Using Evaporative Cooling Methods for Improving Performance of an Air-cooled Condenser

Abstract

In areas with very hot weather conditions (50 to 60℃), the temperature and pressure of the airconditioning condenser are increased considerably. This causes a decrease in the cooling capacity of the cycle and also causes an increase in the power consumption due to increased pressure ratio. In this work, an experimental and theoretical investigation has been done to improve the evaporator outlet fluid temperature through enhancing condenser performance. For this purpose, several modifications on the refrigeration system have been developed and tested to solve this hot weather problem. The air-side modifications include adding Spray Water above condenser (SW), wet Pad before condenser (Pad), and water Vapor Nozzle in the condenser air flow (VN). The refrigerant-side modification includes adding a pair of Heat Exchangers (HE) for exchanging heat between condenser exit and evaporator exit by using water-antifreeze mixture as a working fluid. A Water-Refrigerant(W-R) evaporator has been designed, manufactured, and compared with original Air-Refrigerant(A-R) evaporator performance. All air and refrigerant-side modifications have been investigated using both types of evaporators. The results indicate that the (SW) modification for enhancing condenser performance is the best method for COP improvement. The COP of (SW) system is found to increase at rate of (44.5 %) and (102.1%) as compared to system without modifications for (A-R) and (W-R) evaporators respectively. The outlet cooling temperature from evaporator has been found to reduce by about (30.3%) for (A-R) evaporator and (23.6%) for (W-R) evaporator. However, (HE+Pad) modification has been found as the best method for improving air side Nusselt number of condenser with an increase of about (4.7) times that of system without modifications. Ten new Nusselt number correlations have been predicted for each type of modifications under investigation by using both Engineering Equation Solver (EES) software and the experimental data. Cost-Benefit analysis in terms of life cycle cost, net present value, cost-benefit ratio, and payback period have been conducted. From the analysis, it can be concluded that using (SW) system will save a significant amount of energy with a payback period of less than five years.

Key implications on food storage in cold chain by energy management perspectives

“…Some of those; the air-side modifications include adding spray water above condenser, wet pad before condenser, and water vapor nozzle in the condenser air flow. Studies on adding spray water above condenser, one of these solutions, have shown that it is an important tool for increasing cooling capacity and also reducing power consumption, especially in hot climates (Vrachopoulos et al, 2007;Alhamdo et al, 2015).…”

Analisis Pengaruh Waktu Dan Tekanan Terhadap Demineralisasi Air Buangan Ac Dengan Metode Reverse Osmosis

“…Dewasa ini, penggunaan AC semakin meningkat seiring dengan bertambahnya suhu lingkungan akibat pemanasan global. Manusia terus mengembangkan teknologi untuk menyejukkan udara yang lebih efisien karena seiring dengan berkembangnya teknologi, manusia mulai menyadari bahwa efek dari penggunaan alat pendingin ruangan dapat menyebabkan konsumsi energi tinggi (Alhamdo, 2015). AC yang digunakan menghasilkan air buangan yang berasal dari proses pengembunan (evaporasi) dan proses kondensasi (Sarbu, 2014).…”

Optimum and Sustainable Cooling Technology Selection for Different Climatic Conditions

“…The average investment cost of evaporative coolers is around USD 2000 for producing a cooling effect equivalent of kW. A maximum of 10 • C reduction in the condenser temperature reduced the specific power consumption by 0.085 kW/kW of cooling [34]. The effect of evaporative coolers is maximum in dry ambient conditions producing cooling up to 10 • C and moderate under humid conditions, producing a cooling of 5 • C. A 10 • C temperature reduction produces a 40% increase in COP and a 5% temperature reduction produces a 20% improvement in COP.…”