Big name:
Heat, physical terms and coal industry are often used to express the calorific value of coal. Can be used in food to explain the energy contained. Not for academic purposes, the standard unit is joule.
Calorie is the abbreviation of Calorie, transliterated from English Calorie. It is defined as the heat required to raise 1 gram of water at 1 atmospheric pressure. Calories are energy units, which are widely used in nutrition measurement and fitness manuals.
Calorie is a common term in the coal industry. 1 kg coal with heat of 1000 calories is equivalent to 0. 143 kg standard coal. For example, 7000 kcal coal means that the calorific value of coal is 7000 kcal/kg, which is equivalent to engineering. A unit of heat. 1 calorie = 1000 calories, which are mostly used in nutrition measurement and fitness manuals.
For example, if the temperature of 1kg pure water increases or decreases 1 degree Celsius, the heat absorbed or released is 1 calorie. A large calorie is a thousand calories. Used to evaluate the quality of fuel, one kilogram of fuel can raise X kilograms of water by 1 degree Celsius, which means that the calorific value of this fuel is X calories. The usual unit of heat in China is 20℃, that is, the heat required for 1 g pure water to rise from 19.5℃ to 20.5℃.
Heat calculation formula:
The formula for calculating heat is a formula for calculating heat, that is, q = g c (TG-th). When the heating system provides the same heat Q to the heat users, the temperature difference between supply and return water Δ δt = TG-th is directly proportional to the circulating water quantity g, that is, if the temperature difference between supply and return water in the system is large, the circulating water quantity will be small and the power consumption of the pump will be greatly reduced. From the following example, we can see the relationship between temperature difference and power consumption.
Formula use:
The secondary pipe network of direct supply system or indirect supply system also has the problem of too small operating temperature difference. Generally, the indoor heating system of users is designed according to the temperature difference of supply and return water of 25℃, but the actual operating temperature difference is below 20℃, and some even only have about 10℃. Therefore, there is a problem that a large amount of electric energy is wasted. Secondary pipe network and indoor heating system also have great energy-saving potential.