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REFRIGERATION SYSTEM

TITLE:   REFRIGERATION SYSTEM OBJECTIVES ·   To study the refrigeration cycle and measure the coefficient of performance (C.O.P) of refrigerator. ·  T o plot the vapor-compression cycle in a pressure-enthalpy graph. THEORY In the system of air conditioning the vapor compression refrigeration cycle is commonly used. The fluid which works as medium in the vapor compression refrigeration cycle is in vapor state. During evaporation, it absorbs heat from the cold body and this heat is used as its latent heat for converting it from liquid to vapor whereas in Condensing or cooling, it rejects heat to external bodies, thus creating a cooling effect in the working fluid. The Vapor Compression Refrigeration Cycle involves four components: compressor, condenser, expansion valve/ throttle valve and evaporator. It is a compression process, whose aim is to raise the refrigerant pressure as it flows from evaporator. The high-pressure refrigerant flows through a condenser/hea...
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TEMPERATURE MEASUREMENT BENCH

 TITLE:   TEMPERATURE MEASUREMENT BENCH Objectives: ·   To learn the fundamental temperature measurement techniques using the thermocouple and resistance temperature detector, RTD (Pt-100). ·   To compare the accuracy of the various temperature measurement devices. Theory: Temperature is the degree of hotness or coldness of a body or environment (corresponding to its molecular activity). It is measured by means of a thermometer or other instrument having a scale calibrated in units called degrees. A temperature scale is determined by choosing two reference temperatures and dividing the temperature difference between these two points into a certain number of degrees. The two reference temperatures used for most common scales are the melting point of ice and the boiling point of water. The scale we use to measure temperature is "degrees" (°). There are three temperature scales that are used today. i.   The Kelvin (K) scale is used by scientists and for...

THERMAL CONDUCTIVITY OF METAL ROD

TITLE: THERMAL CONDUCTIVITY OF METAL ROD Objectives: ·        To determine the coefficient of thermal conductivity of metal rod. Theory: Thermal conductivity is a fundamental property of materials that describes their ability to conduct heat. Conduction is a process of heat transfer through solids. When a temperature gradient exists in a body, experiment has shown that there is a transfer of heat from the high temperature region. The heat transfer rate per unit area is proportional to the temperature gradient given by: Where, Q= heat transfer rate in watts A = area of heat transfer in m²   𝑑𝑇/dx = temperature gradient in the direction of heat flow in °C/m K= coefficient of thermal conductivity of the material  The negative sign indicates that heat flows in the direction of decreasing temperature. The coefficient of thermal conductivity of a substance is a physical property, which is defined as the ability of a substance to co...

ANGULAR MEASUREMENT USING SINE BAR

TITLE: ANGULAR MEASUREMENT USING SINE BAR OBJECTIVES To understand and get familiar with the use of the sine bar. To use trigonometric relationship to set up exact measurements on a workpiece. To understand and use sine bar, and make it reliable tool. To get familiar with the use of dial indicator. To discuss the sources of errors and discuss methods to minimize them . APPARATUS REQUIRED Sine bar Dial indicator Indicator Stand Set of slip gauges Metal surface plate THEORY Sine Bar A  sine bar  consists of a hardened, precision ground body with two precision ground cylinders fixed at the ends. The distance between the centers of the cylinders is precisely controlled, and the top of the bar is parallel to a line through the centers of the two rollers. The distance between the centers of the rollers is standardized (for ease of later calculations) and forms the hypotenuse of a triangle when in use.  ...

PRECISION MEASUREMENT USING MICROMETER SCREW GAUGE

TITLE: PRECISION MEASUREMENT USING MICROMETER SCREW GAUGE OBJECTIVES 1.               To understand and get familiar with the use of the micrometer screw gauge. 2.               To determine the least count of the micrometer. 3.               To measure the dimensions of slip gauges using the micrometer and calculate the measurement errors by comparing the measured values with standard values. 4.               To analyze the need of micrometer over Vernier caliper. 5.               To discuss the sources of errors and discuss methods to minimize them . APPARATUS REQUIRED                1.    ...