The choice of a thermostatic expansion valve for a CFC12 refrigeration system retrofitted with HFC134a

1993 ◽  
Vol 17 (3) ◽  
pp. 153-164 ◽  
Author(s):  
N. J. Hewitt ◽  
J. T. McMullan ◽  
D. G. Moran ◽  
N. E. Murphy
Keyword(s):  
Refrigeration System ◽  
Expansion Valve

Design and Build of Teaching and Experimental Marine Cold Store

2014 ◽  
Vol 556-562 ◽  
pp. 907-911
Author(s):  
Chang Wei He ◽  
Meng Zhang ◽  
Xiao Ping Jia ◽  
Yuan Liu
Keyword(s):  
Thermal Performance ◽  
System Performance ◽  
Heat Load ◽  
Refrigeration System ◽  
Electrical System ◽  
Technology Application ◽  
Design Scheme ◽  
Expansion Valve ◽  
Cold Store ◽  
Practical Teaching

In the paper, the design scheme of the new cold store is proposed firstly, with the consideration of the latest technology application and the convenience and maneuverability of practical teaching. Then the refrigeration system is designed based on the calculation of the heat load of the cold store. The suited components such as compressor, evaporator, condenser and expansion valve are selected and the electrical system is designed. After that the whole unit is installed and adjusted to make sure that the installation is propitious to improve the system performance and convenient for training. Finally the thermal performance of the new cold store system is tested and compared with the old system test. The result shows that the matching of the new refrigeration system is reasonable and the new cold store is up to the mustard. With the help of training on the cold store, the students will meet the essential requirements of STCW 78/95 convention on application and management of the marine cold store.

scholarly journals Cop Enhancement of Vapour Compression Refrigeration System

2021 ◽  
pp. 1-6
Author(s):  
B Sairamakrishna ◽  
◽  
T Gopala Rao ◽  
N Rama Krishna ◽  
◽  
...  
Keyword(s):  
Tube Diameter ◽  
Coefficient Of Performance ◽  
Refrigeration System ◽  
Expansion Valve ◽  
Compressor Inlet ◽  
Work Input ◽  
Compressor Work ◽  
Vapour Compression ◽  
Design And Testing ◽  
Nozzle Inlet

This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

An Empirical Model for a Variable Speed Refrigeration System

2011 ◽  
Vol 383-390 ◽  
pp. 7563-7568
Author(s):  
Hua Li ◽  
Ji You Fei
Keyword(s):  
Decoupling Control ◽  
Opening Angle ◽  
Model Parameters ◽  
Variable Speed ◽  
Refrigeration System ◽  
Order Model ◽  
Indoor Temperature ◽  
First Order ◽  
Proposed Model ◽  
Expansion Valve

This paper deals with an empirical dynamic model for decoupling control of the variable speed refrigeration system (VSRS). To cope with inherent complexity and nonlinearity in system dynamics, the model parameters are first obtained based on experimental data. In the study, the dynamic characteristics of indoor temperature and superheat are assumed to be first-order model with time delay. While the compressor frequency and opening angle of electronic expansion valve are varying, the indoor temperature and the superheat exhibit interfering characteristics each other in the VSRS. Thus, each decoupling model has been proposed to eliminate such interference. Finally, the experiment and simulation results indicate that the proposed model offers more tractable means for describing the actual VSRS comparing to other models currently available.

scholarly journals Performance Evaluation of a Refrigeration System for Fresh Maize Storage

2020 ◽  
pp. 1-9
Author(s):  
O. O. Caleb ◽  
N. G. Olaiya ◽  
M. A. Akintunde
Keyword(s):  
Freezing Temperature ◽  
Refrigeration System ◽  
Production Engineering ◽  
University Of Technology ◽  
Expansion Valve ◽  
Temperature Ranges ◽  
Ondo State ◽  
Wall Stainless Steel ◽  
System Operating

Aims: In this research project, a refrigeration system that will preserve the quality of fresh maize was developed. Study Design:  Design of refrigeration system. Place and Duration of Study: Department of Industrial and Production Engineering, Federal University of Technology, Akure, Ondo State, Nigeria, between August 2017 and February 2018. Methodology: The designed system consists of a cooling cabinet, compressor, condenser and an evaporator. The cabinet was designed to store up to 15 kg of maize and a compressor of 1/6 hp was used. The equivalent condenser and evaporator were selected with an equivalent expansion valve. R134a was used as the refrigerant. The cabinet walls were fabricated from mild steel (outside wall), stainless steel (inner wall) and glass wool (insulator). Results: The fabricated system stores fresh maize above its freezing temperature of -1ºC. The system operating temperature ranges from -4 to 2.5ºC with a relative humidity of 90 to 95% for eight hours. Conclusion: The fresh maize was stored for ten days without noticeable changes in the physical appearance and taste of the maize.

Sign in / Sign up

Export Citation Format

Share Document