1.HEAT TRANSFER IN NATURAL CONVECTION

The setup consists of a brass tube fitted in a rectangular duct in a vertical fashion. The duct is open at the top and bottom, and forms an enclosure and serves the purpose of undisturbed surrounding. One side of the duct is fitted with a transparent good quality Acrylic window for visualization. An electric heating element is kept in the vertical tube that in turns heats the tube surface. The heat is lost from the tube to the surrounding air by natural convection. The temperature of the vertical tube is measure by Temperature Sensors and displayed by a digital temperature Indicator with multi-channel switch. The heat input to the heater is measured by a ammeter and a Voltmeter and is varied by a variac. The tube surface is polished to minimize the radiation losses.

SPECIFICATIONS

• Pipe - Brass, 30-40 mm dia (OD),
• 300-500 mm, long fitted with cartridge heater inside.
• Enclosure size 200 mm x 200 mm x 500 mm with Perspex window
• Thermocouples fitted along the length of pipe.

Control Panel consisting of:

• Digital Ammeter - 0 to 10 Amp
• Digital Voltmeter - 0 to 230 Volts
• Multi Channel Digital Temperature Indicator
• Dimmer stat - 2 Amps.
• Mains ON/OFF switch

2.THERMAL CONDUCTIVITY OF INSULATING POWDER

The apparatus consists of a copper sphere in which a mica heater is fitted. This small sphere is surrounded by another copper sphere and the insulating powder to be tested is filled in between these two spheres. The head produced by heater is radially flows outwards in all directions through insulating powder. A digital temperature is used to measure temperatures of inner and outer sphere walls. An ammeter and voltmeter is provided to measure the input to heater. By knowing the input to heater, the conductivity of the insulating powder can be calculated. The unit is supplied with plaster of Paris powder, however any other powder can be tested with this unit.

• Inner sphere - copper, 100 mm dia.
• Outer sphere - copper, 200 mm dia.
• Heater - Mica heater placed in inner sphere Thermocouples - 4 Nos.

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch

3.HEAT TRANSFER IN FORCED CONVECTION

Convective heat transfer between a fluid and a solid surface takes place by the movement of fluid particles relative to the surface. If the movement of fluid particles is caused by means of external agency such as pump or blower that forces fluid over the surface, then the process of heat transfer is called forced convection

• Test pipe – 32mm G.I. pipe, 500mm long heated by band heater
• Centrifugal Blower to force air through test pipe with flow Control valve
• An orifice meter with differential water manometer.

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch

4.THERMAL CONDUCTIVITY OF INSULATING POWDER

The apparatus consists of a copper sphere in which a mica heater is fitted. This small sphere is surrounded by another copper sphere and the insulating powder to be tested is filled in between these two spheres. The head produced by heater is radially flows outwards in all directions through insulating powder. A digital temperature is used to measure temperatures of inner and outer sphere walls. An ammeter and voltmeter is provided to measure the input to heater. By knowing the input to heater, the conductivity of the insulating powder can be calculated. The unit is supplied with plaster of Paris powder, however any other powder can be tested with this unit.

• Inner sphere - copper, 100 mm dia.
• Outer sphere - copper, 200 mm dia.
• Heater - Mica heater placed in inner sphere
• Thermocouples - 4 Nos.

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch

5. EMMISSIVITY MEASUREMENT APPARATUS

All substance emits thermal radiation at all temperatures and also absorbs all or part of radiations coming from surrounding. The set up is designed to measure emmissivity of given material. It consists of set of two identical circular aluminum plates with mica heater sandwiched in between Test Plate and Black Plate. Both plates are housed in a enclosure to ensure steady atmospheric conditions. A Perspex window is provided to visualize the arrangement. In put to heater can be varied by dimmer stat and measure by help of Digital voltmeter and ammeter. Thermocouples are provided to measure the temperatures of these plates. By knowing the heat input and temperatures, one can calculate emmissivity of non-black surface and study the variation of emmissivity of test plate with respect to absolute temperature.

• Test plate: Polished aluminum of dia 125mm
• Reference plate : black aluminum of dia 125mm
• Wooden chamber with Perspex cover.
• Mica-insulated heaters for black and polished body.
• Set of Thermocouple - 3 Nos.

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch

6. PARALLEL FLOW /COUNTER FLOW HEAT EXCHANGER

Heat Exchanger is devices in which heat is transferred from one fluid to another. This apparatus is a tube in tube type concentric tube heat exchanger. Hot fluid flows through inner tube and cold fluid flows through outer tube. The Direction of cold fluid flow can be changed from parallel flow can be changed from parallel flow to counter flow with the help of valves. Temperature indicators with 5 thermocouples are provided to measure temperatures of incoming and outgoing cold and hot fluids.

• Outer tube of inter I.D. 25mm and length 1 metre.
• Inner tube of I.D. 10 mm and length 1.2metr.
• Thermocouples - 5 Nos.
• Arrangement for making parallel and counter flow.

• Hot water stroge tank.
• Cold water storage tank.
• Electric industrial heater of 2 KW.

• 5 Channels Digital Temp. Indicator range: 0-200oC
• Mains ON/OFF switch

7. STEFAN BOLTZMANN APPARATUS

The apparatus is designed to determine the Stefan’s Boltzmann constant .The Apparatus consists of a hemisphere of copper fixed on a Bakelite plate, the outer surface is surrounded by hot water jacket.

• Hemisphere made of copper, 200 MM DIA APPROX.
• Hot water jacket -250 mm dia, approx.
• Test disc – 25mm. dia., 1.6 mm thick copper
• Hot water Tank with 1.5 kw immersion heater

• Channels Digital Temp. Indicator range: 0-100oC
• Mains ON/OFF switch

8. HEAT TRANSFER THROUGH COMPOSITE WALL APPARATUS

This apparatus is used to calculate the heat transfer through composite wall.

• Composite Wall assembly consisting of-Cast Iron, Bakelite and Press wood of dia125mm, and 12mm thick.
• Heater-Nichrome wire heater wound on mica sandwiched between two aluminums plates.
• Test disc – 25mm. dia., 1.6 mm thick copper
• Enclosure for Assembly with Perspex window.
• Thermocouple - 6 Nos.

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch

9. PIN FIN IN NATURAL/FORCED CONVECTION APPARATUS

This apparatus is used to calculate the heat transfer coefficient of vertical pin in natural convection / forced convection.

• Vertical pin of dia 14mm and 130mm long fitted on a heater.
• Blower unit with orifice of 10 mm and manometer arrangement for flow measurement.
• Duct of size: 110 X 160 x 600 mm
• Pin type -Fin: Brass
• Ring type Heater
• Air blower

• DigitalVoltmeter– Range : 0 to 230V
• DigitalAmmeter– Range : 0 to 10 Amps
• Multi Channel Digital Temperature Indicator
• Dimmer stat : 02Amps
• Mains ON/OFF switch