A liquid food is being heated in a tubular heat exchanger. The inside pipe wall temperature is 110°C. The internal diameter of the pipe is 30 mm.The product fl ows at 0.5 kg/s. If the initial temperature of the product is 7°C, compute the convective heat-transfer coeffi cient. The thermal properties of the product are the following: specifi c heat 3.7 kJ/(kg°C), thermal conductivity 0.6 W/(m °C), product viscosity 500 10 6 Pa s, density 1000 kg/m 2, product viscosity at 110°C 410 10 6 Pa s.