Performance Evaluation of Modified Low-Temperature Cascade (MLTC) Type Refrigeration System

2021 ◽  
pp. 2150023
Author(s):  
Mohd Waseem Siddiqui ◽  
Nishith Kumar Das ◽  
R. K. Sahoo
Keyword(s):  
Performance Evaluation ◽  
Low Temperature ◽  
Cooling Tower ◽  
Coefficient Of Performance ◽  
Slight Variation ◽  
Refrigeration System ◽  
Isentropic Compression ◽  
Compression Efficiency ◽  
Normal Water ◽  
Cascade Type

An experimental investigation was carried out to study the performance evaluation of Modified Low-Temperature Cascade (MLTC) system, based on two-stage cascade type refrigeration system using the combination of R404A/R23 refrigerants. This system was developed using chilled water (CHW) in the condenser of high-temperature circuit (HTC) and pre-cooler (PC) in the low-temperature circuit (LTC). Isentropic compression efficiency is computed in this work and used here as an important parameter. Performance of MLTC system was compared with or without the introduction of PC into LTC. System’s coefficient of performance (COP) has also been compared with using CHW, cooling tower water (CTW), normal water (NW) into the HTC condenser. It has also been shown that COPs of the system are significantly affected by slight variation in the LTC and HTC evaporating temperatures. Presented parameters and comparisons are likely to help in developing a low-temperature (LT) refrigeration system with higher efficiency for industrial and other applications.

Optimal Allocation of Heat Transfer Surface of a Two-Stage Refrigeration System

Volume 4 ◽  
2004 ◽  
Author(s):  
M. J. Morales ◽  
S. A. Sherif
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
High Performance ◽  
Optimal Allocation ◽  
Low Cost ◽  
Coefficient Of Performance ◽  
Refrigeration System ◽  
Two Stage ◽  
Isentropic Compression ◽  
Inventory Allocation

The purpose of this study is to investigate how the heat exchanger inventory allocation plays a role in maximizing the thermal performance of a two-stage refrigeration system with two evaporators. First, the system is modeled as a Carnot refrigerator and a particular heat transfer parameter is kept constant as the heat exchanger allocation parameter is allowed to vary. The value of the heat exchanger allocation parameter corresponding to the maximum coefficient of performance (COP) is noted. The results are compared to those of a non-Carnot refrigerator with isentropic and non-isentropic compression. It is found that the Carnot refrigerator can be used to predict the value of the heat exchanger allocation parameter where the maximum COP occurs for a non-Carnot refrigerator. In order to improve the accuracy of that prediction, the predicted value of the heat exchanger allocation parameter has to be inputted into the set of equations used for the non-Carnot refrigerator. This study is useful in designing a low cost, high-performance refrigeration system.

scholarly journals The effect of the chilled water temperature on the performance of an experimental air-cooled chiller

2021 ◽  
Author(s):  
Phan Thi Thu Huong ◽  
Hoang Mai Hong ◽  
Lai Ngoc Anh
Keyword(s):  
Water Temperature ◽  
Coefficient Of Performance ◽  
Condensation Temperature ◽  
Measured Temperature ◽  
Isentropic Compression ◽  
Compression Efficiency ◽  
Evaporation Temperature ◽  
Study Results ◽  
Chilled Water ◽  
Temperature And Pressure

This paper presents the study results on the effect of the chilled water temperature on the coefficient of performance (COP) of an experimental air-cooled chiller. The measuring sensors and instrument were calibrated, and the uncertainty of the measuring temperature and pressure were evaluated. The uncertainty of measured temperature and pressure at 95% confidence level is 0.12 °C and 1.4 kPa, respectively. The isentropic compression efficiency and the COP of the air-cooled chiller operating at a condensation temperature of 48.05 °C and evaporation temperature of 3.17 °C are 63% and 2.69, respectively. The chilled water temperature has a significant influence on evaporation pressure and the COP of the chiller. If the temperature of the air entering the condenser of the chiller is maintained at 35 °C, the COP of the chiller increases from 2.55 to 2.89 when the temperature of the chiller water increases only 4 K, from 8 °C to 12 °C.

scholarly journals THEORETIC-EXPERIMENTAL EVALUATION OF A CASCADE REFRIGERATION SYSTEM FOR LOW TEMPERATURE APPLICATIONS USING THE PAIR R22/R404A

2012 ◽  
Vol 11 (1-2) ◽  
pp. 07
Author(s):  
J. J. Fiori ◽  
C. U. S. Lima ◽  
V. Silveira Jr
Keyword(s):  
Low Temperature ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Refrigeration System ◽  
Evaporation Temperature ◽  
Optimal Value ◽  
Cascade Refrigeration System ◽  
The Difference ◽  
Cascade Refrigeration ◽  
Good Agreement

This paper presents a thermodynamic analysis of a cascade refrigeration system using the refrigerant R22 as the working fluid in the high temperature circuit (HT) and the refrigerant R404a as the working fluid in the low temperature circuit (LT). The present analysis aimed to obtain the condensing temperature of the LT that provides an optimal value for the coefficient of performance (COP) of the cycle. Parameters involved in the analysis included the evaporation temperature, the condensing temperature and the difference between the condensing temperature of the LT (TC_LT) and evaporation temperature of the HT (TE_HT) – ΔTCAS. Simulations were performed using the software EES (Engineering Equation Solver). In addition to the analysis, experimental data obtained from a prototype was compared with the simulated results which showed good agreement. The COP varies with the increase in the intermediate temperature; however this variation does not exceed 1%.

Experimental Investigation of Ejector Refrigeration System With Double Condensers

2018 ◽  
Author(s):  
H. H. Sait ◽  
B. A. Habibullah ◽  
N. Turkman ◽  
H. B. Ma
Keyword(s):  
Experimental Investigation ◽  
High Temperature ◽  
Low Temperature ◽  
Air Conditioning ◽  
Experimental System ◽  
Back Pressure ◽  
Coefficient Of Performance ◽  
Refrigeration System ◽  
Energy Applications ◽  
Waste Energy

This paper presents the results of an experimental investigation of a steam jet refrigerator suitable for renewable or low-medium grade waste energy applications. An experimental system of an ejector refrigeration system was constructed and fabricated. Different parameters of the ejector refrigeration system were investigated, such as the high-temperature evaporator (HTE) temperature, low temperature evaporator (LTE) temperature, and back pressure. The coefficient of performance (COP) of the ejector refrigeration system was determined. In addition, the effects of the operating temperatures on the COP and critical back pressure were investigated. The results are expected to motivate the use of ejector refrigeration systems for air-conditioning.

Sign in / Sign up

Export Citation Format

Share Document