BEng Chemical Engineering Instrumentation Part 5: Measurement of Process Variables

These flashcards cover key terms and concepts related to the measurement of process variables in chemical engineering instrumentation.

Temperature

A measure of heat or thermal energy, commonly measured in degrees using various scales including Celsius, Fahrenheit, and Kelvin.

Thermal Expansion

The tendency of matter to change its shape, area, and volume in response to a change in temperature.

Thermocouple

A device made of two different conductors that produce a voltage proportional to the temperature difference between its two junctions.

Bimetallic Principle

The bending of a bimetallic strip composed of two different metals that expand at different rates when heated.

Thermography

The use of infrared imaging to detect and measure temperature variations on the surface of an object.

Hydrostatic Pressure

The pressure exerted by a fluid at equilibrium due to the force of gravity.

Capacitive Level Measurement

A method of measuring the level of a substance in a container by determining the capacitance changes caused by the amount of substance.

Strain Gauge

A device used to measure the amount of strain on an object; commonly used in pressure sensors.

Density

The mass per unit volume of a substance, typically expressed in kilograms per cubic meter (kg/m³) or grams per cubic centimeter (g/cm³).

pH Measurement

The determination of the acidity or alkalinity of a solution on a logarithmic scale of 0 to 14, where lower values indicate acidity, and higher values indicate alkalinity.

Intelligent Sensors

Sensors that integrate advanced signal processing, data fusion, and intelligent algorithms to autonomously perform measurement and analytical functions.

Electromagnetic Flowmeter

A device that measures the flow of conductive liquids through electromagnetic induction.

Ultrasonic Flowmeter

A flow measurement device that uses ultrasonic signals to measure flow velocity by analyzing the transit time of sound waves.

Coriolis Flowmeter

A mass flow measurement device where the mass flow rate is determined from the changes in oscillation caused by flow through vibrating tubes.

Resistance Temperature Detector (RTD)

A temperature sensor whose resistance varies with temperature; often made with platinum for its stable and repeatable characteristics.

Thermal Conductivity Detector (TCD)

A detector used in gas chromatography that measures changes in thermal conductivity of a gas sample compared to a reference.

Sampling Lance

A tool used to extract samples from a bulk material or liquid in industrial applications.

Mercury-in-Glass Thermometer

A thermometer invented by Daniel Gabriel Fahrenheit that uses mercury in a glass tube to indicate temperature changes.

Liquid Column Manometer

A device that measures pressure using a column of liquid in a U-tube.

Vortex Flowmeter

A device that measures fluid flow based on the vortices formed behind a bluff body placed in the fluid stream.