Thermodynamics Lab manual for students.pptx

Manual

1. Lab-1:To measure rate of heat conduction Objectives:  To investigate Fourier’s law of linear conduction  To investigate the temperature profile and heat transfer in radial direction of a cylinder To investigate the effect of change in cross-sectional area on the temperature profile

2. Theory Heat transfer is defined as the transmission of energy from one region to another as a result of temperature gradient takes places by the following three modes: 1. Conduction 2. Convection 3. Radiation Conduction is the transfer of heat from one part of a substance to another part of the same substance or from one substance to another in physical contact with it, without appreciable displacement of molecules forming the substance. Fourier‘s law of heat conduction states that the rate of flow of heat through a simple homogeneous solid is directly proportional to the area of the section at right angles to the direction of heat flow, to the change of temperature with respect to the length of the path of the heat flow.

3. Mathematically I t can be represented by the equation: Q α A.dt /dx Where, Q = heat flow through a body per unit time, W A = surface area of the heat flow (perpendicular to the direction of the flow), m2 dt = temperature difference of the faces of the block of thickness dx through which heat flow, oC or K dx = thickness of the body in the direction of flow, m

4. Conduction of heat along a simple bar Observation: Specimen material: Brass Thermal conductivity of the specimen from tables: Diameter of specimen: 25 mm Length of specimen: 30 mm Distance between temperature probes: 10 mm

5. Conduction of heat along a simple bar

6. Conduction of heat in radial direction: Observation sheet Specimen material: Brass Thermal conductivity of the specimen from tables: Outer diameter of specimen: 110 mm Inner diameter of specimen: 8 mm Length of specimen: 3 mm Distance between temperature probes: 10 mm

7. Conduction of heat in radial direction: