Under what circumstances can the calculated volume flow rate under standard liquid conditions be used?
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Recently, while studying flow meters and the calculation of flow rates for gases and liquids, I found it easy to understand concepts such as gas operating conditions, standard condition volume flow rate, gas mass flow rate, liquid volume, and liquid mass flow rate. However, I have doubts regarding the standard condition volume flow rate for liquids, and I could not find any relevant calculation formulas or conversion formulas.
The so-called standard conditions refer to the parameters adopted as general rules: atmospheric pressure and temperature. Without this benchmark, for example, since atmospheric temperature changes constantly, the volume of air delivered by a compressor is specified based on standard conditions. Initially, 20°C was used as the reference point, but with the adoption of the SI system, 0°C is now used for calculations. With this base value, it is possible to determine the amount of atmosphere at any temperature. Look up “standard conditions” online. For reference.
For liquids, the density of gases is greatly affected by changes in temperature and pressure. Therefore, in the calculations related to gaseous media in daily work, temperature and pressure compensation for standard operating conditions is necessary.
Standard conditions are relative to operating conditions. The volumetric flow rate and mass flow rate of compressible fluids vary under different conditions, as the volume and density of such fluids change with pressure and temperature; consequently, their volumetric flow rate and mass flow rate also change. To obtain the volumetric flow rate and mass flow rate under standard conditions, it is necessary to make pressure and temperature corrections to the volumetric flow rate and mass flow rate under the actual operating conditions. A liquid is an incompressible fluid; its volume and density are not affected by temperature or pressure, so the flow rate under operating conditions is the same as the flow rate under standard conditions.
It is generally assumed that liquids are incompressible under normal conditions; the volume under operating conditions is the same as the volume at standard conditions, so no conversion is necessary. If so-called standard conditions must be used, it might be more practical to specify the temperature.
The density of some liquids changes at different temperatures. If we want to convert the flow rate under actual operating conditions to standard conditions (at a specified temperature, such as 20°C), what algorithm should be used?
If flow rate is measured in volume, it is independent of temperature. If flow rate is measured in mass, then mass is equal to volume multiplied by the density at the specified temperature. Are you majoring in the humanities?