EXERIMENTAL CALCULATIONS :

Diameter of Orifice, mm (d₁) =34

Diameter of pipe, mm (d₂) =68

Coefficient of discharge Cd= 0.6
Density of manometer fluid (water),w (kg/m^₃)  =1000

Density of air, (kg/m^₃)  =1.126

g = 9.81 m/s²

Flow rate = 70 ltr/hr

 

S. No.	T1	T2	T3	T4	T5	T6	R1(cm)	R2(cm)	QW (LPH)
1	19	17.5	38.6	36	44.5	30.5	5.6	9.5	3.9
2	19.5	18.1	35.4	34.4	43.7	28.3	3	12.1	9.1
3	20	18.7	35.1	34	44.1	28	0.2	14.1	13.9

 

CALCULATIONS :

 =34.54 m

a₁ =Cross Section area of Orifice, m^₂= 907.46 *10^-6  m   

a₂ = Cross Section area of pipe, m² =3629.84*10-6 m

  = 0.01463 m³/s

 nbsp;= 0.0165 kg/s

 =0.01944 kg/s

=1.178

From Enthalpy table, the enthalpy of entering air at a wet bulb temp i.e.17.5 ⁰C is h₁= 15.274 Btu/lb of air

                    =15.274 + 1.178(44.5-30.5)

                    =31.766 Btu/lb of air

 

T,0F	hwi	hai
T=T2 =63.5	hw =   --------	ha  = h1  =15.274	--------
T=T2 +0.1(T1-T2)=63.77	hw =32.12	ha  = h1+0.1(L/G)(T5-T6) =18.25	13.87
T=T2 +0.4(T1-T2)=64.56	hw =33.12	ha  = h1+0.4(L/G)(T5-T6) =27.19	5.93
T=T2 -0.4(T1-T2)=65.12	hw =33.62	ha  = h2-0.4(L/G)(T5-T6)= 19.84	13.78
T=T2 -0.1(T1-T2)=65.93	hw =34.11	ha  = h2-0.1(L/G)(T5-T6) = 28.78	5.33
T=T1  =66.2	hw =34.32	ha  = h2 = 31.76	2.56

 

Cooling range = T₅-T₆  = 14⁰C

Temperature approach =T₂-T₆ = -13⁰C

                    =

                     = 0.501

Now tower characteristics

             =1.7535

 On doing the similar calculations for different values of (L/G),we get the complete calculation table.From there we draw a graph between tower characteristics and (L/G).