The core and the sleeve are arranged so that a uniform narrow annular gap is created between the two parts, which is filled by the liquid or gas to be analysed. The unit comprises a cylindrical, electrically heated, nickel-plated aluminium core surrounded by a nickel-plated aluminium sleeve.
The temperature on each side of the fluid is measured by thermocouples in the surface of the core and the sleeve. Both versions incorporate an insulated jacket to minimise heat exchange from and to the atmosphere. Adds an electronic proportioning valve and flow meter to vary and measure the flow using.
Measurement of the temperature difference between the heated and cooled surfaces together with the power supplied to the heater (measurement of DC voltage and current) using allows the conductivity of the fluid to be calculated. The fluid to be tested is injected into the annular gap between the heated core and the cooled jacket using a hypodermic syringe. The surface area and thickness of the fluid sample remain constant during all tests.
Features:
Concentricity of the heated and cooled surfaces is accurately maintained using a spiral insulator
Thickness of the fluid sample is restricted to 0.5mm to minimise convection in the fluid sample
ArmSoft software is supplied, with separate exercises for determining the thermal conductivity of liquids and gases
Trapped bubbles of the previous liquid or gas sample are prevented by the spiral flow path when injecting a different liquid or gas.
