The steam emerging from the separating calorimeter may still contain some water vapor, meaning it is not completely dry. For a throttling calorimeter, the steam exiting the throttle valve must be superheated or at least dry saturated. This limits the accurate calculation of the dryness fraction, which is based on the steam pressure in the main steam line. Even though steam may still be damp after passing through the throttle valve, it won’t be overheated if used. Therefore, the throttling calorimeter alone cannot help determine the dryness fraction of the steam. To address this, we use both independent and throttling calorimeters. The steam is passed through a separating calorimeter, where most of the moisture is removed, making it relatively drier, and then through a throttling calorimeter, where superheating occurs without affecting the overall heat output. The temperature and pressure of the steam after throttling are measured using a thermometer and a manometer.
The system includes a calorimeter that separates and throttles energy. A steam generator is positioned at the bottom of the device. A thermostat knob on the front of the unit controls the temperature in the steam generator. Steam from the generator first passes through a calorimeter that removes most of the water, making the steam drier, before being sent to another calorimeter for superheating. After passing through a heat exchanger, the superheated steam is then condensed.
Experimental Objective
The main objective of this experiment was to determine the dry fraction of the wet steam using a separating and throttling calorimeter
Arrangement of various components for set up of throttling and separating calorimeter
Separating Calorimeter
The inner and outer chambers, which are concentric, are connected at the top by a hole. As the steam passes through the metal baskets with multiple holes, the water vapor separates due to the increased momentum, entering the chamber. The relatively dry steam from the inner chamber then rises and falls in the annular space between the two chambers before entering the throttling calorimeter.
Throttling Calorimeter
It features a narrow throat, with pressure and temperature measured using a manometer and thermometer. After the throttling process, the steam passes through a heat exchanger, and the condensate is collected.
Utilities Required Other than above Supply