The measurement of turbulence is necessary to quantify the vertical, diapycnal transport of heat, water and substances influencing climate, nutrient supply and marine ecosystems. As specialist instrumentation and ship-time are required to conduct microstructure measurements to quantify turbulence intensity, there is a need for more inexpensive and easy measurement methods. This study demonstrated that the turbulent energy dissipation rate, ε, estimated from fast-response thermistors Fastip Probe model 07 (FP07) with the depth-average of a > 10 m depth interval well agreed with those from current shear probes to a range of 10–11 W/kg (m2s−3) in the two casts of the most accurate and stable free-fall vertical microstructure profiler, VMP6000 in the Oyashio water. This range cannot be measured with velocity shear probes equipped in smaller profilers in which the lower limit of ε > O (10–10) W/kg. These results extend turbulence measurements using the FP07 to 10–11 W/kg. They may be especially useful for turbulence observations in deep oceans where ε is generally weak (< 10–10 W/kg). As FP07 are much less sensitive to instrument vibrations than current shear and may be attached to various observational platforms such as temperature-conductivity-depth (CTD) profilers and floats. The CTD-attached FP07 observations near the VMP6000 profiles demonstrated their capabilities in the ε range of 10–11–10–8 W/kg by data screening using a $${W}_{\mathrm{sd}}>0.1(W-0.3)$$ W sd > 0.1 ( W - 0.3 ) criterion (1 s mean lowering rate $$W$$ W m/s and its standard deviation $${W}_{\mathrm{sd}}$$ W sd ) under rough conditions where the cast-mean $${W}_{\mathrm{sd}}>$$ W sd > 0.07 m/s and the standard deviation of $${W}_{\mathrm{sd}}$$ W sd in each cast $$\sigma$$ σ >0.05 m/s.

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The mechanism of gas-water two-phase percolation was previously characterized based on percolation experiments. However, the changes in the gas-water interface and the volume fraction of the two phases in the process of gas-water percolation in porous media cannot be accurately described by experiments. This paper uses core casting thin sections and AutoCAD software to establish a digital core. Based on the idea of level set, a two-dimensional gas-water seepage model in microscopic pores is established. The finite element numerical simulation software is used to solve the model to describe the gas. The changes of the water two-phase interface are visually displayed. At the same time, Darcy’s law is used to compare the relative permeability curve obtained from the gas-water two-phase seepage experiment with the relative permeability curve obtained from the gas-water two-phase seepage finite element simulation. The results show that the gas-water two-phase seepage experiment and the gas-water two-phase seepage finite element numerical simulation have basically the same characterization of the seepage ability of porous media. There is obvious fingering phenomenon in the process of gas flooding, and the gas preferentially passes through the large pore throat. The smaller the pore throat, the greater the velocity of gas passing through the pore throat. The gas-water two-phase interface change described by the numerical simulation of the gas-water two-phase flow based on the digital core is more reliable.