temperature

There are three commonly used temperature units (temperature scales): Celsius temperature, Fahrenheit temperature, and absolute temperature.

Celsius temperature (t, ℃): The temperature we often use. The temperature measured using a Celsius thermometer.

Fahrenheit temperature (F, ℉): commonly used temperature in European and American countries.

Temperature conversion:

F (℉)=9/5 * t (℃)+32 (calculate Fahrenheit temperature based on known Celsius temperature)

T (℃)=[F (℉) -32] * 5/9 (calculate Celsius temperature based on known Fahrenheit temperature)

Absolute temperature scale (T, K): Generally used in theoretical calculations. Conversion between absolute temperature scale and Celsius temperature: T (K)=t (℃)+273 (calculate absolute temperature based on known Celsius temperature)

pressure

In refrigeration, pressure is the vertical force acting on a unit area, that is, pressure, usually measured using a pressure gauge or pressure gauge. The commonly used units of pressure are:

Mpa (megapascals);

Kpa (kilopascals);

Bar;

Kgf/cm2 (square centimeter kilogram force);

Atm (standard atmospheric pressure);

MmHg (millimeters of mercury).

Conversion relationship:

1Mpa=10bar=1000Kpa =7500.6 mmHg = 10.197 kgf/cm2

1atm=760mmHg=1.01326bar =0.101326Mpa

Generally used in engineering:

1bar = 0.1Mpa ≈1 kgf/cm2 ≈ 1atm = 760 mmHg

Absolute pressure: The pressure directly acting on the surface of a container or object.

Gauge pressure: The pressure measured by the pressure gauge is the gauge pressure.

Vacuum degree (H): When the gauge pressure is negative, its absolute value is taken and expressed as vacuum degree.

Refrigeration/Heat

The amount of heat transferred by a refrigerator from a low-temperature object to a high-temperature object per unit time. Heating capacity refers to the amount of heat absorbed by an air conditioner (heat pump type) from the outside and transmitted indoors per unit of time.

COP refrigeration capacity/compressor electromechanical power. The performance coefficient of the winter heat pump cycle and the energy efficiency ratio of the summer heat pump are expressed using COP (Energy Efficiency Ratio).

EER refrigeration capacity/total electrical power of the air conditioning system (the higher the EER value, the more heat is absorbed by evaporation in the air conditioning or the less electricity is consumed by the compressor). During summer cooling, the ratio of cooling capacity (W or Btu/h) to input power (W) is defined as the energy efficiency ratio (EER) of the heat pump.