water/glycol mix is infinitely variable enabling balanced experimental conditions over a wide range of temperatures to be obtained.
Experimental Capabilities:
Determine the Mechanical, Thermodynamic (Isentropic) and Volumetric efficiencies.
Estimate the rate at which heat is transferred to the system from the surrounding environment.
Determine the energy flows and coefficient of performance for given operating instructions.
Operate the refrigeration unit over a range of conditions.
Estimate the Heat Transfer Coefficient.
Compile an energy balance under light load and full load conditions.
Examine the behaviour refrigerating cycle under variable loads and speeds.
The electrical components for the start and operation of a refrigerant compressor are clearly visibly arranged in a transparent showcase and already wired. The capacitor and start-up relay required for the motor are examined. Identifying electrical faults in refrigeration systems requires comprehensive knowledge this knowledge includes the design and operation of the individual electrical components as well as the reading of circuit diagrams. It helps to acquire this knowledge. The simulation of 15 different faults, e.g. coil fracture in the motor, short circuit in the operating capacitor or welded contacts in the start-up relay, is possible. Typical protection devices, such as circuit breaker and automatic fuse, are also arranged clearly visible.
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The Compression Ratio can be changed without stopping the engine and without altering the combustion chamber geometry by means of a specially designed tilting cylinder block arrangement both during gasoline running and during Diesel running. Computerized Variable Compression Ratio Multifuel Engine Test Bed allows to perform experiments concerning this kind of engines. The unit consists of single cylinder, four stroke, Variable Compression Ratio (VCR) engine connected to eddy current type dynamometer for loading. Setup is provided with necessary instruments for combustion pressure and crank-angle measurements. The test bed includes a stand-alone panel box consisting of air box, two fuel tanks for duel fuel test, manometer, and fuel Measuring unit, transmitters for air and fuel flow measurements, process indicator and engine indicator. Rota meters are provided for cooling water and calorimeter water flow measurement. These signals are interfaced to computer through engine indicator for pv diagrams. Provision is also made to interface airflow, fuel flow, temperatures and load measurement.
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Single-stage compressor, air-cooled, with fan flywheel, intake filter and pipe unions
Assembly exercise for engineering training
Compressor consisting of piston and cylinder, housing, driving gear, cylinder cover with valves
Complete, disassembled piston compressor with small parts set and 6 assembly jigs in a storage case.
Compressometer Extensometer consists of a central ring for the diametrical extension measure to be fixed on the compressometer. To measure both axial deformation and diametrical extension of cylinder specimens dia. 150x300mm, 160x320mm, 8x 12 under compression stress, by determining the elastic modulus.
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An electrically powered device designed to deliver high-flow (exceeding peak inspiratory flow) heated and humidified ambient air or air/oxygen to a neonatal patient as part of non-invasive ventilation (NIV); it may additionally be used with a water tank to produce bubble continuous positive airway pressure (bubble CPAP). It is intended for use by a healthcare provider on a spontaneously breathing patient in hospital settings. It consists of a gas flow generator that entrains room air, an oxygen concentrator, a heating provision, and humidification chamber; it does not include CPAP controlling pressure sensors.
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Pressure vessel with adjustable pressure switch and manometer
Switch box with controls and ammeter to indicate current consumption
Unit for functionality testing of the piston compressor from assembly exercises
Safety devices: pressure switch, safety valve, protective screen for belt drive, emergency-off switch
Driven by electric motor and belt drive
Single-phase electric motor on adjustable carriage.
Compressometer For Cylinders dia. 100x200mm; dia. 112,8x220mm; dia. 4x8.
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