A double pipe heat exchanger is constructed from a steel with an inner tube having inner diameter of $26,44$ mm and outer diameter of $33,40$ mm$.$The length of pipe is $10$m$.$it is desired to use this heat exchanger in the heating of $1500$ kg$/$h milk from $20\backslash$deg C to $85\backslash$deg C $($density :$1030$ kg$/$m$3,$ Cp$=4$ kj$/$kg $\backslash$deg C$).$ In the given temperature range $,$ average viscosity of milk is $1,4\backslash$times $10^-3$ Pa$.$s and the thermal conductivity is $0,56$ W$/$m$.$K$.$ The heating medium is $2200$ kg hot water per hour which has a temperature of $95\backslash$deg C $.$ Milk will be passed from the inner pipe. The fouling coefficient for milk is $4,76\backslash$times $10^-4$ m$2.$K$/$W$.$ a$)$ Find the outlet temperature of water for this process

b$)$Is this double pipe heat exchanger is satisfactory for yourrt requirement based on calculations

c$)$What type of heat transfer mechanism occurs in that system $,$ give yourrt reasings by explaining the mechanism briefly and drawing the thermal resistance diagram.