Abstract
An experimental study was carried out to investigate the effects of inlet pressure, sample thickness, initial sample temperature, and temperature sensor location on the surface heat flux, surface temperature, and surface ultrafast cooling rate using stainless steel samples of diameter 27 mm and thickness (mm) 8.5, 13, 17.5, and 22, respectively. Inlet pressure was varied from 0.2 MPa to 1.8 MPa, while sample initial temperature varied from 600°C to 900°C. Beck's sequential function specification method was utilized to estimate surface heat flux and surface temperature. Inlet pressure has a positive effect on surface heat flux (SHF) within a critical value of pressure. Thickness of the sample affects the maximum achieved SHF negatively. Surface heat flux as high as 0.4024 MW/m2 was estimated for a thickness of 8.5 mm. Insulation effects of vapor film become apparent in the sample initial temperature range of 900°C causing reduction in surface heat flux and cooling rate of the sample. A sensor location near to quenched surface is found to be a better choice to visualize the effects of spray parameters on surface heat flux and surface temperature. Cooling rate showed a profound increase for an inlet pressure of 0.8 MPa.
Highlights
Water spray quenching of metals got a lot of attention due to its very high cooling efficiency
Weber number (We) studied 1D spray heat transfer from top surface of the heater so cylindrical surface of the heater was insulated with ceramic tube and bottom surface was insulated with fiber glass insulation
The increase in the mass flow rate is exponential as shown in Figure 3, which suggests the existence of a saturation value of flow rate beyond which it cannot increase even with a corresponding increase in the inlet pressure
Summary
Water spray quenching of metals got a lot of attention due to its very high cooling efficiency. In present study Beck’s function specification method was utilized to investigate the effect of spray parameter on the time-varying boundary surface condition of stainless steel sample during quenching process. In a typical production line of run out table of steel industry, the strips are reheated to a hot rolling temperature close to 900∘C and cooled down to coiling temperature of 600∘C [16] Cooling in this temperature range should develop multiphase microstructures to produce advance high quality steels. Current study focused on effects of inlet spray pressure, thickness of the sample, initial sample temperature, and sensor location on surface heat flux, surface temperature, and cooling rate during ultrafast inverse heat conduction from stainless steel plate utilizing Beck’s sequential function specification method with one interior point temperature history
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
