According to the second law of thermodynamics, heat is always transferred from the higher energy level to the low energy level. If the temperature of a body does not change despite continuous addition or removal of heat, this is known as steady-state heat conduction. Heat conduction is one of the three basic forms of heat transfer.
Features:
Effect of different metals on heat conduction.
The Radial Heat Conduction accessories have been designed todemonstrate the application of the Fourier rate equation to simple steady-stateconduction radially through the wall of a tube.
Hardware Description:
The accessory comprises a soliddisk of material, which is heated at the centre and cooled at the periphery tocreate a radial temperature difference with corresponding radial flow of heatby conduction.
Six K-type thermocouples arepositioned at different radii in the heated disk to indicate the temperaturegradient from the central heated core to the periphery of the disk.
The arrangement, using a solid metal disk with temperature measurementsat different radii and heat flow radially outward from the centre to theperiphery, enables the temperature distribution and flow of heat by radialconduction to be investigated.
The heater power and the cooling water flow rate are controlled via,either from the front panel or from the computer software. These are controlledmanually.
A control valve permits the flowof cooling water to be varied, if required, over the operating range of 0-1.5l/min.
The cooling water flow rate ismeasured by a turbine type flow sensor .
An optional cooling water flowrate sensor Set 2 is available upon request for the connecting directly intothe service unit.
The radial distance between eachthermocouple in the disk is 10mm.
Quick-release connectionsfacilitate rapid connection of the cooling tube to a cold water supply. Apressure regulator is incorporated to minimise the effect of fluctuations inthe supply pressure.
The electric heater and thermocouples connect to sockets on the Heat Transfer Experiments Base Unit, which also supplies the cold water feed and drain for the heat sink Students turn on the cooling water flow and adjust the heater power until the experiment reaches equilibrium. This experiment has a solid brass disc with an electric heater at its centre and a circular cross section cooling tube around its circumference. At equally spaced radii on the disc, seven thermocouples measure the temperature as the heat conducts radially outwards from the heater. Insulation around the disc reduces heat loss by convection and radiation, so that the results should match the theory for simple radial conduction only. It mounts on a base plate with a clear schematic of the experiment layout.
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Heat conduction is one of the three basic forms of heat transfer. Basic experiments for targeted teaching on the topic of heat conduction in fluids. Such teaching should discuss the fundamental differences between gases and liquids. According to the second law of thermodynamics, heat is always transferred from the higher energy level to the low energy level.
Features:
Effect of different fluids on heat conduction.
Heat Conduction And Convection allows basic experiments on both forms of heat transfer: heat conduction and convection. Heat conduction and convection are among the three basic forms of heat transfer and often occur together.
Features:
Effect of heat conduction and convection on heat transfer.
The cold section is of identical dimensions to the hot end and is water-cooled. Both the heated and cooled ends are each fitted with three thermo couples at 15mm intervals to measure the temperature gradients along the bars.
A small-scale accessory that allows experimental investigation of linear heat conduction and the measurement of the thermal conductivity of various solid conductors and insulators.
The hot end uses a nominal 65W heater (operating at 240v maximum), which is fitted with a high temperature limit switch. The power supplied to the heater is controlled and measured by the Heat Transfer Service Unit .
An insulated, 25mm diameter brass heated section and cooling section that may be either clamped together, or assembled with one of four insulated intermediate sections or test specimens between the interfaces.
A small-scale accessory to introduce students to the principles of radial heat conduction, and to allow the conductivity of a solid brass disk to be measured
Thermally insulated to minimize errors due to heat loss.
Includes an electronic proportioning solenoid valve to control the cooling water flow rate, a pressure regulator and a water flowmeter.
Comprises a brass disk with a heater at the centre and a cooling water tube attached to the periphery.
Includes a water pressure regulator and a manually operated valve to control the flow rate.
Water flow rate variable up to 1.5 litres/ minute.
Conduction disk is 110mm diameter and 3.2mm thick
Six thermocouples measure the temperature gradient between the heated centre and the cooled periphery of the disk.
Heater power variable up to 100 Watts.
A Dewar vessel prevents the exchange of heat with the surrounding environment. The specimens are equipped with several temperature measuring points. The fundamental laws of steady-state thermal conduction in solid bodies can be investigated with this experimental unit. The heat transfer rate is determined via the current and voltage of the heater. The specimens are arranged between an electrical heater and a water-cooled plate.
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The heating section, cooling section and one of the intermediate sections are fitted with thermocouples (eight in total) evenly spread along the length of the assembled conduction path.
A small-scale accessory designed to introduce students to the principles of linear heat conduction, and to enable the thermal conductivity of various solid conductors and insulators to be measured.
Includes a water pressure regulator, an electronic proportioning solenoid valve to control the cooling water flow rate and a water flow meter.
Comprises a heating section, cooling section plus four intermediate section conductor samples and two insulator samples.
All sections are insulated to minimize errors due to heat loss.
Includes a water pressure regulator and a manual flow control valve.
Heater power variable up to 60 Watts.
Water flow rate variable up to 1.5l/min.
Heating and cooling sections, 25mm diameter.
A comprehensive instruction manual is supplied.
The accessory is mounted on a PVC baseplate, which is designed to stand on the bench top and connect to the Heat Transfer Service Unit without the need for tools.
The medium for the experiment is fed through a gap. The gap between the two elements was selected so that the transfer of heat due to convection can be ignored. It comprises a cylindrical heat exchanger with a heated inner cylinder made of aluminium and a water-cooled jacket. Due to the low temperatures and the polished surfaces, the radiation portion of the heat transfer is also negligible. This experimental unit enables experiments to be performed on steady-state thermal conduction in liquid and gaseous materials. Temperature sensors measure the temperature difference.
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The electrical heat source is controlled electronically. The heat sink is water-cooled. The temperatures of the heat source, cooling water and specimen are indicated. An interchangeable cylindrical specimen is fitted between a heat source and a heat sink. The specimen is prefitted with twelve thermocouples distributed along its length. This unit is used to investigate steady-state and non-steady-state heat conduction processes. There are also displays for heating capacity and cooling water flow rate. In addition, it is possible to transfer the measured data to a computer via USB and display the data on the computer. The software is included. The thermal conductivity can be calculated using the measured data.
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Used to distinguish the thermal conductivity of metal sheets. The heat conducting rods are composed of brass, red copper, iron, aluminum and stainless steel.
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Linear heat conduction: 3 measuring objects, heating and cooling element, 9 temperature measuring points
Radial heat conduction: brass disc with heating and cooling element, 6 temperature measuring points
Examination of heat conduction in solids
Experimental setup consisting of experimental unit and display and control unit
Electric heating element
Cooling with mains water.
It consists of brass, iron, aluminum, red copper and stainless steel. It is used to distinguish different metal rod thermal conductivity.
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