2. Determine the heat transfer coefficient and the linear heat flux in the transverse air flow for a pipe with a diameter of A=30 mm, if its surface temperature is t_(s)= 90^circ C the air temperature is t_(a)=-10^circ C and the wind speed is w=4m/s

To determine the heat transfer coefficient and the linear heat flux in the transverse airflow for a pipe, we can use the Dittus-Boelter equation, which is a commonly used empirical correlation for convective heat transfer. The Dittus-Boelter equation is given by: where:- is the heat transfer coefficient,- is the Reynolds number,- is the Prandtl number,- is the characteristic length (in this case, the diameter of the pipe),- is the diameter of the pipe.First, we need to calculate the Reynolds number ( ) and the Prandtl number ( ).The Reynolds number is given by: where:- is the wind speed,- is the diameter of the pipe,- is the kinematic viscosity of air.The Prandtl number is given by: where:- is the specific heat capacity of air,- is the dynamic viscosity of air,- is the thermal conductivity of air.Now, let's calculate these values:1. Kinematic viscosity of air ( ): 2. Specific heat capacity of air ( ): \( 1005 \, J/(kg \cdot K) \)3. Dynamic viscosity of air ( ): 4. Thermal conductivity of air ( ): \( 0.03 \, W/(m \cdot K) \)Now, we can calculate the Reynolds number and the Prandtl number: Now, we can use the Dittus-Boelter equation to calculate the heat transfer coefficient: Now, we can calculate the linear heat flux ( ): where:- is the surface temperature of the pipe,- is the air temperature. Therefore, the heat transfer coefficient is approximately \( 589.6 \, W/(m^2 \cdot K) \) and the linear heat flux is approximately .