The Determination of Mass Flow in the Vapour-Compression Refrigerator

1935 ◽  
Vol 129 (1) ◽  
pp. 477-505 ◽  
Author(s):  
E. C. Smith
Keyword(s):  
Experimental Determination ◽  
Mass Flow ◽  
The State ◽  
Volumetric Efficiency ◽  
Coefficient Of Performance ◽  
Flow Meter ◽  
Wide Range ◽  
Liquid Portion ◽  
Vapour Compression

The paper describes an experimental determination of the mass flow of refrigerant per minute and refrigerating effect per minute in a vapour-compression refrigerator, when the state of the refrigerant at the exit from the evaporator was varied over a wide range of superheat temperatures and dryness fractions. The usual methods of measuring the flow of liquids in pipes were not suitable for the present work and a special type of flow meter, described in the text, was developed. The results obtained were not as theory would tend to suggest, but were substantially modified by practical conditions, particularly for dryness fractions between 0·97 and 0·87. The volumetric efficiency changed abruptly over this range from a higher to a lower value. The reduction was attributed to the effect of re-evaporation of. the liquid portion of the refrigerant in the compressor during the suction stroke, as it was found that the higher volumetric efficiency was obtained when the refrigerant was superheated throughout most of the delivery stroke, and the lower volumetric efficiency occurred when the state of the refrigerant on entering the compressor resulted in liquid being present in the cylinder at the end of the delivery stroke. The reduction in the volumetric efficiency resulted in a corresponding reduction in the mass flow, the refrigerating effect, and the heat rejected by the condenser per minute, and in the coefficient of performance for dryness fractions ranging between 0·97 and 0·87.

scholarly journals Analysis of energy efficiency of air handling unit with integrated air to air heat exchanger in heating mode

2020 ◽  
Vol 207 ◽  
pp. 01002
Author(s):  
Slav Valchev ◽  
Ivan Mihaylov
Keyword(s):  
Energy Efficiency ◽  
Heat Exchanger ◽  
Experimental Determination ◽  
Mass Flow ◽  
Coefficient Of Performance ◽  
Supply Side ◽  
High Effectiveness ◽  
Air Handling Unit ◽  
Heating Mode

Object of the present study is an experimental determination of energy efficiency parameters of air handling unit with integrated air to air heat exchanger: effectiveness of air to air heat exchanger, coefficient of performance and specific fan power of air handling unit. A daily performance of air handling unit is conducted. Effectiveness of supply side of air to air heat exchanger in range of 42.4 % to 52.5 % is received. Coefficient of performance in range of 1.50 to 2.08 and specific fan power of air handling unit in range of 1.39 kW/(m3/s) to 2.08 kW/(m3/s) are received. It was found experimentally that effectiveness of air to air heat exchanger depends on values of mass flow of supply and the exhaust air. High values of mass flow of the exhaust air responds to high effectiveness of supply side of air to air heat exchanger.

Influence of the amorphous phase and preceding solution processing on the eutectic behaviour in the state diagram of P3HT : PC61BM determined by rapid heat–cool calorimetry

RSC Advances ◽  
2016 ◽  
Vol 6 (95) ◽  
pp. 92981-92988 ◽  
Author(s):  
M. Defour ◽  
N. Van den Brande ◽  
L. Van Lokeren ◽  
G. Van Assche ◽  
W. Maes ◽  
...  
Keyword(s):  
Experimental Determination ◽  
Amorphous Phase ◽  
Organic Photovoltaics ◽  
State Diagram ◽  
The State ◽  
Solution Processing ◽  
State Diagrams

Experimental determination of eutectic state diagrams for organic photovoltaics based on advanced calorimetry highlighting the importance of the amorphous phase.

A Study on Anasysis and Fabrication of an Ice Plant Model

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
J. P. Yadav ◽  
Bharat Raj Singh
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Unit Mass ◽  
Ice Plant ◽  
Plant Model ◽  
Compression Cycle ◽  
Vapour Compression

Refrigeration may be defined as the process of achieving and maintaining a temperature below that of the surroundings, the aim being to freeze ice, cool some product, or space to the required temperature. The basis of modern refrigeration is the ability of liquids to absorb enormous quantities of heat as they boil and evaporate. One of the important applications of refrigeration is in ice plant. Ice plant is used for producing refrigeration effect to freeze potable water in standard cans placed in rectangular tank which is filled by brine. Our project based on simple refrigeration system which uses the vapour compression cycle. The vapour compression cycle comprises four process compression, condensing, and expansion and evaporation process. Our ice plant model contains various parts such as- Compressor, condenser, filter drier, Expansion valve, Evaporator coil, chilling tank and various measuring equipments like digital temperature indicator, pressure gauges, energy meter etc. The conventional ice plant has been studied and a prototype model of an ice plant has been fabricated with above said accessories. The model is analyzed for its cooling capacity assumed per unit mass flow rate of refrigerant. Its COP is also calculated. The model is compared for its coefficient of performance (COP) and cooling capacity by using R-134 a refrigerant with a theoretical COP and cooling capacity obtained using refrigerant R-22. The variations found in COP and cooling capacity are 0.12 and 0.042 TR respectively for unit mass flow rate of the refrigerant.

Free Molecule Flow Through a Vacuum Seal

1970 ◽  
Vol 92 (3) ◽  
pp. 405-410
Author(s):  
H. S. Yu ◽  
E. M. Sparrow
Keyword(s):  
Mass Flow ◽  
Numerical Solutions ◽  
Rarefied Gas ◽  
Coupled System ◽  
Mass Fluxes ◽  
Wide Range ◽  
Flow Through ◽  
Molecule Flow ◽  
Range Of Values

An analysis is made of the rate of the mass flow through a vacuum seal separating two rarefied gas environments. The determination of the mass throughflow characteristics involves the formulation and solution of a coupled system of six integral equations. The formulation is performed using the methods of kinetic theory. Numerical solutions are carried out for a wide range of values of the seal geometrical parameter. Mass flow results evaluated from these solutions are presented graphically. In addition, representative distributions of the mass fluxes at the participating surfaces are given.

scholarly journals COP enhancement of vapour compression refrigeration system using dedicated mechanical subcooling cycle

2020 ◽  
Vol 39 (3) ◽  
pp. 776-784
Author(s):  
T.S. Mogaji ◽  
A. Awolala ◽  
O.Z. Ayodeji ◽  
P.B. Mogaji ◽  
D.E. Philip
Keyword(s):  
System Performance ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Wide Range ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Vapour Compression ◽  
Better Than

This study focused on development of an improved vapour compression refrigeration system (IVCR system). Dedicated mechanical subcooling cycle is employed in attaining the developed IVCR system. The system is composed of two cycles cascade refrigeration system working with R134a. It consists of a rectangular shape with total storage space of 0.582 m3, made of galvanized mild steel and internally insulated with 0.05 m polystyrene foam. Tests under a wide range operating temperature conditions were carried out on the developed IVCR system. Performance evaluation of the system was characterized in terms of cooling capacity and coefficient of performance (COP). Experimental results showed that the COP of the subcooled system improved better than that of the main system from 18.0% to about 33.5% over an evaporating temperature range of -10 to 30oC. It can be concluded that the use of dedicated sub cooling cycle in VCR system is more efficient and suitable for the betterment of thermal system performance. Keywords: Vapour compression Refrigeration system, Coefficient of performance, dedicated subcooled system, Condensation temperature, Evaporation temperature.

scholarly journals Experimental and Numerical Analysis of Multi-Hole Orifice Flow Meter: Investigation of the Relationship between Pressure Drop and Mass Flow Rate

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7281
Author(s):  
Adam Tomaszewski ◽  
Tomasz Przybylinski ◽  
Marcin Lackowski
Keyword(s):  
Numerical Analysis ◽  
Pressure Drop ◽  
Mass Flow ◽  
Flow Coefficient ◽  
Flow Meter ◽  
Contraction Coefficient ◽  
Single Hole ◽  
Wide Range ◽  
Orifice Flow ◽  
Orifice Flow Meter

The paper presents the results of the experimental and numerical analysis of a six-hole orifice flow meter. The experiments were performed on humid air in a 100 mm diameter duct. The aim of this research was to investigate the mass flow and pressure drop dependency in an orifice of a predetermined shape and to compare the results obtained with computational formulas recommended in the ISO 5167-2 standard for a single-hole orifice flow meter. The experiments and calculations were performed on several multi-hole orifice geometries with different contraction coefficient in a wide range of Reynolds numbers. The pressure was probed immediately upstream and downstream of the orifice. The flow coefficient determined for the six-hole orifice flow meter investigated was compared with the flow coefficient of conventional single-hole orifice with the same contraction coefficient. The results from computational formulas for single-hole orifice from ISO 5167 are also included in the paper. During some experiments, an obstacle has been introduced in the duct at variable distance upstream from the orifice. The effect of the thus generated velocity field disturbance on the measured pressure drop was then investigated. Numerical simulation of the flow with the presence of the obstacle was also performed and compared with experimental data.

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