The Armfield HT10XC is a service unit, which can be used in conjunction with a range of small scale accessories for a wide range of demonstrations into the modes of heat transfer.

The factors that affect heat transfer can be investigated and some of the practical problems

associated with the transfer of heat can be clearly demonstrated

The heat transfer accessories may be individually connected to the HT10XC service unit, which provides the necessary electrical supplies and measurement facilities for investigation and comparison of the different heat transfer characteristics.

A specific feature of the HT10XC is that it incorporates the facilities and safety features to

allow the accessories to be remotely controlled from an external computer, where this is appropriate. With suitable (user provided) software, this means that the equipment can be

operated remotely, for instance over an intra-net or even over the internet. All the facilities can also be accessed locally using the front panel controls and display.


Single phase mains electrical supply:

HT10XC-A: 230V, 50Hz, @ 5A

HT10XC-B: 115V, 60 Hz, @ 10A

HT10XC-G: 220V, 60Hz, @ 5A

Shipping Specification

HT10XC only

Volume: 0.05m³

Gross Weight: 15kg

Overall dimensions

HT10XC only

Height: 0.24 m

Width: 0.32 m

Depth: 0.39 m


Computer Controlled Combined Convection and Radiation




A hot surface loses heat (heat is transferred) to its surroundings by the combined modes of convection and radiation. In practice these modes are difficult to isolate and therefore an analysis of the combined effects at varying surface temperature and air velocity over the surface provides a meaningful teaching exercise.

The heated surface studied is a horizontal cylinder which can be operated in free convection or forced convection when located in the stream of moving air. Measurement of the surface temperature of the uniformly heated cylinder and the electrical power supplied to it allows the combined effects of radiation and convection to be compared with theoretical values. The dominance of convection at lower surface temperatures and the dominance of radiation at higher

surface temperatures can be demonstrated as can the increase in heat transfer due to forced convection.

On the HT14C, the heater power and the air flow are controlled via the HT10XC, either from the front panel, or from the computer software. On HT14 these are controlled manually.


HT14: HT14C:

Height: 1.20m Height: 1.20m

Width: 0.35m Width: 0.49m

Depth: 0.30m Depth: 0.44m


HT14: HT14C:

Volume: 0.1m3 Volume: 0.2m3

Gross weight: 9kg Gross Weight: 13kg











The Armfield Radial Heat Conduction accessories have been designed to demonstrate the application of the Fourier Rate equation to simple steady-state conduction radially through the wall of a tube. The arrangement, using a solid metal disk with  temperature measurements at different radii and heat flow radially outwards from the centre to the periphery, allows the temperature distribution and flow of heat by radial conduction to be investigated.

On the HT12C the heater power and the cooling water flow rate are controlled via the HT10XC,

either from the front panel or from the computer software. On the HT12 these are controlled manually.


HT12C requires HT10XC Computer Controlled

Heat Transfer Service Unit.

HT12 requires either HT10XC or HT10X Heat

Transfer Service Units.


Cold water supply: 1.5 litres/min @ 1 Barg

All electrical requirements are obtained from the

service unit.


HT12: HT12C:

Height: 0.19m Height: 0.19m

Width: 0.35m Width: 0.43m

Depth: 0.18m Depth: 0.18m


HT12: HT12C:

Volume: 0.03m3 Volume: 0.04m3

Gross weight: 5kg Gross Weight: 6kg




























A range of small scale heat exchangers, designed to illustrate the principles and techniques of indirect

heat transfer between fluid streams. Different types of heat exchanger can be mounted on a common

bench-top service unit. Small scale versions of commonly used industrial heat exchangers are

available (including plate, tubular and ‘shell and tube’) for analysis and comparison. The equipment is

controlled by a user supplied personal computer, which serves as the operator interface. Full data

logging, control and educational software is supplied with the equipment. In addition, the equipment

has been fitted with failsafe systems, including a watchdog circuit, which allows for safe operation

from a remote computer.


Single phase mains electricity supply:

HT30XC-A: 230V, 50Hz, 10Amp

HT30XC-B: 115V, 60Hz, 20Amp

HT30XC-G: 230V, 60Hz, 10Amp

Cold water supply and drain:

5 Litres/minute at 1bar Gauge (Min)


Volume: 0.33m³

Gross weight: 33kg


Height: 0.45m (service unit only)

Width: 1.0m

Depth: 0.5m






The shell and tube heat exchanger is commonly used in the food and chemical process industries. This type of exchanger consists of a number of tubes in parallel enclosed in a cylindrical shell. Heat is transferred between one fluid flowing through the tubes and another fluid flowing through the cylindrical shell around the tubes.



The miniature exchanger supplied is designed to demonstrate liquid to liquid heat transfer in a 1-7 shell and tube heat exchanger (one shell and 7 tubes with two transverse baffles in the



Volume: 0.06 m³

Gross Weight 5 kg

Armfield Accessories

HT30XC or HT30X Heat Exchanger Service Unit

Overall dimensions

Height 0.19m

Width 0.43m

Depth 0.39m














The Armfield Linear Heat Conduction accessory has been designed to demonstrate the application of the Fourier Rate equation to simple steady-state conduction in one dimension.

The unit can be configured as a simple plane wall of uniform material and constant cross sectional area or composite plane walls with different materials or changes in cross sectional area to allow the principles of heat flow by linear conduction to be investigated.

Measurement of the heat flow and temperature gradient allows the thermal conductivity of

the material to be calculated.

The design allows the conductivity of thin samples of insulating material to be determined.


Experimental Capabilities

• Understanding the use of the Fourier Rate Equation in determining rate of heat flow through solid materials

• Measuring the temperature distribution for steady-state conduction of energy through a

uniform plane wall and a composite plane wall

• Determining the constant of proportionality (thermal conductivity k) of different materials

(conductors and insulators)

• Measuring the temperature drop at the contact face between adjacent layers in a composite

plane wall (contact resistance)

• Measuring the temperature distribution for steady-state conduction of energy through a

plane wall of reduced cross-sectional area

• Understanding the application of poor conductors (insulators)

• Observing unsteady-state conduction (qualitative only)


Armfield equipment


HT10X Heat Transfer Service Unit

Armfield Accessories


HT10X-304 Educational Software with USB interface



Cold water supply:

1.5 litres/min @ 1 Barg

Overall dimensions


Height: 0.29m

Width: 0.43m

Depth: 0.21m








The UOP20 family is a modular system of teaching evaporators for chemical engineering

departments. Using the various modules a wide range of configurations can be implemented:

rising; single or double effect; forward, backward or parallel feed.

The evaporators are fully computer compatible, supplied with educational software including

process control and data logging facility, suitable for use with a personal computer.

Evaporator Service Unit (UOP20X)

The Evaporator Service Unit (UOP20X) contains all the services and facilities to implement a laboratory evaporation system. It comprises a feed pump and pre-heat system, vacuum pump, condenser, collection vessels and control console containing a full set of instrumentation, all mounted in a sturdy steel framework

Two mounting positions are provided for the modular evaporation columns.

Two basic variants of the UOP20X are available, dependent on whether it is required to use steam as the process heating source or pressurised hot water:

The UOP20X-STM includes a steam control valve and steam pressure gauge. It is powered from an external steam source such as the Armfield UOP10 or any other suitable laboratory steam supply.

The UOP20X-PHW includes a pumped recirculating pressurised hot water system complete with integral 3 term temperature controller. Therefore service requirements are simply an appropriate electrical supply and a cooling water supply.

Each UOP20X includes a control console, containing all of the electrical components,

controls and displays for the evaporator. Twelve process temperatures, three conductivity

readings and the vacuum level can be displayed.

It also includes pre-heat temperature controller, speed controls for the feed pump and recirculation pumps, the computer interface and electric mains switching controls.

When coupled to a suitable PC, using the two USB interfaces, a wide range of sophisticated

data logging and educational software facilities is available. Furthermore the UOP20 can be

operated in remote control mode, whereby the majority of the control panel functions can be

implemented directly from the PC. Although a wide range of products may be concentrated

in the evaporator, the software includes algorithms so that when potassium chloride is used the computer display indicates the product concentrations directly. These are calculated in

real-time from the temperature and conductivity readings. The computer software also

includes a fully configurable PID controller for performing process control experiments.

The vacuum pump and display can be used to show the effect of vacuum on evaporation

temperature. In a double effect system the vacuum is applied to the second stage.

Evaporator Columns

Each evaporator column contains a stainless steel evaporation tube, within an insulated

heated jacket for the hot water or steam. These are mounted on a back plate together with a

glass cyclone to separate the concentrated product from the evaporated steam.

Also included on the back plate of each evaporation column is a recirculation pump and

associated pipework, together with thermocouples to measure the temperatures of the product and heating fluid at a number of points. Two basic types of evaporation column are available:

UOP22, a rising film evaporation column.

A number of variants are defined for each column type, dependent on whether it is a first or second effect unit, and whether it is located in the first or the second position on the UOP20X

service unit.

UOP22-11 Rising Film Evaporation Column (1st effect, 1st position)

UOP22-22 Rising Film Evaporation Column (2nd effect, 2nd position)


Height: 2.5m

Width: 1.5m

Depth: 0.9m



including up to two evaporation columns:

Volume: 5m3

Gross weight: 450Kg max.

Evaporator Column Length: 1m

Pressurised Water Heater: 4KW

Feed Pre‐Heater: 2KW

Conductivity displays: 0‐100mS





It is essential that the three basic modes of heat transfer; Conduction, Convection and Radiation are

understood by students as a foundation for further studies involving heat transfer and temperature


The Hilton Heat Transfer Service Unit H111 may be connected to any of seven optional demonstration units each demonstrating a fundamental mode of heat transfer or a combination of modes of heat transfer and a range of experiments to reinforce the learning process.

The Hilton Heat Transfer Service Unit H111 is bench mounted, operates from a conventional single phase

electrical power supply and provides both control and instrumentation for each of the seven optional demonstration units.

The seven optional units are: -

Linear Heat Conduction                                   H111A

Radial Heat Conduction                                   H111B

Laws of Radiant Heat Transfer & Radiant Heat Exchange                                                          H111C

Combined Convection and Radiation              H111D

Extended Surface Heat Transfer               H111E



Electrical Specification


 A: 220-240 Volts, Single Phase, 50Hz(With earth/ground).

 B: 110-120 Volts, Single Phase, 60Hz(With earth/ground).


Service Unit

Net Weight: 12.3 kg.

Packing Case Volume: 0.22m3






A bench top accessory designed to allow students to experimentally investigate both free (natural)

convection and forced convection. The accessory includes a small, variable velocity wind tunnel with

a digital velocity meter and a central aperture. Three plates with integral heaters and temperature sensors are also supplied that are designed to fit in the central aperture in the wind tunnel.

A heated flat plate with surface thermocouple may be directly compared with a similar pinned plate and finned plate also fitted with a surface thermocouple. In addition to expanding understanding of the heat transfer enhancement from extended surfaces, the pinned and finned plates each have three thermocouples arranged at intervals along a fin and a pin. This allows investigation of the temperature distribution along the extended surfaces.


Net Weight 30kg

Packing Case Volume 0.28m3


Height: 1300mm

Depth: 300mm

Width: 350mm

Weight: 20kg





The Cussons P7665 Boiler Control Demonstration Unit has been designed to demonstrate clearly and

simply a range of boiler control sequences relating to oil or gas fired boilers. Since steam pressure is

‘simulated’ the whole functioning of a boiler may be studied in a relatively safe situation. The Demonstration Unit can act as a valuable teaching aid for the training of boiler operating personnel in

the diagnosis of boiler system faults which may occur in practice.


Switch Fault

A Blower motor failure

B Ignition transformer failure

C Pilot flame solenoid failure

D Main flame solenoid failure

E Power failure

F Ignition circuit fuse failure

G Pressure gauge system fault

H Feedwater pump fault

I Pump fuse failure

J Pressure switch failed open

K Pressure switch failed closed

M Closed electrode probe short circuited

N Photocell operation fault


Gross weight: 410 kgs

Nett weight: 220 kgs

Case size: 134 x 96 x 193 cm