Keywords

44.1 Introduction

The main objective of this project is to reduce the size of the condenser and enhance the heat transfer rate. The Condenser is a device used to exchange the heat absorbed to ambient. It rejects heat to an external cooling medium (air or water) [1, 2] be those procedure of evacuating high temperature from an encased space, or from A substance, furthermore moving it will a spot the place it cam wood a chance to be excluded in high face area, low FPI & optimum refrigerant flow through condenser coil and air flow over the condenser coil are the key for effective condenser performance [3, 4].

In the present study, the condenser coil circuit is optimized so that the refrigerant flow through the condenser flows via two tubes parallels and the heat exchange between the refrigerant and the external surface occurs very quickly [5,6,7] (Fig. 44.1).

Fig. 44.1
figure 1

Detailed explanation of condenser with phase change

Full size image

44.2 Experimental Setup of Condenser Optimization

The issues that mainly affect the heat transfer rate in a required convection type condenser.

44.2.1 Air-Cooled Condenser Selection

Air-cooled condenser might be a common convection sort alternately to constrained convection sort. On practically as a relatable point, we utilize air-cooled condenser [8, 9]. In front of measuring a condenser, cautious assessment of the necessities for a particular establishment will be fundamental. The assessment ought to include, attention from claiming starting cost, operating cost, administration and aggregation, furthermore the kind about load [10,11,12]. A condenser that is excessively little camwood make unreasonable What’s more make operating issues in easier encompassing states a under-size condenser camwood make working issues in higher encompassing states [13]. It is, therefore, paramount to think about those taking after factors in front of measuring a condenser:

  • Terrible heat dismissal.

  • Encompassing temperature.

  • Consolidating temperature.

  • Temperature distinction (TD).

  • Wind stream.

Condenser ability is the capacity of the essential high-temperature exchange equation [14].

$$Qc = U \times A \times LMTD$$

here

$$\begin{aligned} {\text{Qc }} & = {\text{Condenser capacity in Cal}}/{\text{h}} \\ & \quad \left( {{\text{Ref}}. {\text{effect }} + {\text{Heat of Comp }} + {\text{Motor winding heat}}} \right) \\ \end{aligned}$$
$$\begin{aligned} U & = {\text{Overall}}\,{\text{heat}}\,{\text{transfer}}\,{\text{coefficient}}\,{\text{K}}\,{\text{Cal}}/{\text{m}}^{2} {\text{h}}.\, \\ & \quad CA = {\text{Effective}}\,{\text{surface}}\,\,{\text{area}}\,{\text{in}}\,{\text{m}}^{2} \\ \end{aligned}$$
$$\begin{aligned} {\text{LMTD }} & = {\text{Log mean temperature difference between the }} \\ & \quad {\text{condensing refrigerant and the}}\,{\text{condensing medium in}}\, ^\circ {\text{C }} \\ \end{aligned}$$

Face area = Air quantity/Air velocity

The greatest speed happens between those tubes since the tubes block An and only those streams acceptably [15]. If B is those dividing among tubes in the face and c may be the tube dividing among rows, also d may be those tube breadths. The Reynolds and Nusselt number are defined as follows for this case:

$$\text{Re} \, = \,\left( {\rho \, \times \, do \, \times \, U\infty } \right)/\mu$$

The Grimson’s correlation is as follows:

where the constants C and n are dependent upon Reynolds number (Tables 44.1 and 44.2).

Table 44.1 Constant for Grimson’s equation
Full size table
Table 44.2 Observation for condenser
Full size table

Enthalpy values taken from P-h chart

H1 = 400 kJ/kg H4 = 270 kJ/kg H2 = 430 kJ/kg H5 = 245 kJ/kg H3 = 420 kJ/kg H6 = 245 kJ/kg

Refrigerant Effect = H1 − H6

= 155 kJ/kg

Heat Rejection Capacity (HRC) = (Refrigeration capacity * power of compressor) * FOS

= ((1.6) + (678/1000)) × 1.05 = 2.392 KW

Overall heat transfer coefficient

1/Uo = (At/Ai) × (1/hi condensation) + 1/ho Uo = 47.46 W/m2 K

LMTD condensation = 7.61 °C

44.2.2 CAD Modeling

See Figs. 44.2, 44.3, 44.4, 44.5 and 44.6.

Fig. 44.2
figure 2

Existing design with 12 tube single circuit

Full size image
Fig. 44.3
figure 3

New design with 11 tube

Full size image
Fig. 44.4
figure 4

Condenser coil with fins

Full size image
Fig. 44.5
figure 5

Condenser coil without fins

Full size image
Fig. 44.6
figure 6

Physical model of the design

Full size image

44.2.3 ANALYSIS-Structural Analysis

Boundary Conditions:

Inlet: Temperature: 85 [°C]

Outlet: Mass flow rate = 0.0137(kg/s) Ref. Pressure: 14.7 [PSI] Assumptions:

Steady state single phase analysis (Figs. 44.7 and 44.8, Table 44.3).

Fig. 44.7
figure 7

11 *4 row condenser velocity streamlines

Full size image
Fig. 44.8
figure 8

Temperature contour

Full size image
Table 44.3 Velocity and temperature
Full size table

44.3 Results and Discussion

By comparing the two models the outlet temperature of the new design is better. By optimizing the circuit design from one circuit to two circuit the heat transfer rate of the condenser is improved by 6% though the height of the condenser is decreased by 9% by reducing one row of the tube. The capacity increased from 3.17 to 3.37 KW. With this achievement, the higher capacity of the compressor can be used for the same refrigeration system and can be used in very compact-sized refrigeration units. The above data is calculated from the LUVATA Thest. Condenser design Software and the images of the same are shown below (Figs. 44.9 and 44.10).

Fig. 44.9
figure 9

Input for 11 tubes condenser

Full size image
Fig. 44.10
figure 10

Output for 11 tubes condenser

Full size image

44.4 Conclusion

By optimizing the circuit designs from one circuit to two circuits the heat transfer rate of the condenser is improved by 6% though the size of the condenser is decreased by 9% by reducing one row of the tube. The capacity increased from 3.17 to 3.37 KW. With this achievement, the higher capacity of the compressor can be used for the same refrigeration system and can be used in very compact-sized refrigeration units. With this new design, the cost of the unit can be reduced by about 5–6%. In conclusion, by optimizing the circuit design the performance of the condenser can be improved.