Definition
A cooling circulating water machine is a device that provides a constant temperature circulation of cooled liquids through a refrigeration system. It is usually composed of components such as compressors, evaporators, condensers, circulation pumps, temperature control systems, and water tanks, which can continuously supply temperature-stable cooling media to laboratory instruments or industrial equipment to maintain the temperature conditions required for their normal operation.
How it works:
The cooling circulating water machine works based on the principle of vapor compression refrigeration cycle. The refrigerant is compressed into a high-temperature and high-pressure gas in the compressor, which dissipates heat to the environment as it flows through the condenser and condenses into a high-pressure liquid. Subsequently, the expansion valve throttles and reduces the pressure, becoming a liquid refrigerant with low temperature and low pressure and entering the evaporator. In an evaporator, the refrigerant absorbs heat from the circulating water and evaporates it into gas, reducing the temperature of the circulating water. The cooled circulating water is transported by the pump to the external equipment for heat exchange, and after absorbing heat, it is returned to the water tank to complete the cycle. The temperature control system monitors the water temperature through sensors and regulates the operation of the compressor or the operation of the heating element to achieve temperature stability.
Measurement and performance evaluation methodology
The performance evaluation of cooling circulating water is usually based on parameters such as cooling capacity, temperature stability, flow rate, and pressure. The cooling capacity can be calculated by measuring the temperature difference and flow rate of the inlet and outlet of circulating water, and the formula is: Q = c * ρ * V * ΔT, where Q is the cooling capacity, c is the specific heat capacity of water, ρ is the density of water, V is the volume flow, and ΔT is the temperature difference between inlet and outlet. Temperature stability is assessed by running for a long time at a set temperature point and recording a range of temperature fluctuations. Flow and pressure are measured directly using a flow meter and pressure gauge. Relevant tests can refer to international standards such as ISO 5151 and domestic machinery industry standards for refrigeration equipment performance testing.
Influencing factors
The performance of a cooling circulating water machine is affected by various factors. Too high ambient temperature may lead to a decrease in the heat dissipation efficiency of the condenser, which in turn affects the cooling effect. Insufficient purity and anti-corrosion treatment of circulating water may cause scale or corrosion of pipelines, reducing heat exchange efficiency. Improper equipment selection and load, such as insufficient or excessive cooling capacity, will affect temperature control accuracy and energy consumption. In addition, the design and insulation measures of the circulation pipeline will also affect the heat loss and temperature stability of the system.
Applications:
Cooling circulating water machines are widely used in experimental and industrial scenarios that require precise temperature control. In materials testing, it provides constant temperature cooling for calorimeters, reactors, and other equipment. In the electronics industry, it is used to cool lasers, semiconductor manufacturing equipment. In the field of food testing, the operating temperature is maintained for fermenters, viscometers and other instruments. In addition, it is also commonly used in chemical, auto parts testing, and environmental simulation equipment.
Selection considerations
Multiple parameters need to be considered when selecting. The cooling capacity should be determined according to the heat load and environmental conditions of the equipment, and an appropriate margin should be retained. The temperature range needs to meet the experimental or process requirements, including minimum cooling temperatures and temperature control accuracy. The flow rate and pressure of the circulation pump need to match the pipeline resistance and cooling requirements of the external equipment. In terms of material, corrosion-resistant materials such as stainless steel should be selected for parts that come into contact with liquids. Energy efficiency and noise levels can be evaluated according to the requirements of the laboratory environment. Additionally, the equipment should have safety features such as overload protection and liquid level alarm, as well as consider ease of maintenance.