Indication Instrument in a Liquid Expansion System: Bourdon Tube

The correct answer for the indication instrument in a liquid expansion system is option 'B', which is the Bourdon tube. The Bourdon tube is a mechanical device commonly used as a pressure gauge in various applications, including liquid expansion systems.

Explanation:

The Bourdon tube is a type of pressure measuring device that converts pressure into mechanical displacement. It consists of a curved tube, usually made of metal, which is closed at one end and connected to the system where pressure needs to be measured. As the pressure inside the system increases, it causes the Bourdon tube to deform or straighten.

Working Principle:

When the pressure inside the system increases, it exerts a force on the inside surface of the Bourdon tube. The tube tends to straighten due to this force, and this straightening is proportional to the pressure applied. The movement of the Bourdon tube is then transmitted to a pointer or a digital display, providing a visual indication of the pressure.

Advantages of Bourdon Tube:

1. Accuracy: Bourdon tubes provide accurate pressure readings over a wide range of pressures.
2. Wide Range: They can measure both low and high pressures effectively.
3. Simple Design: Bourdon tubes have a simple design and are relatively easy to manufacture.
4. Durability: They are robust and can withstand harsh environments.
5. Cost-effective: Bourdon tubes are cost-effective compared to other pressure measuring devices.

Applications of Bourdon Tube:

1. Liquid Expansion Systems: Bourdon tubes are commonly used as indication instruments in liquid expansion systems, such as liquid-filled thermometers, where the expansion of liquid is used to measure temperature.
2. Pressure Gauges: They are widely used as pressure gauges in various industries, including oil and gas, chemical processing, and HVAC systems.
3. Hydraulic Systems: Bourdon tubes are used in hydraulic systems to monitor and control the pressure.
4. Process Control: They are used in process control systems to measure and regulate pressure in industrial processes.

Overall, the Bourdon tube is a reliable and widely used indication instrument in liquid expansion systems due to its accuracy, versatility, and durability. It provides an effective means of measuring pressure and is suitable for various applications.