Cooling water quantity measuring system of chilled water

I. overview

With the increase of large buildings and modern buildings, the cooling system has been developed rapidly, and the demand for cold energy in industry and its industry has also promoted the development of centralized cooling system. Centralized cooling is the power plant which uses a cold medium (usually fresh water and salt water) to supply refrigeration to the user. In order to manage and calculate the operation of refrigeration equipment, it is necessary to measure the cooling capacity of the related nodes to settle the cold consumption of the users.

The measurement of freezing water cooling is the same as that of hot water, and the amount of cold can be regarded as negative heat. Because of the low temperature of the fluid, there are some differences in specific practices.

Two. Installation diagram of refrigerating water quantity measuring system

The chilled water used for air conditioning is generally 5-6 degrees centigrade, and chilled medium is fresh water. Cold water below 5 DEG C is served with brine or other cold media. The method for measuring the amount of chilled water in fresh water is based on mass flow measurement as shown below.

(1) in the flow measurement of frozen water, LD electromagnetic flowmeter has obvious advantages, and its characteristics are as follows:

The electromagnetic flowmeter measurement is not affected by the fluid density, viscosity, temperature, pressure and electrical conductivity.

The electromagnetic flowmeter tube without obstructing the flow of parts, no pressure loss, lower straight pipe section.

The electromagnetic flowmeter sensor can realize the instrument with grounding electrode, good grounding.

The electromagnetic flowmeter sensor uses the advanced processing technology, the instrument has good anti pressure ability

The LD series electromagnetic flowmeter lining choice: if water is frozen freshwater, can choose the rubber lining, low cost, if the chilled water for brine, must choose PTFE lining, if both measured chilled water and fresh water measuring saline, must choose PTFE lining, South FLDC electromagnetic flowmeter instrument control according to the production site, select the appropriate lining material.

The thermal resistance, the southern control instrument is used with high quality and high precision of a sheathed thermal resistance, precision can reach 0.2%, greatly improve the system accuracy, thermal resistance junction box with waterproof, long service life.

The XSR22 series heat accumulators according to the temperature and flow of all kinds of signal acquisition, display, control, transmission, communication, printing and other processing, a digital acquisition system and control system for conducting oil boiler, plumbing and heating system and heat exchange system, the quantity of heat and cold air conditioning units, buildings and change station and Thermotics Inc network heat metering, to realize the online measurement of heat and mass transfer, so as to provide the basis for enterprise energy management, energy consumption measurement, technology and economy.

(2) in addition to the electromagnetic flowmeter measurement, can also be used to measure the TUF series ultrasonic flowmeter, customers can choose according to the situation, the ultrasonic flowmeter heat metering system installation diagram as follows.

The TUP series ultrasonic flowmeter adopting international standard enthalpy calculation formula of heat (enthalpy difference method) measure the quantity of cold / heat, in order to satisfy the needs of different working conditions, can be divided into one type, split type, suitable for the air conditioning cold and heat exchanger station and building unit, and Thermotics Inc network heat metering etc..

The thermal resistance, the southern control instrument is used with high quality and high precision of a sheathed thermal resistance, precision can reach 0.2%, greatly improve the system accuracy, thermal resistance junction box with waterproof, long service life.

Schematic diagram of heat metering system for TUF series integrated ultrasonic flowmeter