As a kind of on–off valve, gate valves are widely used in various process industries. When compared with other valves, it needs smaller torque during the open and close processes of the valve, and it also results in smaller flow resistance. However, due to the complexity of the sealing device, more components in gate valves are needed, which might lead to high proneness of gate valve failure [
1,
2,
3].
Researches about various valves have been focused in the past years. For instance, Qian et al. [
4,
5] applied Tesla valves in the hydrogen decompression process and investigated the pressure drop and Mach number in multi-stage Tesla valves. Yuan et al. [
6] and Jin et al. [
7] conducted numerical simulations to study the cavitation inside the poppet valve and the globe valve, and the cavitation characteristics and the structural parameters that affected the cavitation were found. Dasgupta et al. [
8] and Zhang et al. [
9] and Qian et al. [
10] focused on the dynamic valve open and close processes of a proportional valve, a pressure relief valve, and a pilot-control globe valve respectively. Furthermore, Jin et al. [
11] and Qian et al. [
12,
13] investigated the structural parameters of a pilot-control angle valve and a micro Tesla valve, Xu et al. [
14] focused on the pulsatile flow of a mechanical heart valve, Chen et al. [
15] investigated the thermal stress of a pressure-reducing valve, and Qian et al. [
16] analyzed the possibility of the noise distribution in perforated plates connecting pressure-relief valve.
Specific to the gate valves, lots of works have also been done focusing on different issues. There are works regarding the flow resistance and the temperature distributions. Solek and Mika [
17] investigated the relationship between the loss coefficient and the Reynolds number for gate valves with ice slurry flow, and their experiments showed that the loss coefficient remained constant in the turbulent regime, but decreased with the increase of the Reynolds number in the laminar regime. Alimonti [
18] and Lin et al. [
19] studied the flow characteristics and resistance characteristics of a gate valve with different openings and different inlet velocities, and it was found that the flow resistance could be gradually stabilized when the opening was larger than 2/8 [
19]. Long and Shurong [
20] numerically investigated the flow and temperature distributions in the stem gate valve while using axisymmetric models, and Hu et al. [
21] performed experiments and numerical simulations to study the temperature and the convection heat transfer coefficient distributions in a gate valve. In the meantime, there are also works regarding structure optimization [
22,
23], the corrosion erosion distributions [
24,
25,
26], and the stress analysis [
27,
28,
29]. Kolesnikov and Tikhonov [
22] focused on the conicity of the output channel of the wedge gate valve and Xu et al. [
23] focused on the seal and piston of a subsea gate valve. Babaev and Kerimov [
24] found that there was fretting corrosion for a parallel slide gate valve. Lin et al. [
25,
26] found that the erosion rate in a gate valve was related to the pipe diameter, the cavity width, and the inlet velocity [
25], while the open degree had little effects but a large Stokes number could increase the difference of erosion distributions for different valve placements [
26]. As for the stress analysis, Liao et al. [
27] found that the fatigue of the inlet valve sleeve resulting from collision stress was the main reason for the valve failure. Zakirnichnaya and Kulsharipov [
28] analyzed the stress-strain of the wedge gate valves while using fluid-structure interaction technology and they found that the safe operation resources value of the wedge is lower than the valve body. Punitharani et al. [
29] applied the finite element analysis (FEA) method to evaluate the residual stresses in a gate valve, and they found that there were large tensile and compressive residual stresses on the circular bead of the gate valve.
Gate valves can be classified into the wedge gate valve, the parallel gate valve, the double disk parallel gate valve, and the double disk wedge gate valve, etc. according to the form of the sealing device. As described above, works regarding parallel gate valves [
18,
19] and wedge gate valves [
22] have been done by researchers. In this paper, a wedge-type double disk parallel gate valve is chosen to be analyzed. The computational fluid dynamics method is used to investigate the flow and loss characteristics under different Reynolds number and different groove depth. Moreover, the structural stress analysis where the valve failure might occur is also done while using a numerical method that is proven by the previous studies [
27,
28,
29,
30,
31]. This work is helpful for the understanding of the flow characteristics of the gate valve and the judgment of the reason for valve failure in the future.