Heat Loss Formula
Heat Loss Formula
The amount of energy that spontaneously flows from one body to another due to a temperature difference is what we call heat. Objects with uneven temperatures in their thermal system tend towards thermal equilibrium. A hot body transfers heat to a cold body until they are at the same temperature, that is, until they reach thermal equilibrium. Conduction, convection, and radiation are methods of heat loss. The Heat Loss Formula is the reduction in heat present in a room due to heat transfer through walls, roofs, windows and building surfaces. Students can calculate the Heat Loss Formula by multiplying the area value, the temperature difference between the inner and outer surfaces, and the heat loss value of the material. The convective Heat Loss Formula is the percentage of heat lost in the ventilation of hot processes. Total heat loss from an object includes losses caused by radiation, convection, and conduction. No material can completely prevent heat loss, it can only minimize heat loss. A watt is a unit of heat loss. Learners should take the help of Extramarks website for Heat Loss Formula as it is a student-friendly website which is a reliable source of information.
What Is Heat Loss?
Heat loss is the reduction of heat in a space caused by heat transfer through walls, roofs, windows and building surfaces. Calculate heat loss by taking the product of the area value, the temperature difference between the inner and outer surfaces, and the heat loss value of the material. The convective Heat Loss Formula is a heat loss that is particularly relevant when ventilating hot processes.
Heat Loss Formula:
Heat loss is denoted by the symbol q. Its dimension is given by [M1 L2 T-3]. It is directly proportional to the overall heat transfer coefficient, the area of the object, and the temperature difference between the object and the environment. So that formula is the product of the total transmittance, the area of the object, and the temperature difference. That formula is expressed as:
q = (U × A) × Δt
Where,
q is the total Heat Loss Formula in watts. U will be the overall transmission coefficient. A will be the area of the object/building. Δt reflects the temperature difference between indoors and outdoors.
Methods Of Heat Loss
Heat can be described as the amount of energy that naturally flows between two bodies due to a temperature difference. In a thermal system, bodies with different temperatures tend to approach thermal equilibrium. A hotter body transfers heat to a cooler body until the temperatures are equal or until the bodies reach thermal equilibrium. The Heat Loss Formula can be the result of any of these factors: radiation, convection, or even conduction.
1] Heat Conduction
Heat conduction, also called diffusion, occurs within a body or between two bodies in contact. This is the direct kinetic energy exchange of particles across the boundary between two systems. Heat transfer by conduction to achieve thermal equilibrium when an object is at a different temperature than its surroundings or another body.
The heat transfer rate depends on the resistance that exists between the different temperatures of the two surfaces. Thermal resistance (R) is the ability of a material to retard the transfer of heat by conduction through a particular thickness of the material.
Mathematically, thermal resistance (R)=Lk
L insulation thickness
k thermal conductivity
2] Heat Convection
Thermal convection relies on the transfer of mass from one region of space to another. Thermal convection also occurs when the bulk flow of a fluid (gas or liquid) transports heat along with the mass flow within the fluid.
3] Thermal Radiation
Radiation is heat transfer by electromagnetic radiation. B. Sunlight, if the matter does not need to be in the space between objects. To do this, the hotter surface temperature must be above the ambient temperature. This is much higher than typical heat tracing applications.
Solved Examples For Heat Loss Formula
Q.1: Determine the total Heat Loss Formula of a building with an area of 60 m², a heat transfer coefficient of 0.7 and a temperature difference of 25 °C.
Solution: Given
U = 0.7
E=60
= at 25 °C
Substituting these values into the given formula,
q = (U × A) × Δt
q=0.7×60×25
Therefore, q = 1050 watts
Q.2. Determine the total Heat Loss Formula of a building with a calorific value of 4.5 watts, an area of 10 m2, and a ΔT value of 5∘C.
Solution: Given
U = 4.5 watts
A=10㎡
Δt = 5° C
Substitute the value into the given expression,
q = (U × A) × Δt
q = 4.5 x 10 x 5
Hence, q = 225 watts
